:root{--green:#176b52;--deep:#173c31;--ink:#19362e;--muted:#667a72;--line:#d9e5e0;--pale:#eef7f3;--cream:#fbfaf4;--danger:#9b3d38}
*{box-sizing:border-box}
body{margin:0;background:linear-gradient(180deg,#f8fbf9,#fbfaf4 38%);color:var(--ink);font-family:Inter,"Noto Sans SC","Microsoft YaHei",Arial,sans-serif;line-height:1.7}
.bd-header{position:sticky;top:0;z-index:10;display:flex;align-items:center;justify-content:space-between;gap:22px;padding:13px clamp(18px,4vw,54px);background:rgba(255,255,255,.96);border-bottom:1px solid var(--line);backdrop-filter:blur(12px)}
.bd-brand{display:flex;align-items:center;gap:12px;color:var(--ink);text-decoration:none}
.bd-brand img{width:46px;height:46px;border-radius:13px}
.bd-brand span{display:flex;flex-direction:column}
.bd-brand b{font-size:17px}
.bd-brand small{color:var(--muted);font-size:12px}
.bd-header nav{display:flex;gap:18px}
.bd-header nav a{color:var(--deep);font-weight:750;text-decoration:none}
.bd-wrap{width:min(1160px,calc(100% - 32px));margin:0 auto;padding:54px 0 80px}
.bd-hero{padding:clamp(28px,5vw,58px);border:1px solid rgba(23,107,82,.18);border-radius:30px;background:radial-gradient(circle at 92% 12%,rgba(244,202,101,.26),transparent 28%),linear-gradient(135deg,#fff,#eaf6f0);box-shadow:0 22px 60px rgba(23,60,49,.10)}
.bd-kicker{color:var(--green);font-size:12px;font-weight:900;letter-spacing:.1em}
.bd-hero h1,.bd-detail h1{margin:8px 0 12px;font:700 clamp(34px,5vw,58px)/1.12 Georgia,"Noto Serif SC",serif}
.bd-hero>p{max-width:850px;font-size:18px}
.bd-note{color:var(--muted)!important;font-size:14px!important}
.bd-stat-row{display:flex;flex-wrap:wrap;gap:12px;margin:25px 0}
.bd-stat-row span{display:flex;align-items:baseline;gap:7px;padding:10px 15px;border-radius:999px;background:#fff;border:1px solid var(--line);color:var(--muted)}
.bd-stat-row b{color:var(--green);font-size:22px}
.bd-search{margin:34px 0 44px}
.bd-search label{display:block;margin-bottom:7px;font-weight:800}
.bd-search div{display:flex;gap:10px}
.bd-search input{flex:1;min-width:0;padding:14px 17px;border:1px solid var(--line);border-radius:13px;background:#fff;font:inherit}
.bd-search button{padding:0 25px;border:0;border-radius:13px;background:var(--green);color:#fff;font-weight:850}
.bd-section{margin:38px 0}
.bd-section>h2{font:700 28px/1.25 Georgia,"Noto Serif SC",serif}
.bd-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:15px}
.bd-card{position:relative;min-height:170px;padding:23px;border:1px solid var(--line);border-radius:20px;background:#fff;color:var(--ink);text-decoration:none;box-shadow:0 8px 26px rgba(23,60,49,.06);transition:.2s}
.bd-card:hover{transform:translateY(-3px);border-color:#98c7b6;box-shadow:0 16px 36px rgba(23,60,49,.11)}
.bd-card>span{color:#84a99b;font:700 15px Georgia,serif}
.bd-card h3{margin:9px 0 4px;font-size:19px;line-height:1.35}
.bd-card p{margin:0 0 16px;color:var(--muted)}
.bd-card small{position:absolute;left:23px;bottom:18px;color:var(--green);font-weight:800}
.bd-empty{padding:20px;border-radius:16px;background:#fff;border:1px dashed var(--line);color:var(--muted)}
.bd-breadcrumb{display:flex;justify-content:space-between;gap:20px;margin-bottom:26px;color:var(--muted)}
.bd-breadcrumb a{color:var(--green);font-weight:800;text-decoration:none}
.bd-detail{overflow:hidden;border:1px solid var(--line);border-radius:28px;background:#fff;box-shadow:0 18px 50px rgba(23,60,49,.08)}
.bd-detail>header{display:flex;align-items:center;gap:22px;padding:32px clamp(25px,4vw,48px);background:linear-gradient(135deg,#e8f5ef,#fff)}
.bd-detail>header h1{font-size:clamp(32px,4vw,48px)}
.bd-detail>header p{margin:0;color:var(--muted);font-size:20px}
.bd-number{display:grid;place-items:center;flex:0 0 70px;height:70px;border-radius:20px;background:var(--green);color:#fff;font:700 27px Georgia,serif}
.bd-learning-grid{display:grid;grid-template-columns:1fr 1fr;gap:1px;background:var(--line)}
.bd-learning-grid section{padding:26px 30px;background:#fff}
.bd-learning-grid .bd-wide{grid-column:1/-1}
.bd-learning-grid h2{margin:0 0 8px;font-size:15px;color:var(--green)}
.bd-learning-grid p{margin:0;white-space:pre-line}
.bd-learning-grid .bd-danger{background:#fff7f5}
.bd-danger h2{color:var(--danger)}
.bd-tags{display:flex;flex-wrap:wrap;gap:9px}
.bd-tags span{padding:7px 11px;border-radius:999px;background:var(--pale);color:var(--deep);font-weight:750}
.bd-questions{margin-top:34px;padding:30px;border:1px solid var(--line);border-radius:25px;background:#fff}
.bd-question-head{display:flex;align-items:center;justify-content:space-between;gap:20px}
.bd-question-head h2{margin:4px 0 18px}
.bd-question-head>strong{font:700 48px Georgia,serif;color:#b1c9bf}
.bd-question-list{display:grid;gap:10px}
.bd-question-list>a{display:grid;grid-template-columns:45px 1fr auto;gap:14px;align-items:center;padding:16px;border:1px solid var(--line);border-radius:14px;color:var(--ink);text-decoration:none}
.bd-question-list>a:hover{border-color:#86baa7;background:#f7fbf9}
.bd-question-list>a>span{display:grid;place-items:center;width:38px;height:38px;border-radius:10px;background:var(--pale);color:var(--green);font-weight:900}
.bd-question-list b{display:block;line-height:1.45}
.bd-question-list small{display:block;margin-top:4px;color:var(--muted)}
.bd-question-list i{font-style:normal;color:var(--green);font-size:24px}
.bd-pager{display:flex;justify-content:space-between;margin-top:28px}
.bd-pager a{padding:11px 16px;border:1px solid var(--line);border-radius:12px;background:#fff;color:var(--green);font-weight:800;text-decoration:none}
.bd-question-page{max-width:1000px}
.bd-full-question{padding:clamp(24px,5vw,50px);border:1px solid var(--line);border-radius:28px;background:#fff;box-shadow:0 16px 46px rgba(23,60,49,.08)}
.bd-full-question h1{font:700 clamp(25px,3.5vw,40px)/1.4 Georgia,"Noto Serif SC",serif}
.bd-options{display:grid;gap:11px;margin:28px 0}
.bd-options>div{display:grid;grid-template-columns:50px 1fr;align-items:center;border:1px solid var(--line);border-radius:15px;overflow:hidden}
.bd-options b{display:grid;place-items:center;align-self:stretch;min-height:58px;background:#f4f8f6}
.bd-options span{padding:14px 17px}
.bd-options .correct{border-color:#65a78e;background:#f2faf6}
.bd-options .correct b{background:var(--green);color:#fff}
.bd-answer{margin-top:30px;padding-top:24px;border-top:1px solid var(--line)}
.bd-answer h2{color:var(--green)}
.bd-answer h3{margin-top:28px}
.bd-answer p{white-space:normal}
@media(max-width:820px){.bd-grid{grid-template-columns:1fr 1fr}
.bd-header{align-items:flex-start}
.bd-header nav{gap:10px;font-size:13px}
.bd-learning-grid{grid-template-columns:1fr}
.bd-learning-grid .bd-wide{grid-column:auto}
}
@media(max-width:560px){.bd-wrap{width:min(100% - 22px,1160px);padding-top:28px}
.bd-header{position:static;padding:11px}
.bd-brand img{width:38px;height:38px}
.bd-brand b{font-size:14px}
.bd-header nav a:first-child{display:none}
.bd-grid{grid-template-columns:1fr}
.bd-hero{padding:25px 20px;border-radius:22px}
.bd-hero h1{font-size:36px}
.bd-search div{align-items:stretch}
.bd-search button{padding:0 17px}
.bd-detail>header{align-items:flex-start;padding:24px 20px}
.bd-number{flex-basis:54px;height:54px;border-radius:15px;font-size:21px}
.bd-learning-grid section,.bd-questions{padding:22px 18px}
.bd-question-list>a{grid-template-columns:38px 1fr}
.bd-question-list i{display:none}
.bd-breadcrumb{font-size:13px}
.bd-question-head>strong{font-size:36px}
}
.bd-bank-tabs{display:flex;flex-wrap:wrap;gap:10px;margin:0 0 18px}
.bd-bank-tabs a{display:inline-flex;align-items:center;gap:8px;padding:10px 16px;border:1px solid var(--line);border-radius:999px;background:#fff;color:var(--deep);font-weight:850;text-decoration:none}
.bd-bank-tabs a:hover{border-color:#86baa7;background:#f7fbf9}
.bd-bank-tabs a.active{border-color:var(--green);background:var(--green);color:#fff}
.bd-bank-tabs b{display:inline-grid;place-items:center;min-width:25px;height:25px;padding:0 7px;border-radius:999px;background:rgba(23,107,82,.10);font-size:12px}
.bd-bank-tabs a.active b{background:rgba(255,255,255,.2)}
.bd-count-only{display:flex;align-items:baseline;justify-content:center;gap:10px;padding:24px;border-radius:16px;background:var(--pale);color:var(--muted)}
.bd-count-only b{color:var(--green);font:700 42px Georgia,serif}
.bd-count-only span{font-weight:800}

/* 54-condition visual study: scoped so the existing question page keeps its layout. */
body.bd-study-site{--bd-ink:#143d33;--bd-green:#155a49;--bd-muted:#6d8075;--bd-gold:#b88b3b;--bd-line:#dbe1cf;--bd-paper:#fbfaf2;margin:0;color:var(--bd-ink);background:radial-gradient(ellipse at 2% 8%,#dfe9dd 0,transparent 32%),radial-gradient(ellipse at 96% 24%,#f2e9cd 0,transparent 30%),linear-gradient(155deg,#f4f6eb 0%,#fdfbf3 48%,#edf2e6 100%);font-family:Inter,"PingFang SC","Microsoft YaHei",Arial,sans-serif;font-size:15px;line-height:1.65;overflow-x:clip;min-height:100vh}
.bd-study-site:before{content:"";position:fixed;inset:0;z-index:-1;pointer-events:none;background:radial-gradient(circle at 8% 88%,#a7bda52a 0,transparent 32%),radial-gradient(circle at 90% 5%,#fffdf5e6 0,transparent 34%)}
.bd-study-site *, .bd-study-site *:before,.bd-study-site *:after{box-sizing:border-box}
.bd-study-site [hidden]{display:none!important}
.bd-study-site a{color:inherit}
.bd-study-site button,.bd-study-site input{font:inherit}
.bd-study-site button,.bd-study-site a{-webkit-tap-highlight-color:transparent}
.bd-study-site button{cursor:pointer}
.bd-study-site button:disabled{opacity:.3;cursor:default}
.bd-study-site a:focus-visible,.bd-study-site button:focus-visible,.bd-study-site input:focus-visible,.bd-study-site summary:focus-visible,.bd-study-site [tabindex]:focus-visible{outline:2px solid var(--bd-gold);outline-offset:4px}
.bd-study-site .bd-icon{width:28px;height:28px;display:inline-block;flex-shrink:0;vertical-align:middle}
.bd-symbols{position:absolute;width:0;height:0;overflow:hidden}
.bd-sr-only{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.bd-skip{position:fixed;top:-100px;left:16px;z-index:200;padding:10px 20px;background:#fff;color:var(--bd-green);border:2px solid var(--bd-gold)}
.bd-skip:focus{top:12px}
.bd-study-site [data-needs-js]{display:none}
.bd-study-site.bd-enhanced [data-needs-js]{display:inline-flex}
.bd-topbar{position:sticky;top:0;z-index:30;height:80px;display:flex;justify-content:space-between;align-items:center;gap:20px;padding:0 max(24px,calc((100vw - 1320px)/2));background:linear-gradient(110deg,#fafbf3ee,#fffdf7ee);border-bottom:1px solid #cfd9c9;box-shadow:0 3px 14px #254d3410,inset 0 1px #fff;backdrop-filter:blur(16px)}
.bd-wordmark{display:flex;align-items:center;gap:12px;text-decoration:none;line-height:1.1}
.bd-wordmark>span:last-child{display:flex;flex-direction:column;gap:6px}
.bd-wordmark b{font:700 24px Georgia,serif;letter-spacing:.05em}
.bd-wordmark small{font-size:10px;letter-spacing:.13em;color:var(--bd-muted)}
.bd-wordmark-dot{color:var(--bd-gold)}
.bd-brand-seal{position:relative;display:grid;place-items:center;width:45px;height:45px;border:1px solid #bda571;border-radius:50%;color:var(--bd-green);font:italic 30px Georgia,serif;box-shadow:inset 0 0 0 4px #f7f5e8,0 0 0 4px #d9dfce55}
.bd-brand-seal:after{content:"";position:absolute;inset:4px;border:1px solid #bda57166;border-radius:50%;pointer-events:none}
.bd-brand-seal>span{position:absolute;right:3px;bottom:5px;background:#fbfaf1;font:9px "Songti SC",serif;color:var(--bd-gold)}
.bd-topnav{display:flex;gap:22px;align-items:center;font-size:13px;font-weight:600;white-space:nowrap}
.bd-topnav a{text-decoration:none}
.bd-language{font-size:12px;letter-spacing:.05em;padding:8px 2px}
.bd-account{display:flex;align-items:center;gap:7px;border:1px solid #d2ddcb;border-radius:30px;padding:8px 15px;background:linear-gradient(#fffef7,#f0f3e7);box-shadow:inset 0 1px #fff,0 3px 10px #23463109}
.bd-status-dot{width:5px;height:5px;border-radius:50%;background:#578d70;box-shadow:0 0 0 3px #92b09a22}
.bd-main{max-width:1320px;width:calc(100% - 64px);margin:0 auto;padding:37px 0 64px}
.bd-paper{position:relative;isolation:isolate;border:1px solid #d1dbc5;border-radius:22px;background:radial-gradient(ellipse at 20% 0%,#ffffffd9 0,transparent 72%),linear-gradient(140deg,#fffef8,#f7f7ec);box-shadow:0 1px 2px #274b3020,0 12px 30px #274b300b,0 30px 70px #274b3008,inset 0 1px #fff}
.bd-paper:after{content:"";position:absolute;inset:5px;z-index:-1;border:1px solid #d6d7bc80;border-radius:17px;pointer-events:none;box-shadow:inset 0 1px 0 #fff}
.bd-directory-hero{text-align:center;padding:35px 30px 26px;overflow:hidden;outline:1px solid #fff9;outline-offset:5px;box-shadow:0 1px 2px #274b3020,0 16px 40px #274b3010,0 35px 85px #274b300c,inset 0 1px #fff}
.bd-eyebrow{font-size:9px;line-height:1.5;letter-spacing:.18em;font-weight:700;color:#8d8e69}
.bd-directory-hero>.bd-eyebrow{position:relative;display:flex;align-items:center;justify-content:center;gap:13px;color:#8e825b}
.bd-directory-hero>.bd-eyebrow>span{display:block;width:32px;height:1px;background:linear-gradient(90deg,transparent,#b79b60)}
.bd-directory-hero>.bd-eyebrow>span:last-child{transform:rotate(180deg)}
.bd-directory-hero h1{position:relative;margin:12px 0 2px;font:700 clamp(28px,3.6vw,47px)/1.3 "Songti SC","STSong","Noto Serif SC",Georgia,serif;letter-spacing:.055em;color:#103e34}
.bd-hero-subtitle{position:relative;margin:3px 0 0;font-size:19px;letter-spacing:.13em;font-weight:500;color:#5b8777}
.bd-hero-description{position:relative;margin:12px 0 0;font-size:13px;color:#788878;letter-spacing:.025em}
.bd-hero-facts{position:relative;display:flex;justify-content:center;align-items:center;gap:22px;margin:22px 0 18px}
.bd-hero-facts>span{display:flex;align-items:baseline;gap:6px;color:#788574;font-size:11px}
.bd-hero-facts b{font:600 25px Georgia,serif;color:var(--bd-green)}
.bd-hero-facts>i{height:19px;width:1px;background:#c5cdb18c;transform:rotate(15deg)}
.bd-hero-orbit{position:absolute;width:340px;height:340px;right:-130px;top:-146px;border:1px solid #b2c6a840;border-radius:50%;background:radial-gradient(circle,#ddedda40,transparent 70%);pointer-events:none}
.bd-hero-orbit>span,.bd-hero-orbit>i{position:absolute;inset:17px;border:1px solid #c8b68333;border-radius:50%}
.bd-hero-orbit>i{inset:37px;border-style:dashed;border-color:#a3bfa22b}
.bd-hero-orbit>.bd-icon{position:absolute;left:75px;bottom:62px;width:90px;height:90px;color:#a0b89e52;transform:rotate(-18deg)}
.bd-progress-line{position:relative;border-top:1px solid #d4dcc478;display:flex;align-items:center;justify-content:center;gap:14px;padding-top:15px;font-size:10px;color:#8a927d}
.bd-progress-line b{font-weight:600;color:var(--bd-green);margin-left:7px}
.bd-progress-line small{font-size:9px;color:#9b9f8c}
.bd-progress-line progress{appearance:none;width:130px;height:4px;overflow:hidden;border:0;border-radius:20px;background:#e3e8d8}
.bd-progress-line progress::-webkit-progress-bar{background:#e3e8d8}
.bd-progress-line progress::-webkit-progress-value{border-radius:20px;background:#6f977c}
.bd-progress-line progress::-moz-progress-bar{border-radius:20px;background:#6f977c}
.bd-directory-tools{display:flex;align-items:center;justify-content:space-between;gap:16px;margin:27px 0 14px}
.bd-search-form{display:flex;align-items:center;gap:10px;max-width:530px;flex:1;padding:6px 6px 6px 14px;border:1px solid #d3ddc8;border-radius:12px;background:linear-gradient(135deg,#fffef9,#f7f8ee);box-shadow:0 3px 9px #2c4f3005,inset 0 1px 2px #fff}
.bd-search-form>.bd-icon{width:18px;height:18px;color:#8aa38b}
.bd-search-form input{width:100%;min-width:0;border:0;background:transparent;padding:5px 0;color:var(--bd-ink);font-size:13px;outline:none}
.bd-search-form input::placeholder{color:#9ba692}
.bd-search-form button{border:1px solid #2b6951;border-radius:8px;padding:6px 18px;color:#fffdf1;font-size:12px;white-space:nowrap;background:linear-gradient(150deg,#286953,#104b3d);box-shadow:inset 0 1px #ffffff28,0 2px 4px #254b351a}
.bd-result-label{font-size:11px;color:#8b977f;white-space:nowrap}
.bd-result-label b{font:500 15px Georgia,serif;color:var(--bd-green)}
.bd-system-nav{position:sticky;top:80px;z-index:20;display:flex;align-items:center;gap:8px;padding:10px 0 13px;overflow-x:auto;scrollbar-width:none;background:linear-gradient(180deg,#f4f6edfa 65%,#f4f6ed00);backdrop-filter:blur(8px);scroll-padding:12px}
.bd-system-nav::-webkit-scrollbar{display:none}
.bd-system-nav>a{flex:0 0 auto;padding:7px 14px;border:1px solid #d6dfca;border-radius:30px;text-decoration:none;font-size:11px;background:linear-gradient(140deg,#fffef8,#f2f5e9);color:#6d826b;box-shadow:inset 0 1px #fff,0 2px 5px #25482b05;transition:background .2s,color .2s}
.bd-system-nav>a.is-active{border-color:#285b45;background:linear-gradient(140deg,#28664e,#144c3b);color:#fffde9;box-shadow:0 3px 8px #1e50301a,inset 0 1px #ffffff20}
.bd-system{scroll-margin-top:155px;margin:28px 0 39px}
.bd-system-heading{display:flex;align-items:end;gap:20px;justify-content:space-between;padding:0 2px 14px;border-bottom:1px solid #d3dcc4;margin-bottom:18px;position:relative}
.bd-system-heading:after{content:"";position:absolute;bottom:-2px;left:0;height:3px;width:37px;border-radius:4px;background:#a98f4e}
.bd-system-heading>div{display:flex;align-items:baseline;gap:12px;flex-wrap:wrap}
.bd-system-heading small{font-size:9px;letter-spacing:.16em;color:#a19b7c;font-weight:700}
.bd-system-heading h2{margin:0;font:600 22px/1.3 "Songti SC","Noto Serif SC",Georgia,serif;letter-spacing:.05em}
.bd-system-heading p{margin:0;color:#8f9b84;font:italic 12px Georgia,serif}
.bd-system-heading>span{font-size:10px;color:#9b9e86;white-space:nowrap}
.bd-condition-grid{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:17px}
.bd-condition-card{position:relative;display:flex;flex-direction:column;min-width:0;min-height:202px;border:1px solid #d6dec7;border-radius:15px;padding:17px 17px 13px;background:radial-gradient(ellipse at 15% 0,#fffefbe6,transparent 65%),linear-gradient(143deg,#fffef5,#f1f4e8);color:#143d33;text-decoration:none;box-shadow:inset 0 1px #fff,inset 0 -1px 0 #ffffff96,0 2px 3px #3c59370a,0 9px 17px #3c593707;transition:transform .23s,border-color .23s,box-shadow .23s}
.bd-condition-card:before{content:"";position:absolute;inset:4px;border:1px solid #ffffffb5;border-radius:11px;pointer-events:none}
.bd-condition-card:after{content:"";position:absolute;inset:-4px;border:1px solid #b8c8a720;border-radius:19px;pointer-events:none;opacity:.4;transition:opacity .23s}
.bd-card-top{display:flex;justify-content:space-between;align-items:start;gap:10px;margin-bottom:9px}
.bd-organ-ring{position:relative;display:grid;place-items:center;width:55px;height:55px;border:1px solid #a1b8a443;border-right-color:transparent;border-bottom-color:#b6c8af55;border-radius:50%;color:#287a61;background:radial-gradient(circle,#e5edda4d,transparent 72%);box-shadow:inset 0 0 0 4px #fffffa70}
.bd-organ-ring:after{content:"";position:absolute;right:0;top:6px;width:4px;height:4px;background:#819d725c;border-radius:50%;box-shadow:0 0 0 3px #fffef66b}
.bd-organ-ring>.bd-icon{width:44px;height:44px}
.bd-gold .bd-organ-ring,.bd-lesson-organ.bd-gold{color:#b9923e}
.bd-gold .bd-organ-ring{border-color:#c0a4674d;border-right-color:transparent;background:radial-gradient(circle,#e9d9ab35,transparent 72%)}
.bd-card-number{font:500 12px Georgia,serif;letter-spacing:.04em;color:#a7ae91;padding-top:3px}
.bd-condition-card h3{margin:2px 0 5px;font:600 18px/1.16 Georgia,"Times New Roman",serif;overflow-wrap:anywhere;text-wrap:pretty}
.bd-condition-card p{margin:0 0 14px;font-size:13px;line-height:1.45;font-weight:600;color:#41654f;overflow-wrap:anywhere}
.bd-card-bottom{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:auto;padding-top:7px;border-top:1px solid #dce3ce85}
.bd-card-state{font-size:9px;letter-spacing:.03em;color:#97a38a;font-weight:400}
.bd-card-direction{display:grid;place-items:center;width:23px;height:23px;border:1px solid #d6decb;border-radius:50%;color:#60846b;background:#fffff33b}
.bd-card-direction>.bd-icon{width:15px;height:15px}
.bd-condition-card.is-learned .bd-card-state{color:#2d8060}
.bd-condition-card.is-learned .bd-card-state:before{content:"✓ ";font-weight:700}
.bd-empty-state{text-align:center;padding:40px 20px;border:1px dashed #ccd6bd;border-radius:15px;color:#7e9175;background:#fffdf580}
.bd-empty-state>.bd-icon{display:block;width:32px;height:32px;margin:0 auto 14px;color:#9eae8e}
.bd-not-found{padding:14px 20px;border:1px solid #dcccb3;background:#fff6e6;color:#88703f;border-radius:12px;margin-top:0}
.bd-directory-footnote{max-width:750px;margin:40px auto 0;text-align:center;color:#9ba38e;font-size:10px;line-height:1.8}
.bd-site-footer{border-top:1px solid #cdd8c4;text-align:center;padding:30px 20px 35px;background:linear-gradient(#f0f3e6aa,#e8efdfaa)}
.bd-site-footer>span{font:700 22px Georgia,serif;letter-spacing:.1em;color:#41664e}
.bd-site-footer p{margin:7px 0;color:#829279;font-size:11px;letter-spacing:.07em}
.bd-site-footer small{font-size:8px;letter-spacing:.18em;color:#9fa58d}
.bd-trail{display:flex;align-items:center;gap:18px;font-size:12px;color:#8d9c80;margin:0 0 22px}
.bd-trail a{font-weight:600;color:#426f55;text-decoration:none}
.bd-trail>span{padding-left:18px;border-left:1px solid #d0dac2}
.bd-trail>small{margin-left:auto;color:#9c9f84;font-family:Georgia,serif}
.bd-lesson-heading{display:flex;align-items:center;gap:23px;padding:25px 30px;margin-bottom:20px}
.bd-lesson-organ{flex:0 0 82px;width:82px;height:82px;display:grid;place-items:center;border:1px solid #b3c5aa87;border-radius:50%;color:#387a5a;box-shadow:0 0 0 5px #e3e9d640,inset 0 0 0 5px #ffffff80}
.bd-lesson-organ>.bd-icon{width:62px;height:62px}
.bd-lesson-heading>div{min-width:0}
.bd-lesson-heading h1{margin:3px 0 2px;font:600 clamp(25px,3vw,36px)/1.4 "Songti SC","Noto Serif SC",Georgia,serif;letter-spacing:.04em;overflow-wrap:anywhere}
.bd-lesson-heading p{margin:0;font:500 clamp(18px,2vw,25px)/1.25 Georgia,serif;color:#6e8d76;overflow-wrap:anywhere}
.bd-complete-button{align-items:center;justify-content:center;gap:6px;margin-left:auto;flex:0 0 auto;padding:9px 14px;border:1px solid #cbd9bd;border-radius:25px;background:linear-gradient(#fffef8,#edf2e3);color:#6a8e69;box-shadow:inset 0 1px #fff;font-size:11px!important;white-space:nowrap}
.bd-complete-button>.bd-icon{width:18px;height:18px}
.bd-complete-button[aria-pressed=true]{background:#e1ecda;border-color:#91b18a;color:#2d6e4a}
.bd-lesson-tabs{display:flex;gap:24px;align-items:center;border-bottom:1px solid #d0dbc1;margin:24px 0 22px;padding:0 2px;font-size:13px}
.bd-lesson-tabs>a{padding:8px 0 13px;text-decoration:none;color:#829276;position:relative;white-space:nowrap}
.bd-lesson-tabs>a.is-active{color:#265d44;font-weight:700}
.bd-lesson-tabs>a.is-active:after{content:"";position:absolute;height:2px;bottom:-1px;left:0;right:0;background:#a08b4a}
.bd-lesson-tabs span{padding:1px 5px;border:1px solid #d4dec6;border-radius:5px;font-size:10px;margin-left:5px}
.bd-lesson-layout{display:grid;grid-template-columns:minmax(0,1fr) 350px;align-items:start;gap:24px}
.bd-reader{min-width:0;overflow:hidden;padding:18px;scroll-margin-top:105px}
.bd-reader-heading{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:0 3px 15px}
.bd-reader-heading h2{margin:4px 0 0;font-size:16px;font-weight:600;line-height:1.5}
.bd-fullscreen{display:flex;align-items:center;gap:5px;text-decoration:none;font-size:11px;color:#71836a!important;white-space:nowrap;padding:7px 9px;border:1px solid #d7dfc9;border-radius:8px;background:#ffffff70}
.bd-fullscreen>.bd-icon{width:17px;height:17px}
.bd-slide-track{display:flex;overflow-x:auto;overflow-y:hidden;scroll-snap-type:x mandatory;scrollbar-width:none;overscroll-behavior-x:contain;border:1px solid #d4dcc5;border-radius:12px;height:min(74svh,850px);min-height:360px;background:radial-gradient(ellipse at 25% 20%,#e9eee3,#e0e6d7);box-shadow:inset 0 2px 10px #244b2f0d;scroll-behavior:smooth}
.bd-slide-track::-webkit-scrollbar{display:none}
.bd-study-slide{position:relative;flex:0 0 100%;min-width:0;scroll-snap-align:center;scroll-snap-stop:always;height:100%;margin:0;display:flex;align-items:stretch}
.bd-study-slide>a{display:flex;align-items:center;justify-content:center;min-width:0;min-height:0;width:100%;padding:11px}
.bd-study-slide img{width:100%;height:100%;max-width:100%;max-height:100%;object-fit:contain;filter:drop-shadow(0 3px 6px #1a35291a);user-select:none;-webkit-user-drag:none}
.bd-study-slide figcaption{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}
.bd-reader-controls{display:flex;align-items:center;justify-content:center;gap:25px;min-height:76px;padding:13px 0 10px}
.bd-reader-controls>div{text-align:center;min-width:180px;font:500 18px Georgia,serif}
.bd-reader-controls>div>span{color:#a2ad95;font-size:13px}
.bd-reader-controls small{display:block;font:10px/1.5 Inter,"PingFang SC","Microsoft YaHei",Arial,sans-serif;color:#819174;margin-top:4px}
.bd-arrow{display:grid;place-items:center;align-items:center;justify-content:center;width:34px;height:34px;border:1px solid #cedabf;border-radius:50%;background:linear-gradient(#fffef7,#edf1e1);color:#598363;box-shadow:inset 0 1px #fff,0 2px 4px #193c2708}
.bd-arrow>.bd-icon{width:20px;height:20px}
.bd-arrow-left>.bd-icon{transform:rotate(180deg)}
.bd-thumbnails{display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:9px;padding:5px 2px}
.bd-thumbnail{position:relative;display:block;aspect-ratio:1/.99;min-width:0;padding:3px;border:1px solid #d0d8c2;border-radius:8px;background:#e8eddf;overflow:hidden;box-shadow:inset 0 1px #fff;text-decoration:none;transition:border-color .18s,box-shadow .18s}
.bd-thumbnail img{display:block;width:100%;height:100%;object-fit:contain;object-position:center;opacity:.62}
.bd-thumbnail>span{position:absolute;bottom:3px;right:3px;min-width:18px;text-align:center;border-radius:4px;padding:0 3px;background:#f5f7e9db;color:#617e5c;font:9px/16px Georgia,serif;border:1px solid #cfd9be}
.bd-thumbnail.is-active{border-color:#977f40;box-shadow:0 0 0 2px #ba9e5966,0 3px 8px #24492f15;background:#faf8ec}
.bd-thumbnail.is-active img{opacity:1}
.bd-thumbnail.is-active>span{background:#346b4f;border-color:#346b4f;color:#fffbe9}
.bd-reader-hint{margin:11px 0 0;text-align:center;color:#9ba38a;font-size:9px;letter-spacing:.025em}
.bd-study-notes{display:grid;gap:17px;scroll-margin-top:105px;min-width:0}
.bd-study-notes>.bd-paper{padding:24px 24px 21px}
.bd-study-notes h2{margin:5px 0 14px;font:600 22px/1.3 "Songti SC","Noto Serif SC",Georgia,serif;letter-spacing:.04em}
.bd-study-notes h3{font-size:11px;letter-spacing:.02em;color:#5d815f;margin:17px 0 7px}
.bd-study-notes p{margin:0;font-size:12px;line-height:1.9;color:#718469;overflow-wrap:anywhere}
.bd-study-notes .bd-pronunciation{font:400 19px/1.6 Georgia,"Times New Roman",serif;color:#2e6950}
.bd-note-rule{height:1px;margin:17px 0;background:linear-gradient(90deg,#c7d1b5,transparent)}
.bd-study-notes details{border-top:1px solid #d6dfc8;padding:13px 0 0;margin-top:15px}
.bd-study-notes summary{font-size:11px;font-weight:600;color:#557a56;cursor:pointer;list-style:none;padding-right:17px;position:relative}
.bd-study-notes summary::-webkit-details-marker{display:none}
.bd-study-notes summary:after{content:"+";position:absolute;right:0;top:-2px;color:#9a9e7d;font:18px Georgia,serif}
.bd-study-notes details[open]>summary:after{content:"−"}
.bd-study-notes details[open]>p{padding-top:10px}
.bd-study-notes details small{display:block;font-size:9px;line-height:1.8;color:#a0a38c;margin-top:10px}
.bd-study-notes .bd-mechanism-text{padding:13px 14px;border-left:2px solid #baa164;border-radius:0 8px 8px 0;background:linear-gradient(100deg,#ecefdcaa,#f4f6e77a);color:#376b4e;font-size:13px;line-height:1.8}
.bd-study-notes .bd-red-flag summary{color:#9c6b53}
.bd-study-notes .bd-red-flag p{color:#98765e}
.bd-practice-section{margin-top:27px;padding:27px;scroll-margin-top:105px}
.bd-practice-section>header{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:15px}
.bd-practice-section h2{margin:5px 0 0;font:600 24px/1.4 "Songti SC","Noto Serif SC",Georgia,serif}
.bd-practice-count{font:500 38px Georgia,serif;color:#acb99a}
.bd-practice-section>p{font-size:12px;color:#7e9074;margin:15px 0}
.bd-study-site .bd-bank-tabs a{font-size:12px;padding:7px 12px}
.bd-study-site .bd-question-list>a{background:#fffef780;border-color:#d5dec8;border-radius:10px;padding:13px;font-size:12px;grid-template-columns:35px 1fr auto;gap:12px}
.bd-study-site .bd-question-list>a>span{width:30px;height:30px;font-size:11px;background:#e8efdf;color:#65815a}
.bd-study-site .bd-question-list small{font-size:10px;color:#99a389}
.bd-lesson-pager{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-top:28px}
.bd-lesson-pager>a{display:flex;flex-direction:column;align-items:start;padding:16px 19px;border:1px solid #d2dcc3;border-radius:13px;background:linear-gradient(140deg,#fffdf6cc,#f1f4e5aa);text-decoration:none;box-shadow:inset 0 1px #fff,0 4px 12px #224b2a07;min-width:0}
.bd-lesson-pager>a:last-child{align-items:end;text-align:right}
.bd-lesson-pager small{font-size:10px;color:#9a9f84}
.bd-lesson-pager b{font-size:13px;margin-top:4px;font-weight:500;color:#507653;overflow-wrap:anywhere}
.bd-access-panel{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;min-height:390px;padding:48px 30px;margin-top:24px}
.bd-access-icon{display:grid;place-items:center;width:70px;height:70px;border:1px solid #c6b57c85;border-radius:50%;color:#9c8b52;background:radial-gradient(circle,#efe5c347,#fffef360);box-shadow:0 0 0 6px #dcdab02b,inset 0 0 0 5px #fffff670;margin:0 auto 22px}
.bd-access-icon>.bd-icon{width:31px;height:31px}
.bd-access-panel h2,.bd-access-dialog h2{font:600 28px/1.4 "Songti SC","Noto Serif SC",Georgia,serif;margin:9px 0 15px;color:#315d42;letter-spacing:.02em}
.bd-access-panel>p,.bd-access-dialog>p{max-width:510px;font-size:13px;line-height:1.9;color:#89957b;margin:0 auto 23px}
.bd-access-actions{display:flex;justify-content:center;align-items:center;flex-wrap:wrap;gap:10px}
.bd-button-primary,.bd-button-secondary{display:inline-flex;align-items:center;justify-content:center;text-decoration:none;padding:11px 22px;border:1px solid #285a41;border-radius:10px;font-size:12px;font-weight:600;line-height:1.5;min-height:42px}
.bd-study-site .bd-button-primary{background:linear-gradient(145deg,#2a694e,#144632);box-shadow:inset 0 1px #ffffff30,0 3px 7px #28482c15;color:#fffce8}
.bd-study-site .bd-button-secondary{background:linear-gradient(#fffef5,#f3f3e3);border-color:#d0d8bd;color:#778569;box-shadow:inset 0 1px #fff}
.bd-access-back{display:inline-block;margin-top:20px;color:#a3a48b!important;font-size:11px;text-decoration:none}
.bd-access-dialog{width:min(480px,calc(100% - 32px));max-height:calc(100svh - 40px);overflow-y:auto;border:1px solid #c5d0b4;border-radius:23px;background:radial-gradient(ellipse at 15% 0%,#fffefb,#f6f6e8 80%);padding:38px 30px 25px;color:var(--bd-ink);text-align:center;box-shadow:0 30px 120px #06231e44,inset 0 0 0 5px #fefcf2,inset 0 0 0 6px #d8dac0}
.bd-access-dialog::backdrop,.bd-viewer::backdrop{background:#0c3027a1;backdrop-filter:blur(7px)}
.bd-access-dialog>.bd-eyebrow{display:block}
.bd-access-dialog .bd-gate-condition{font-size:11px;color:#aaa284;padding:9px 12px;background:#eceddc77;border-radius:8px;margin:0 auto 17px;overflow-wrap:anywhere}
.bd-access-dialog h2{font-size:25px}
.bd-dialog-close{position:absolute;top:12px;right:13px;border:0;background:transparent;color:#9aa182;font-size:24px!important;line-height:1;padding:5px 9px}
.bd-gate-dismiss{display:block;border:0;background:transparent;color:#a2a68d;margin:21px auto 0;font-size:10px!important;padding:5px}
.bd-viewer{position:fixed;inset:0;width:100%;max-width:none;height:100%;max-height:none;margin:0;border:0;padding:0;background:#0c2b24;color:#ebf0df;overflow:hidden}
.bd-viewer[open]{display:flex;flex-direction:column}
.bd-viewer-toolbar{display:flex;flex:0 0 auto;align-items:center;justify-content:space-between;gap:15px;padding:12px 21px;background:#10382f;border-bottom:1px solid #9cad872d}
.bd-viewer-toolbar>div:first-child{display:flex;align-items:center;gap:15px;min-width:0}
.bd-viewer-toolbar b{font-size:13px;font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.bd-viewer-toolbar [data-viewer-counter]{font:12px Georgia,serif;color:#adc1a6;white-space:nowrap}
.bd-viewer-tools{display:flex;gap:7px;align-items:center}
.bd-viewer-tools button{border:1px solid #869c703d;border-radius:7px;background:#e5edd70a;color:#d0dabe;font-size:15px;min-width:34px;height:33px;padding:0 8px}
.bd-viewer-tools [data-zoom=fit]{font-size:11px}
.bd-viewer-tools [data-viewer-close]{font-size:25px;border-color:transparent;margin-left:7px}
.bd-viewer-stage{flex:1;min-height:0;overflow:auto;display:grid;place-items:center;padding:12px;overscroll-behavior:contain;touch-action:pan-x pan-y pinch-zoom}
.bd-viewer-stage img{display:block;max-width:100%;max-height:100%;width:auto;height:auto;object-fit:contain;user-select:none;-webkit-user-drag:none}
.bd-viewer-stage.is-zoomed{display:block;text-align:center}
.bd-viewer-stage.is-zoomed img{display:block;max-width:none;max-height:none;height:auto;margin:0 auto}
.bd-viewer-stage.zoom-150 img{width:150%}
.bd-viewer-stage.zoom-200 img{width:200%}
.bd-viewer-stage.zoom-300 img{width:300%}
.bd-viewer-bottom{flex:0 0 auto;display:flex;justify-content:space-between;align-items:center;gap:18px;padding:10px 21px max(11px,env(safe-area-inset-bottom));border-top:1px solid #9cad872d;background:#10382f}
.bd-viewer-bottom button{border:1px solid #9cad8740;background:#c9d7b50b;border-radius:8px;padding:8px 13px;color:#d2dec4;font-size:11px;white-space:nowrap}
.bd-viewer-bottom>span{font-size:11px;color:#92ac91;text-align:center}
.bd-study-site.bd-modal-open{overflow:hidden}
.bd-toast{position:fixed;left:50%;bottom:24px;transform:translate(-50%,20px);max-width:calc(100% - 40px);padding:10px 20px;border:1px solid #76957340;border-radius:25px;background:#234f3dec;color:#f7f5e3;box-shadow:0 5px 20px #132f2030;font-size:12px;opacity:0;pointer-events:none;z-index:150;transition:opacity .2s,transform .2s;text-align:center}
.bd-toast.is-visible{opacity:1;transform:translate(-50%,0)}
@media(hover:hover){.bd-condition-card:hover{transform:translateY(-4px);border-color:#b9c6a4;box-shadow:inset 0 1px #fff,0 3px 5px #2d4b2b10,0 16px 24px #2d4b2b12,0 30px 48px #2d4b2b08}.bd-condition-card:hover:after{opacity:1}.bd-condition-card:hover .bd-card-direction{border-color:#8da97d;background:#e7edda}.bd-thumbnail:hover{border-color:#a49a66}.bd-topnav>a:hover{color:#b3934e}}
@media(min-width:1500px){.bd-main{max-width:1400px}.bd-topbar{padding-inline:max(24px,calc((100vw - 1400px)/2))}.bd-condition-grid{grid-template-columns:repeat(6,minmax(0,1fr))}}
@media(max-width:1100px){.bd-condition-grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.bd-lesson-layout{grid-template-columns:minmax(0,1fr) 310px;gap:17px}.bd-study-notes>.bd-paper{padding:22px 20px}.bd-lesson-heading{padding:25px}.bd-main{width:calc(100% - 48px)}}
@media(max-width:850px){.bd-condition-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.bd-lesson-layout{grid-template-columns:1fr}.bd-study-notes{grid-template-columns:1fr 1fr}.bd-study-notes>.bd-clinical-note{grid-column:1/-1}.bd-lesson-heading{gap:18px}.bd-lesson-organ{width:68px;height:68px;flex-basis:68px}.bd-lesson-organ>.bd-icon{width:51px;height:51px}.bd-lesson-heading h1{font-size:29px}.bd-complete-button{padding:8px 10px}.bd-slide-track{height:min(75svh,850px)}.bd-system-heading p{display:none}.bd-main{padding-top:27px}}
@media(max-width:600px){body.bd-study-site{font-size:14px;background:radial-gradient(ellipse at 0% 0%,#dee8d955,transparent 40%),radial-gradient(ellipse at 100% 35%,#efe6ca66,transparent 40%),linear-gradient(155deg,#f5f6ec,#fcfbf3 45%,#edf2e4)}.bd-topbar{height:66px;padding:0 16px;gap:12px}.bd-wordmark{gap:8px}.bd-brand-seal{width:35px;height:35px;font-size:23px;box-shadow:inset 0 0 0 3px #f7f5e8,0 0 0 3px #d9dfce40}.bd-brand-seal>span{font-size:7px;right:1px;bottom:3px}.bd-wordmark b{font-size:20px}.bd-wordmark small{font-size:8px;letter-spacing:.08em}.bd-wordmark>span:last-child{gap:4px}.bd-topnav{gap:13px;font-size:11px}.bd-topnav .bd-bank-link{display:none}.bd-language{font-size:10px}.bd-account{font-size:10px;padding:7px 10px;gap:5px}.bd-main{width:calc(100% - 28px);padding:22px 0 38px}.bd-directory-hero{padding:26px 13px 18px;border-radius:18px;outline-offset:4px}.bd-paper:after{inset:4px;border-radius:14px}.bd-eyebrow{font-size:8px;letter-spacing:.12em}.bd-directory-hero>.bd-eyebrow{font-size:7px;letter-spacing:.13em;gap:8px}.bd-directory-hero>.bd-eyebrow>span{width:21px}.bd-directory-hero h1{font-size:clamp(24px,6.7vw,36px);letter-spacing:.025em;line-height:1.4;margin-top:9px}.bd-hero-subtitle{font-size:16px;letter-spacing:.1em}.bd-hero-description{font-size:10px;letter-spacing:0;margin-top:9px}.bd-hero-facts{gap:14px;margin:17px 0 13px}.bd-hero-facts>span{font-size:9px;gap:4px}.bd-hero-facts b{font-size:21px}.bd-hero-facts>i{height:15px}.bd-hero-orbit{right:-190px;top:-180px}.bd-progress-line{font-size:8px;gap:10px;padding-top:12px}.bd-progress-line small{display:none}.bd-progress-line progress{width:90px;height:3px}.bd-progress-line b{margin-left:5px}.bd-directory-tools{gap:9px;margin:23px 0 6px}.bd-search-form{padding:5px 5px 5px 10px;gap:8px;border-radius:10px}.bd-search-form input{font-size:11px;padding:5px 0}.bd-search-form>.bd-icon{width:15px;height:15px}.bd-search-form button{font-size:10px;padding:6px 12px;border-radius:7px}.bd-result-label{font-size:9px}.bd-result-label b{font-size:12px}.bd-system-nav{top:66px;gap:6px;padding:10px 0 11px;margin-right:-14px;padding-right:14px}.bd-system-nav>a{font-size:10px;padding:6px 12px}.bd-system{margin:18px 0 28px;scroll-margin-top:130px}.bd-system-heading{padding:0 1px 10px;margin-bottom:13px}.bd-system-heading>div{gap:8px}.bd-system-heading small{font-size:7px;letter-spacing:.1em}.bd-system-heading h2{font-size:18px}.bd-system-heading>span{font-size:8px}.bd-condition-grid{gap:10px}.bd-condition-card{padding:12px 10px 9px;min-height:166px;border-radius:12px}.bd-condition-card:before{inset:3px;border-radius:9px}.bd-condition-card:after{inset:-3px;border-radius:15px}.bd-card-top{gap:3px;margin-bottom:7px}.bd-organ-ring{width:44px;height:44px;box-shadow:inset 0 0 0 3px #fffffa70}.bd-organ-ring>.bd-icon{width:36px;height:36px}.bd-organ-ring:after{width:3px;height:3px;top:4px;right:0}.bd-card-number{font-size:9px;padding-top:1px}.bd-condition-card h3{font-size:13.5px;line-height:1.18;margin:2px 0 4px}.bd-condition-card p{font-size:11px;line-height:1.4;margin-bottom:12px;font-weight:600}.bd-card-bottom{gap:4px;padding-top:6px}.bd-card-state{font-size:7px;letter-spacing:0}.bd-card-direction{width:18px;height:18px}.bd-card-direction>.bd-icon{width:12px;height:12px}.bd-directory-footnote{font-size:8px;margin:26px 8px 0}.bd-site-footer{padding:25px 18px}.bd-site-footer>span{font-size:20px}.bd-site-footer p{font-size:9px}.bd-site-footer small{font-size:6px}.bd-trail{font-size:10px;gap:10px;margin-bottom:15px}.bd-trail>span{padding-left:10px}.bd-trail>small{font-size:10px}.bd-lesson-heading{padding:21px 17px;gap:14px;border-radius:17px;flex-wrap:wrap;margin-bottom:15px}.bd-lesson-organ{width:53px;height:53px;flex-basis:53px;box-shadow:0 0 0 4px #e3e9d640,inset 0 0 0 3px #ffffff80}.bd-lesson-organ>.bd-icon{width:40px;height:40px}.bd-lesson-heading>div{flex:1}.bd-lesson-heading .bd-eyebrow{font-size:7px;letter-spacing:.08em}.bd-lesson-heading h1{font-size:25px;margin:3px 0}.bd-lesson-heading p{font-size:17px}.bd-complete-button{margin:0 0 0 auto;font-size:10px!important;padding:6px 11px;min-height:30px}.bd-complete-button>.bd-icon{width:15px;height:15px}.bd-lesson-tabs{gap:21px;margin:19px 0 17px;font-size:11px}.bd-lesson-tabs>a{padding:6px 0 10px}.bd-lesson-tabs span{font-size:8px;margin-left:3px}.bd-reader{padding:12px;border-radius:16px;scroll-margin-top:85px}.bd-reader-heading{padding:2px 2px 11px}.bd-reader-heading h2{font-size:13px;margin-top:4px}.bd-fullscreen{font-size:9px;padding:6px 8px;gap:4px}.bd-fullscreen>.bd-icon{width:15px;height:15px}.bd-slide-track{height:min(70svh,760px);min-height:340px;border-radius:9px}.bd-study-slide>a{padding:7px}.bd-reader-controls{min-height:68px;gap:18px;padding:11px 0}.bd-reader-controls>div{min-width:170px;font-size:18px}.bd-reader-controls small{font-size:9px}.bd-arrow{width:30px;height:30px}.bd-arrow>.bd-icon{width:17px;height:17px}.bd-thumbnails{gap:7px;padding-inline:1px}.bd-thumbnail{padding:2px;border-radius:6px;aspect-ratio:1/1.22}.bd-thumbnail>span{font-size:8px;line-height:13px;min-width:15px;bottom:2px;right:2px}.bd-reader-hint{font-size:8px;line-height:1.6;margin-top:9px}.bd-study-notes{grid-template-columns:1fr;gap:14px;scroll-margin-top:85px}.bd-study-notes>.bd-paper{padding:21px;border-radius:16px}.bd-study-notes>.bd-clinical-note{grid-column:auto}.bd-study-notes h2{font-size:21px;margin-bottom:12px}.bd-study-notes p{font-size:12px}.bd-practice-section{padding:21px;margin-top:21px;border-radius:16px;scroll-margin-top:85px}.bd-practice-section h2{font-size:20px}.bd-practice-count{font-size:29px}.bd-study-site .bd-question-list>a{grid-template-columns:28px 1fr;padding:11px;gap:9px;font-size:11px}.bd-study-site .bd-question-list>a>span{width:25px;height:25px;font-size:10px}.bd-study-site .bd-question-list i{display:none}.bd-study-site .bd-bank-tabs a{font-size:10px;padding:6px 11px}.bd-study-site .bd-bank-tabs b{font-size:9px;height:20px;min-width:20px}.bd-lesson-pager{gap:12px;margin-top:20px}.bd-lesson-pager>a{padding:13px;border-radius:11px}.bd-lesson-pager small{font-size:9px}.bd-lesson-pager b{font-size:11px;line-height:1.5}.bd-access-panel{padding:37px 22px;min-height:400px;border-radius:18px}.bd-access-panel h2{font-size:25px}.bd-access-panel>p{font-size:12px}.bd-access-actions{gap:9px}.bd-button-primary,.bd-button-secondary{font-size:11px;padding:10px 17px}.bd-access-dialog{padding:34px 23px 23px}.bd-access-dialog h2{font-size:24px}.bd-access-dialog>p{font-size:12px}.bd-access-dialog .bd-access-actions{flex-direction:column;align-items:stretch}.bd-viewer-toolbar{padding:10px 12px;gap:7px}.bd-viewer-toolbar>div:first-child{flex-direction:column;align-items:start;gap:2px}.bd-viewer-toolbar b{font-size:11px;max-width:145px}.bd-viewer-toolbar [data-viewer-counter]{font-size:10px}.bd-viewer-tools{gap:5px}.bd-viewer-tools button{height:30px;min-width:28px;padding:0 6px}.bd-viewer-tools [data-viewer-close]{margin-left:2px}.bd-viewer-tools [data-zoom=fit]{font-size:10px}.bd-viewer-stage{padding:6px}.bd-viewer-bottom{padding:10px 11px max(10px,env(safe-area-inset-bottom));gap:10px}.bd-viewer-bottom button{padding:8px;font-size:10px}.bd-viewer-bottom>span{font-size:9px;line-height:1.5}.bd-toast{font-size:11px;bottom:18px;white-space:nowrap}}
@media(max-width:359px){.bd-condition-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.bd-condition-card{min-height:170px}.bd-condition-card h3{font-size:15px}.bd-condition-card p{font-size:12px}.bd-directory-hero h1{font-size:22px}.bd-hero-description{font-size:9px}.bd-hero-facts{gap:9px}.bd-hero-facts>span{font-size:8px}.bd-hero-facts b{font-size:19px}.bd-topbar{padding-inline:12px}.bd-topnav{gap:10px}.bd-account{font-size:9px;padding:6px 8px}.bd-wordmark small{font-size:7px}.bd-viewer-toolbar b{max-width:115px}.bd-lesson-tabs{gap:16px}.bd-lesson-heading h1{font-size:22px}}
@media(prefers-reduced-motion:reduce){.bd-study-site *, .bd-study-site *:before,.bd-study-site *:after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}


/* Larger study typography, scoped to preserve the other question-bank pages. */
body.bd-study-site{font-size:17px;line-height:1.8;-webkit-text-size-adjust:100%}
.bd-study-site .bd-eyebrow{font-size:12px;letter-spacing:.12em;color:#6d7455}
.bd-wordmark small{font-size:12px;color:#5e7569}
.bd-topnav{font-size:15px}
.bd-language{font-size:14px}
.bd-account{font-size:15px;min-height:42px}
.bd-hero-subtitle{font-size:23px}
.bd-hero-description{font-size:17px;line-height:1.85;color:#586f5d}
.bd-hero-facts{flex-wrap:wrap;gap:20px}
.bd-hero-facts>span{font-size:15px;color:#5e725c}
.bd-hero-facts b{font-size:30px}
.bd-progress-line{font-size:14px;flex-wrap:wrap;color:#61745b}
.bd-progress-line small{font-size:13px;color:#6d7b63}
.bd-search-form input{font-size:17px;min-height:36px}
.bd-search-form button{font-size:15px;min-height:40px}
.bd-result-label{font-size:14px;color:#62765c}
.bd-result-label b{font-size:18px}
.bd-system-nav>a{font-size:15px;padding:9px 16px;min-height:44px}
.bd-system-heading h2{font-size:26px}
.bd-system-heading small{font-size:12px;color:#6b7e61}
.bd-system-heading p,.bd-system-heading>span{font-size:14px;color:#687b61}
.bd-condition-card{min-height:240px;padding:21px 18px 16px}
.bd-card-number{font-size:16px;color:#718466}
.bd-condition-card h3{font-size:23px;line-height:1.3}
.bd-condition-card p{font-size:18px;line-height:1.6;color:#345a42;margin-bottom:16px}
.bd-card-state{font-size:13px;color:#627b56}
.bd-card-direction{width:29px;height:29px}
.bd-directory-footnote{font-size:14px;color:#66795d}
.bd-site-footer p{font-size:15px;color:#5f7557}
.bd-site-footer small{font-size:12px;color:#6f7d61;letter-spacing:.1em}
.bd-trail{font-size:15px;flex-wrap:wrap;color:#627858}
.bd-trail>small{font-size:14px;color:#6c7b5d}
.bd-lesson-heading h1{font-size:40px;line-height:1.4}
.bd-lesson-heading p{font-size:28px;line-height:1.4;color:#52765f}
.bd-complete-button{font-size:15px!important;min-height:42px}
.bd-lesson-tabs{font-size:17px;flex-wrap:wrap;row-gap:0}
.bd-lesson-tabs span{font-size:13px}
.bd-reader-heading h2{font-size:21px;line-height:1.6}
.bd-fullscreen{font-size:15px;min-height:42px;color:#426343!important}
.bd-reader-controls{min-height:88px}
.bd-reader-controls>div{font-size:24px}
.bd-reader-controls>div>span{font-size:18px}
.bd-reader-controls small{font-size:15px;color:#5f7855;line-height:1.6}
.bd-arrow{width:42px;height:42px}
.bd-thumbnail>span{font-size:13px;line-height:21px;min-width:23px}
.bd-reader-hint{font-size:14px;line-height:1.8;color:#647858;letter-spacing:0}
.bd-study-notes h2{font-size:28px;line-height:1.45}
.bd-study-notes h3{font-size:16px;line-height:1.6;color:#426a45;margin:20px 0 9px}
.bd-study-notes p{font-size:17px;line-height:1.9;color:#48644b}
.bd-study-notes .bd-pronunciation{font-size:25px;line-height:1.6}
.bd-study-notes summary{font-size:17px;line-height:1.6;color:#426746;min-height:32px}
.bd-study-notes details small{font-size:14px;line-height:1.85;color:#68765c}
.bd-study-notes .bd-mechanism-text{font-size:17px;line-height:1.9}
.bd-practice-section h2{font-size:28px}
.bd-practice-section>p{font-size:16px;line-height:1.85;color:#5c7452}
.bd-study-site .bd-bank-tabs a{font-size:16px;padding:9px 14px}
.bd-study-site .bd-bank-tabs b{font-size:13px}
.bd-study-site .bd-question-list>a{font-size:16px;line-height:1.75}
.bd-study-site .bd-question-list>a>span{font-size:14px}
.bd-study-site .bd-question-list small{font-size:14px;color:#667b5d}
.bd-lesson-pager small{font-size:14px;color:#657951}
.bd-lesson-pager b{font-size:17px;line-height:1.6;color:#3d6644}
.bd-access-panel>p,.bd-access-dialog>p{font-size:17px;line-height:1.85;color:#596f50}
.bd-button-primary,.bd-button-secondary{font-size:16px;min-height:46px}
.bd-access-back{font-size:15px;color:#617451!important}
.bd-access-dialog .bd-gate-condition{font-size:15px;line-height:1.7;color:#6c704e}
.bd-gate-dismiss{font-size:15px!important;min-height:42px;color:#62774f}
.bd-dialog-close{min-width:42px;min-height:42px}
.bd-viewer-toolbar b{font-size:17px}
.bd-viewer-toolbar [data-viewer-counter]{font-size:15px}
.bd-viewer-tools button{height:44px;min-width:40px;font-size:20px}
.bd-viewer-tools [data-zoom=fit]{font-size:15px}
.bd-viewer-bottom button{font-size:15px;min-height:44px}
.bd-viewer-bottom>span{font-size:15px;line-height:1.6}
.bd-toast{font-size:16px;line-height:1.6}
@media(max-width:850px){
  .bd-condition-card{min-height:230px;padding:17px 12px 13px}
  .bd-condition-card h3{font-size:20px}
  .bd-condition-card p{font-size:17px}
}
@media(max-width:600px){
  .bd-study-site .bd-eyebrow{font-size:11px;letter-spacing:.07em}
  .bd-wordmark small{font-size:10px;letter-spacing:.04em}
  .bd-topnav{font-size:14px;gap:11px}
  .bd-language{font-size:14px}
  .bd-account{font-size:13px;padding:8px 10px;min-height:40px}
  .bd-hero-subtitle{font-size:20px;letter-spacing:.06em}
  .bd-hero-description{font-size:16px;line-height:1.85}
  .bd-hero-facts{gap:10px;row-gap:7px}
  .bd-hero-facts>span{font-size:13px;gap:4px}
  .bd-hero-facts b{font-size:26px}
  .bd-hero-facts>i{display:none}
  .bd-progress-line{font-size:13px;gap:10px}
  .bd-directory-tools{align-items:stretch;flex-wrap:wrap;gap:8px}
  .bd-search-form{flex:1 1 100%}
  .bd-search-form input{font-size:16px}
  .bd-search-form button{font-size:14px;padding:8px 13px}
  .bd-result-label{font-size:13px;margin-left:auto}
  .bd-system-nav>a{font-size:14px;padding:8px 13px;min-height:42px}
  .bd-system-heading{align-items:baseline;gap:8px}
  .bd-system-heading h2{font-size:23px}
  .bd-system-heading small{font-size:11px;letter-spacing:.04em}
  .bd-system-heading>span{font-size:12px;white-space:nowrap}
  .bd-condition-card{min-height:235px;padding:13px 8px 11px}
  .bd-card-top{gap:4px}
  .bd-card-number{font-size:14px}
  .bd-condition-card h3{font-size:17px;line-height:1.35;margin:3px 0 7px}
  .bd-condition-card p{font-size:16px;line-height:1.6;margin-bottom:14px}
  .bd-card-bottom{gap:3px;flex-wrap:wrap}
  .bd-card-state{font-size:12px;letter-spacing:0}
  .bd-card-direction{width:23px;height:23px;margin-left:auto}
  .bd-directory-footnote{font-size:13px;line-height:1.9}
  .bd-site-footer p{font-size:14px;letter-spacing:0}
  .bd-site-footer small{font-size:11px;letter-spacing:.05em}
  .bd-trail{font-size:13px;gap:10px;row-gap:5px}
  .bd-trail>span{padding-left:10px}
  .bd-trail>small{font-size:13px}
  .bd-lesson-heading .bd-eyebrow{font-size:10px;letter-spacing:.04em}
  .bd-lesson-heading h1{font-size:31px}
  .bd-lesson-heading p{font-size:23px;line-height:1.45}
  .bd-complete-button{font-size:14px!important;min-height:40px;padding:7px 12px}
  .bd-lesson-tabs{font-size:16px;gap:17px}
  .bd-lesson-tabs span{font-size:12px}
  .bd-reader-heading{gap:8px}
  .bd-reader-heading h2{font-size:18px}
  .bd-fullscreen{font-size:14px;padding:7px 9px;min-height:40px}
  .bd-reader-controls{gap:12px;padding:12px 0;min-height:86px}
  .bd-reader-controls>div{min-width:0;flex:1;font-size:23px}
  .bd-reader-controls>div>span{font-size:17px}
  .bd-reader-controls small{font-size:14px;line-height:1.6}
  .bd-arrow{width:40px;height:40px;flex:0 0 40px}
  .bd-thumbnail>span{font-size:12px;line-height:19px;min-width:20px;padding:0 2px}
  .bd-reader-hint{font-size:13px;line-height:1.8}
  .bd-study-notes>.bd-paper{padding:22px 20px}
  .bd-study-notes h2{font-size:26px}
  .bd-study-notes h3{font-size:16px}
  .bd-study-notes p,.bd-study-notes .bd-mechanism-text{font-size:16px;line-height:1.95}
  .bd-study-notes .bd-pronunciation{font-size:24px}
  .bd-study-notes summary{font-size:16px;line-height:1.7;min-height:34px}
  .bd-study-notes details small{font-size:14px}
  .bd-practice-section h2{font-size:25px}
  .bd-practice-section>p{font-size:16px}
  .bd-study-site .bd-bank-tabs a{font-size:15px;padding:9px 12px}
  .bd-study-site .bd-bank-tabs b{font-size:13px}
  .bd-study-site .bd-question-list>a{font-size:16px;grid-template-columns:28px minmax(0,1fr);gap:9px}
  .bd-study-site .bd-question-list>a>span{font-size:13px}
  .bd-study-site .bd-question-list small{font-size:14px}
  .bd-lesson-pager small{font-size:13px}
  .bd-lesson-pager b{font-size:16px;line-height:1.7}
  .bd-access-panel>p,.bd-access-dialog>p{font-size:16px;line-height:1.9}
  .bd-button-primary,.bd-button-secondary{font-size:16px;padding:11px 17px}
  .bd-access-dialog .bd-gate-condition{font-size:15px}
  .bd-access-back{font-size:14px}
  .bd-viewer-toolbar{padding:10px 10px;gap:7px}
  .bd-viewer-toolbar b{font-size:14px;max-width:125px}
  .bd-viewer-toolbar [data-viewer-counter]{font-size:13px}
  .bd-viewer-tools{gap:4px}
  .bd-viewer-tools button{height:42px;min-width:34px;padding:0 7px;font-size:19px}
  .bd-viewer-tools [data-zoom=fit]{font-size:14px}
  .bd-viewer-bottom{gap:8px}
  .bd-viewer-bottom button{font-size:14px;padding:8px;min-height:44px}
  .bd-viewer-bottom>span{font-size:13px;line-height:1.5}
  .bd-toast{font-size:15px;white-space:normal}
}
@media(max-width:359px){
  .bd-condition-card{min-height:235px}
  .bd-condition-card h3{font-size:18px}
  .bd-condition-card p{font-size:16px}
  .bd-viewer-toolbar b{max-width:90px}
}

/* The desktop canvas follows each original's own aspect ratio. */
.bd-slide-track{height:auto;min-height:0;aspect-ratio:var(--bd-slide-ratio,2 / 3)}
.bd-study-slide>a{padding:0}
.bd-study-slide img{display:block;object-fit:contain}
.bd-mobile-back,.bd-reader-mobile-title,.bd-mobile-reader-actions{display:none}
.bd-reader-heading>div{min-width:0}
/* The lesson opens as one screen of swipeable original artwork on phones. */
@media(max-width:600px){
  body.bd-lesson-page .bd-topbar{display:none}
  .bd-lesson-page .bd-main-detail{width:100%;padding:0 0 28px;max-width:none}
  .bd-lesson-page .bd-trail,.bd-lesson-page .bd-lesson-tabs{display:none}
  .bd-lesson-page .bd-lesson-heading{position:absolute;width:1px;height:1px;min-height:0;margin:0;padding:0;overflow:hidden;clip:rect(0,0,0,0);border:0}
  .bd-lesson-page .bd-lesson-heading .bd-complete-button{display:none}
  .bd-lesson-page .bd-lesson-layout{display:block}
  .bd-lesson-page .bd-reader{display:flex;flex-direction:column;width:100%;height:100vh;height:100svh;min-height:0;margin:0;padding:env(safe-area-inset-top) 0 env(safe-area-inset-bottom);border:0;border-radius:0;background:linear-gradient(150deg,#f8f8ef,#ecf0e4);box-shadow:none;scroll-margin-top:0}
  .bd-lesson-page .bd-reader:after{display:none}
  .bd-lesson-page .bd-reader-heading{flex:0 0 auto;gap:9px;padding:10px 12px;min-height:70px;border-bottom:1px solid #d4ddc9;background:#fdfcf5}
  .bd-lesson-page .bd-reader-heading>div{flex:1}
  .bd-lesson-page .bd-reader-heading .bd-eyebrow,.bd-reader-desktop-title{display:none}
  .bd-mobile-back{display:grid;place-items:center;flex:0 0 38px;width:38px;height:42px;border:1px solid #d7dfcb;border-radius:50%;font:23px/1 Georgia,serif;text-decoration:none;color:#315d47}
  .bd-reader-mobile-title{display:flex;flex-direction:column;gap:2px;min-width:0}
  .bd-reader-mobile-title>b{font:600 22px/1.35 "Songti SC","Noto Serif SC",Georgia,serif;color:#153f32;overflow-wrap:anywhere}
  .bd-reader-mobile-title>span{font:500 16px/1.35 Georgia,serif;color:#52775f;overflow-wrap:anywhere}
  .bd-lesson-page .bd-reader-heading h2{margin:0}
  .bd-lesson-page .bd-fullscreen{flex:0 0 auto;font-size:14px;gap:4px;padding:6px 8px;min-height:42px;max-width:96px;white-space:normal;line-height:1.4}
  .bd-lesson-page .bd-slide-track{flex:1 1 0;height:0;min-height:0;max-height:none;width:100%;aspect-ratio:auto;border:0;border-radius:0;box-shadow:none;background:#e9eddf}
  .bd-lesson-page .bd-study-slide,.bd-lesson-page .bd-study-slide>a{height:100%;min-height:0;padding:0}
  .bd-lesson-page .bd-study-slide img{width:100%;height:100%;max-width:100%;max-height:100%;object-fit:contain;filter:none}
  .bd-lesson-page .bd-reader-controls{flex:0 0 auto;min-height:60px;margin:0;padding:7px 16px 3px;gap:12px}
  .bd-lesson-page .bd-reader-controls>div{font-size:20px;line-height:1.2}
  .bd-lesson-page .bd-reader-controls>div>span{font-size:16px}
  .bd-lesson-page .bd-reader-controls small{font-size:14px;line-height:1.5;margin-top:3px}
  .bd-lesson-page .bd-thumbnails{flex:0 0 24px;display:flex;justify-content:center;gap:0;margin:0;padding:0;height:24px;overflow:visible}
  .bd-lesson-page .bd-thumbnail{position:relative;flex:0 0 32px;width:32px;height:24px;min-width:32px;aspect-ratio:auto;padding:0;border:0;border-radius:0;background:transparent;box-shadow:none}
  .bd-lesson-page .bd-thumbnail img,.bd-lesson-page .bd-thumbnail>span{display:none}
  .bd-lesson-page .bd-thumbnail:after{content:"";position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);width:6px;height:6px;border-radius:8px;background:#b5c1a8;transition:width .15s,background .15s}
  .bd-lesson-page .bd-thumbnail.is-active:after{width:18px;background:#37684d}
  .bd-mobile-reader-actions{display:flex;align-items:center;justify-content:space-between;gap:12px;flex:0 0 auto;min-height:48px;padding:3px 16px 6px;border-top:1px solid #d5dec8;background:#f9faf0}
  .bd-mobile-reader-actions>a{font-size:15px;line-height:1.5;text-decoration:none;font-weight:600;color:#2f664a;display:flex;align-items:center;min-height:40px}
  .bd-mobile-reader-actions .bd-complete-button{margin:0;font-size:14px!important;min-height:38px}
  .bd-lesson-page .bd-reader-hint{display:none}
  .bd-lesson-page .bd-study-notes{margin:20px 14px 0;scroll-margin-top:12px}
  .bd-lesson-page .bd-practice-section{margin:20px 14px 0;scroll-margin-top:12px}
  .bd-lesson-page .bd-lesson-pager{margin:20px 14px 0}
}
@media(max-width:359px){
  .bd-lesson-page .bd-reader-heading{gap:7px;padding-inline:9px}
  .bd-mobile-back{flex-basis:34px;width:34px}
  .bd-reader-mobile-title>b{font-size:21px}
  .bd-reader-mobile-title>span{font-size:15px}
  .bd-lesson-page .bd-fullscreen{max-width:80px;font-size:13px}
}

/* Use the same actual logo and wording as the website homepage. */
.bd-home-brand{position:relative;gap:13px;line-height:1.3}
.bd-home-brand:before{content:"";position:absolute;inset:-8px -13px;z-index:-1;border:1px solid #a6bda426;border-radius:23px;box-shadow:0 0 0 5px #ffffff42;pointer-events:none}
.bd-home-brand .bd-home-logo{display:block;width:48px;height:48px;object-fit:contain;border-radius:14px;box-shadow:0 7px 17px #176b5220,0 0 0 4px #ffffffa8,0 0 0 5px #a8bea326}
.bd-home-brand>span{display:flex;flex-direction:column;gap:5px}
.bd-home-brand b{font:700 20px/1.3 Inter,"PingFang SC","Microsoft YaHei",Arial,sans-serif;letter-spacing:0}
.bd-home-brand small{font-size:13px;letter-spacing:.08em;color:#617b66}
/* Keep the complete poster in the desktop viewport; zoom is a separate action. */
@media(min-width:601px){
  .bd-lesson-page .bd-main-detail{padding-top:24px}
  .bd-lesson-page .bd-trail,.bd-lesson-page .bd-lesson-tabs{display:none}
  .bd-lesson-page .bd-lesson-heading{position:absolute;width:1px;height:1px;min-height:0;margin:0;padding:0;overflow:hidden;clip:rect(0,0,0,0);border:0}
  .bd-lesson-page .bd-lesson-heading .bd-complete-button{display:none}
  .bd-lesson-page .bd-reader{position:sticky;top:104px;display:flex;flex-direction:column;min-height:0;height:calc(100vh - 128px);height:calc(100svh - 128px);padding:14px}
  .bd-lesson-page .bd-reader-heading{flex:0 0 auto;gap:12px;min-height:64px;padding:0 3px 11px}
  .bd-lesson-page .bd-reader-heading>div{min-width:0;flex:1}
  .bd-lesson-page .bd-reader-heading .bd-eyebrow,.bd-lesson-page .bd-reader-desktop-title{display:none}
  .bd-lesson-page .bd-reader-heading h2{margin:0}
  .bd-lesson-page .bd-mobile-back{display:grid;place-items:center;flex:0 0 36px;width:36px;height:40px;border:1px solid #d3dec4;border-radius:50%;font:23px/1 Georgia,serif;text-decoration:none;color:#315d47}
  .bd-lesson-page .bd-reader-mobile-title{display:flex;flex-wrap:wrap;align-items:baseline;column-gap:12px;row-gap:2px}
  .bd-lesson-page .bd-reader-mobile-title>b{font:600 29px/1.4 "Songti SC","Noto Serif SC",Georgia,serif;overflow-wrap:anywhere}
  .bd-lesson-page .bd-reader-mobile-title>span{font:500 23px/1.4 Georgia,serif;color:#52775f;overflow-wrap:anywhere}
  .bd-lesson-page .bd-fullscreen{font-size:14px;flex:0 0 auto}
  .bd-lesson-page .bd-slide-track{flex:1 1 0;height:0;min-height:0;max-height:none;aspect-ratio:auto;width:100%;overflow-x:auto;overflow-y:hidden}
  .bd-lesson-page .bd-study-slide,.bd-lesson-page .bd-study-slide>a{height:100%;min-height:0;padding:0}
  .bd-lesson-page .bd-study-slide img{width:100%;height:100%;max-width:100%;max-height:100%;object-fit:contain;object-position:center}
  .bd-lesson-page .bd-reader-controls{flex:0 0 auto;min-height:66px;gap:18px;padding:7px 0 3px}
  .bd-lesson-page .bd-reader-controls>div{font-size:22px;line-height:1.3}
  .bd-lesson-page .bd-reader-controls small{font-size:14px;margin-top:3px}
  .bd-lesson-page .bd-thumbnails{display:flex;justify-content:center;align-items:center;gap:9px;flex:0 0 76px;height:76px;padding:5px 0 7px;overflow-x:auto}
  .bd-lesson-page .bd-thumbnail{flex:0 0 46px;width:46px;height:64px;aspect-ratio:auto;padding:2px;border-radius:7px}
  .bd-lesson-page .bd-thumbnail>span{font-size:11px;line-height:16px;min-width:18px;padding:0 2px}
  .bd-lesson-page .bd-reader-hint{display:none}
  .bd-lesson-page .bd-mobile-reader-actions{display:flex;align-items:center;justify-content:space-between;gap:12px;flex:0 0 auto;min-height:42px;padding:6px 2px 0;border-top:1px solid #d7dfc9}
  .bd-lesson-page .bd-mobile-reader-actions>a{font-size:14px;line-height:1.6;text-decoration:none;color:#446c43}
  .bd-lesson-page .bd-mobile-reader-actions .bd-complete-button{margin:0;min-height:35px;font-size:14px!important;padding:5px 11px}
}
.bd-viewer-stage{display:block;flex:1 1 0;height:0;min-height:0;overflow:hidden;padding:10px}
.bd-viewer-stage img{display:block;width:100%;height:100%;max-width:100%;max-height:100%;object-fit:contain;object-position:center}
.bd-viewer-stage.is-zoomed{overflow:auto}
.bd-viewer-stage.is-zoomed img{height:auto;max-width:none;max-height:none}
@media(max-width:1100px) and (min-width:601px){.bd-lesson-page .bd-reader-mobile-title>b{font-size:25px}.bd-lesson-page .bd-reader-mobile-title>span{font-size:20px}.bd-lesson-page .bd-reader-heading{gap:9px}}
@media(max-width:600px){
  .bd-home-brand{gap:9px}
  .bd-home-brand .bd-home-logo{width:37px;height:37px;border-radius:11px}
  .bd-home-brand b{font-size:15px}
  .bd-home-brand small{font-size:10px;letter-spacing:.03em}
  .bd-topnav{gap:10px}
  .bd-topnav .bd-account{font-size:12px;padding:7px 9px}
  .bd-viewer-stage{padding:0}
}
@media(max-width:359px){.bd-home-brand b{font-size:14px}.bd-topnav .bd-language{display:none}.bd-topbar{gap:10px;padding-inline:12px}}

/* 20261016: vertical thumbnails reserve height for the complete original. */
@media(min-width:601px){
 .bd-lesson-page .bd-main-detail{width:calc(100% - 40px);max-width:1680px;padding-top:16px}
 .bd-lesson-page .bd-lesson-layout{grid-template-columns:minmax(0,1fr) minmax(260px,310px);gap:20px}
 .bd-lesson-page .bd-reader{top:96px;height:calc(100vh - 112px);height:calc(100svh - 112px);padding:10px;display:grid;grid-template-columns:76px minmax(0,1fr);grid-template-rows:auto minmax(0,1fr) 44px;gap:6px 10px;overflow:hidden}
 .bd-lesson-page .bd-reader-heading{grid-column:1/-1;grid-row:1;min-height:48px;padding:0 2px 5px}
 .bd-lesson-page .bd-thumbnails{grid-column:1;grid-row:2/4;display:flex;flex-direction:column;justify-content:flex-start;align-items:center;gap:10px;width:76px;height:100%;min-height:0;padding:5px 4px;overflow-x:hidden;overflow-y:auto;scrollbar-width:thin}
 .bd-lesson-page .bd-thumbnail{flex:0 0 88px;width:62px;height:88px;min-height:88px;aspect-ratio:auto;padding:2px}
 .bd-lesson-page .bd-slide-track{grid-column:2;grid-row:2;width:100%;height:100%;min-width:0;min-height:0;aspect-ratio:auto}
 .bd-lesson-page .bd-study-slide>a{display:flex;width:100%;height:100%;padding:0}
 .bd-lesson-page .bd-study-slide img{width:100%;height:100%;object-fit:contain}
 .bd-lesson-page .bd-reader-controls{grid-column:2;grid-row:3;min-height:0;height:44px;padding:0;gap:16px}
 .bd-lesson-page .bd-reader-controls>div{font-size:19px;display:flex;align-items:center;justify-content:center;gap:7px}
 .bd-lesson-page .bd-reader-controls small{font-size:14px;margin:0}
 .bd-lesson-page .bd-mobile-reader-actions{display:none}
}
@media(min-width:601px) and (max-width:1000px){
 .bd-lesson-page .bd-lesson-layout{grid-template-columns:minmax(0,1fr)}
 .bd-lesson-page .bd-reader{position:relative;top:auto}
 .bd-lesson-page .bd-study-notes{grid-template-columns:1fr 1fr}
}

/* PMING 2026: maximize desktop biomedical lesson image real estate. */
@media(min-width:1001px){
 .bd-lesson-page .bd-main-detail{width:calc(100% - 24px);max-width:1920px;padding-top:8px}
 .bd-lesson-page .bd-lesson-layout{grid-template-columns:minmax(0,1fr) clamp(220px,17vw,280px);gap:12px}
 .bd-lesson-page .bd-reader{top:76px;height:calc(100svh - 86px);padding:6px;grid-template-columns:67px minmax(0,1fr);gap:4px 7px}
 .bd-lesson-page .bd-reader-heading{min-height:46px}
 .bd-lesson-page .bd-thumbnails{width:67px;padding-inline:1px}
 .bd-lesson-page .bd-thumbnail{width:57px;flex-basis:82px;height:82px}
 .bd-lesson-page .bd-slide-track{width:100%;height:100%}
 .bd-lesson-page .bd-study-slide img{max-width:100%;max-height:100%;object-fit:contain}
}


/* PMING biomedical immersive reader — 2026-10-16.
   Only authorized image lessons change; the directory and access pages remain intact. */
body.bd-immersive{background:#f7f5ef}
.bd-immersive .bd-main-detail{width:calc(100% - 20px);max-width:none;padding:8px 0 30px}
.bd-immersive .bd-trail,.bd-immersive .bd-lesson-tabs,.bd-immersive .bd-lesson-heading{display:none}
.bd-immersive .bd-lesson-layout{display:grid;grid-template-columns:minmax(0,1.12fr) minmax(350px,.88fr);gap:12px;align-items:stretch;height:calc(100vh - 16px);height:calc(100svh - 16px);min-height:490px}
.bd-immersive .bd-reader{position:relative;top:auto;display:block;height:100%;min-width:0;min-height:0;margin:0;padding:0;border:1px solid #e0e5d8;border-radius:16px;background:#f7f5ef;box-shadow:none;overflow:hidden}
.bd-immersive .bd-reader:after{display:none}
.bd-immersive .bd-slide-track{position:relative;width:100%;height:100%;min-height:0;max-height:none;aspect-ratio:auto;margin:0;padding:0;overflow-x:auto;overflow-y:hidden;background:#f7f5ef;border:0;border-radius:0;box-shadow:none;scroll-snap-type:x mandatory}
.bd-immersive .bd-study-slide,.bd-immersive .bd-study-slide>a{height:100%;min-height:0;width:100%;padding:0}
.bd-immersive .bd-study-slide img{width:100%;height:100%;max-width:100%;max-height:100%;object-fit:contain;object-position:center;filter:none}
.bd-immersive .bd-reader-controls{position:absolute;z-index:4;inset:0;display:block;width:auto;height:auto;min-height:0;margin:0;padding:0;pointer-events:none}
.bd-immersive .bd-reader-controls .bd-arrow{position:absolute;top:50%;transform:translateY(-50%);display:grid;place-items:center;width:42px;height:56px;min-height:0;border:1px solid #cbd9cf;border-radius:999px;background:#fffef0ee;color:#255b46;box-shadow:0 4px 18px #193c2530;pointer-events:auto;cursor:pointer}
.bd-immersive .bd-reader-controls .bd-arrow-left{left:10px}
.bd-immersive .bd-reader-controls .bd-arrow-right{right:10px}
.bd-immersive .bd-arrow:disabled{opacity:.3;cursor:not-allowed}
.bd-immersive .bd-reader-controls .bd-arrow-left>.bd-icon{transform:rotate(180deg)}
.bd-immersive .bd-reader-controls .bd-arrow>.bd-icon{width:24px;height:24px}
.bd-immersive .bd-immersive-zoom{position:absolute;right:15px;top:15px;z-index:5;display:flex;align-items:center;gap:6px;background:#fffff0e9;border:1px solid #d7e0d7;border-radius:999px;padding:7px 12px;font-size:12px;box-shadow:0 2px 12px #15382d16}
.bd-immersive .bd-thumbnails,.bd-immersive .bd-mobile-reader-actions,.bd-immersive .bd-reader-hint{display:none!important}
.bd-immersive .bd-study-notes{display:flex;flex-direction:column;gap:0;min-width:0;min-height:0;height:100%;overflow-y:auto;overscroll-behavior:contain;scrollbar-color:#c9d7ca transparent;background:#fff;border:1px solid #e0e5d8;border-radius:16px;box-shadow:none;scroll-margin-top:0}
.bd-immersive .bd-notes-intro{padding:18px 22px 16px;background:#fff;flex:0 0 auto;border-bottom:1px solid #e3e9e2}
.bd-immersive .bd-notes-brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:#143e32;min-width:0}
.bd-immersive .bd-notes-brand img{display:block;width:46px;height:46px;object-fit:contain;flex:0 0 46px}
.bd-immersive .bd-notes-brand span{display:flex;flex-direction:column;min-width:0}
.bd-immersive .bd-notes-brand b{font-size:16px;line-height:1.4}
.bd-immersive .bd-notes-brand small{font-size:11px;color:#648073}
.bd-immersive .bd-notes-nav{display:flex;flex-wrap:wrap;gap:8px;margin:12px 0 18px}
.bd-immersive .bd-notes-nav a{padding:5px 10px;background:#f2f7f3;border:1px solid #e0e9e2;border-radius:999px;color:#346750;text-decoration:none;font-size:12px}
.bd-immersive .bd-notes-kicker{font:700 11px/1.5 Inter,Arial,sans-serif;color:#728f7d;letter-spacing:.12em}
.bd-immersive .bd-notes-intro h1{margin:4px 0;font:700 clamp(23px,2vw,32px)/1.35 "Songti SC","Noto Serif SC",Georgia,serif;overflow-wrap:anywhere}
.bd-immersive .bd-notes-english{margin:0 0 11px;font-size:16px;line-height:1.5;color:#4e735c;overflow-wrap:anywhere}
.bd-immersive .bd-note-slide-status{display:flex;flex-wrap:wrap;align-items:baseline;gap:8px;margin:0;color:#507865;font-size:13px}
.bd-immersive .bd-note-slide-status strong{font-size:18px}
.bd-immersive .bd-note-slide-status span{font-size:13px;color:#778d79;line-height:1.5}
.bd-immersive .bd-study-notes>.bd-paper{flex:0 0 auto;padding:21px 24px;border:0;border-bottom:1px solid #e5ebe4;border-radius:0;background:#fff;box-shadow:none}
.bd-immersive .bd-study-notes>.bd-paper:after{display:none}
.bd-immersive .bd-study-notes h2{font-size:23px;margin:4px 0 12px}
.bd-immersive .bd-study-notes h3{font-size:15px;margin:14px 0 7px}
.bd-immersive .bd-study-notes p{font-size:16px;line-height:1.75;color:#395f4e;overflow-wrap:anywhere}
.bd-immersive .bd-study-notes .bd-pronunciation{font-size:23px}
.bd-immersive .bd-study-notes summary{font-size:15px;line-height:1.6}
.bd-immersive .bd-study-notes details small{font-size:13px}
.bd-immersive .bd-study-notes .bd-mechanism-text{font-size:15px;line-height:1.75}
.bd-immersive .bd-lesson-pager{margin-top:18px}
@media(min-width:1500px){.bd-immersive .bd-lesson-layout{grid-template-columns:minmax(0,1.05fr) minmax(420px,.95fr)}}
@media(min-width:601px) and (max-width:1050px){.bd-immersive .bd-lesson-layout{grid-template-columns:minmax(0,1fr) minmax(320px,.82fr);gap:8px}.bd-immersive .bd-main-detail{width:calc(100% - 14px)}.bd-immersive .bd-notes-intro{padding:12px 16px}.bd-immersive .bd-study-notes>.bd-paper{padding:16px}.bd-immersive .bd-study-notes p{font-size:14px}}
@media(max-width:600px){
 body.bd-immersive{background:#f7f5ef}
 .bd-immersive .bd-main-detail{width:100%;padding:0 0 28px}
 .bd-immersive .bd-lesson-layout{display:flex;flex-direction:column;gap:0;height:auto;min-height:0}
 .bd-immersive .bd-reader{position:relative;flex:none;width:100%;height:calc(100svh - 6px);min-height:0;padding:0;border:0;border-radius:0}
 .bd-immersive .bd-slide-track{flex:none;height:100%;min-height:0;background:#f7f5ef}
 .bd-immersive .bd-study-slide img{width:100%;height:100%;object-fit:contain}
 .bd-immersive .bd-reader-controls{inset:0}
 .bd-immersive .bd-reader-controls .bd-arrow{width:36px;height:45px}
 .bd-immersive .bd-reader-controls .bd-arrow-left{left:3px}
 .bd-immersive .bd-reader-controls .bd-arrow-right{right:3px}
 .bd-immersive .bd-immersive-zoom{right:10px;top:10px;padding:5px 8px}
 .bd-immersive .bd-study-notes{height:auto;max-height:none;overflow:visible;border:0;border-radius:0;margin:0;padding:0}
 .bd-immersive .bd-notes-intro{padding:17px 20px}
 .bd-immersive .bd-notes-intro h1{font-size:26px}
 .bd-immersive .bd-study-notes>.bd-paper{padding:18px 20px;border-radius:0;margin:0}
 .bd-immersive .bd-study-notes p{font-size:15px}
 .bd-immersive .bd-practice-section{margin:18px 12px 0}
 .bd-immersive .bd-lesson-pager{margin:18px 12px 0}
}