:root{
  --teal-900:#115e59;--teal-800:#0f766e;--teal-700:#0d9488;--teal-600:#14b8a6;--teal-100:#ccfbf1;--teal-50:#f0fdfa;
  --ink:#24323b;--ink-soft:#455761;--muted:#71818a;--bg:#f5f8f8;--surface:#fff;--line:#e3ebea;
  --danger:#dc3f45;--warning:#b7791f;--warning-bg:#fff7df;
  --radius-sm:10px;--radius:16px;--radius-lg:24px;--shadow:0 8px 28px rgba(23,61,67,.08);--shadow-hover:0 14px 34px rgba(23,61,67,.14);
  --space-1:8px;--space-2:12px;--space-3:16px;--space-4:24px;--space-5:32px;--space-6:48px
}
*{box-sizing:border-box}
html{background:var(--bg);color-scheme:light}
body{margin:0;font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--bg);font-size:15px;line-height:1.55}
a{color:inherit;text-decoration:none}button,input,select{font:inherit}button,a{-webkit-tap-highlight-color:transparent}
h1,h2,h3,p{margin-top:0}h1{font-size:clamp(28px,3vw,38px);line-height:1.2;letter-spacing:-.02em}h2{font-size:20px;line-height:1.3}p{color:var(--ink-soft)}
.eyebrow{display:block;margin-bottom:5px;color:var(--teal-700);font-size:11px;font-weight:800;letter-spacing:.13em}.subtle,.hint{color:var(--muted);font-size:13px}
.btn,.primary-btn,.ghost-btn,.danger-btn,.danger-link{min-height:42px;border-radius:var(--radius-sm);padding:10px 17px;border:1px solid transparent;display:inline-flex;align-items:center;justify-content:center;gap:7px;font-weight:700;line-height:1.2;cursor:pointer;transition:.18s ease}
.btn:hover,.primary-btn:hover,.ghost-btn:hover,.danger-btn:hover,.danger-link:hover{transform:translateY(-1px)}
.btn-primary,.primary-btn{background:var(--teal-700);border-color:var(--teal-700);color:#fff;box-shadow:0 6px 14px rgba(13,148,136,.2)}
.btn-secondary,.ghost-btn{background:#fff;border-color:var(--teal-700);color:var(--teal-800)}
.btn-danger,.danger-btn,.danger-link{background:var(--danger);border-color:var(--danger);color:#fff}
.btn-light{background:rgba(255,255,255,.16);border-color:rgba(255,255,255,.6);color:#fff}.small,.primary-btn.small{min-height:38px;padding:8px 14px}.ghost-btn:disabled,.btn:disabled{opacity:.5;cursor:not-allowed;transform:none}
.text-link{color:var(--teal-800);font-weight:700}.text-link.inline{display:inline;margin:0}
.surface-card,.panel,.stat,.class-card,.train-card,.content-book-group,.content-filters{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}
.surface-card,.panel,.train-card{padding:var(--space-4);margin-bottom:var(--space-4)}
.section-heading,.panel-title,.train-head{display:flex;justify-content:space-between;align-items:center;gap:var(--space-3);margin-bottom:var(--space-3)}
.section-heading h1,.section-heading h2,.panel-title h2,.train-head strong{margin:0}.section-heading>span,.panel-title>span,.train-head>span{color:var(--muted);font-size:13px}
.empty-state{padding:36px;text-align:center;color:var(--muted)}.empty-state.compact{padding:20px}.empty-cell{text-align:center;color:var(--muted)}

/* Brand */
.brand-lockup{display:inline-flex;align-items:center;gap:10px;min-width:0}.brand-lockup img{width:38px;height:38px;object-fit:contain}.brand-wording{display:grid;line-height:1.12}.brand-wording strong{font-family:Georgia,serif;font-size:14px;letter-spacing:.06em}.brand-wording small{margin-top:3px;font-size:9px;letter-spacing:.18em;color:var(--muted)}.brand-lockup-full img{width:64px;height:64px}.brand-lockup-full .brand-wording strong{font-size:21px}.brand-lockup-full .brand-wording small{font-size:11px}.brand-lockup-light .brand-wording strong,.brand-lockup-light .brand-wording small{color:#fff}

/* Public course home */
.app-shell{min-height:100vh;padding-bottom:82px;background:linear-gradient(180deg,#eefbf8 0,#fff 360px)}
.public-topbar{min-height:92px;padding:16px clamp(18px,4vw,56px);background:linear-gradient(135deg,var(--teal-800),var(--teal-600));color:#fff;display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:20px}
.public-page-name{display:grid;text-align:center}.public-page-name small{font-size:11px;opacity:.78;letter-spacing:.12em}.public-page-name strong{font-size:18px}.public-account{justify-self:end;display:flex;align-items:center;gap:10px}.public-account>span{display:grid}.public-account small{opacity:.75}.book-tabs{height:64px;background:rgba(255,255,255,.9);border-bottom:1px solid var(--line);display:grid;grid-template-columns:repeat(4,1fr);overflow-x:auto;position:sticky;top:0;z-index:9}.book-tab{display:flex;justify-content:center;align-items:center;white-space:nowrap;color:var(--ink-soft);font-weight:650;border-bottom:3px solid transparent}.book-tab.active{color:var(--teal-800);border-bottom-color:var(--teal-600)}
.home-content{max-width:1080px;margin:auto;padding:48px 28px 64px}.home-content>h1{text-align:center;margin-bottom:8px}.entry-link{text-align:center;color:var(--teal-800);font-weight:700;margin-bottom:28px}.install-row{text-align:center;margin-bottom:30px}.install-btn{background:#fff;color:var(--teal-800);border:1px solid var(--teal-600);border-radius:999px;padding:11px 22px;font-weight:700;cursor:pointer;box-shadow:var(--shadow)}.ios-hint{color:var(--muted);font-size:13px}
.module-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:28px}.module-card{overflow:hidden;background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);box-shadow:var(--shadow);transition:.22s ease}.module-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-hover)}.module-art{height:280px;position:relative;overflow:hidden;background:var(--teal-50)}.module-art-img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;object-position:center 18%}.module-label{padding:18px 20px;display:grid;grid-template-columns:auto 1fr;column-gap:14px;align-items:center}.module-label strong{grid-row:span 2;font-size:30px;color:var(--teal-800)}.module-label .tiny-book{color:var(--teal-600)}.module-label span:last-child{color:var(--ink-soft);font-weight:650}.art-copy{position:absolute;inset:24px;z-index:1;display:flex;justify-content:space-between}.art-copy b{font:700 24px/1.2 Georgia,serif}.art-copy span{font:italic 16px Georgia,serif}.bottom-record{position:fixed;left:0;right:0;bottom:0;z-index:20;height:68px;background:var(--teal-800);color:#fff;display:grid;place-items:center;font-weight:700}

/* Staff shell */
.role-shell{min-height:100vh;display:grid;grid-template-columns:248px minmax(0,1fr)}.role-sidebar{position:sticky;top:0;height:100vh;padding:22px 16px;background:#123f42;color:#fff;display:flex;flex-direction:column}.role-admin .role-sidebar{background:#17353a}.sidebar-brand{padding:0 8px 18px;border-bottom:1px solid rgba(255,255,255,.11)}.sidebar-role{padding:18px 12px 8px;color:rgba(255,255,255,.56);font-size:11px;letter-spacing:.15em}.sidebar-nav{display:grid;gap:5px}.sidebar-nav a,.sidebar-logout button{width:100%;min-height:44px;padding:10px 12px;border:0;border-radius:var(--radius-sm);background:transparent;color:#dceceb;text-align:left;display:flex;align-items:center;gap:11px;cursor:pointer}.sidebar-nav a span,.sidebar-logout button span{width:20px;text-align:center;color:#87d6cc}.sidebar-nav a:hover,.sidebar-nav a.active,.sidebar-logout button:hover{background:rgba(255,255,255,.1);color:#fff}.sidebar-logout{margin-top:auto}.role-workspace{min-width:0}.role-topbar{height:76px;padding:0 30px;background:rgba(255,255,255,.94);border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;position:sticky;top:0;z-index:20;backdrop-filter:blur(10px)}.topbar-page{display:flex;align-items:center;gap:10px}.topbar-page img{width:32px;height:32px;object-fit:contain}.topbar-page>div{display:grid}.topbar-page small{color:var(--muted);font-size:10px}.topbar-page strong{font-size:16px}.identity-chip{display:flex;align-items:center;gap:9px}.identity-chip>span:not(.identity-avatar){display:grid}.identity-chip strong{font-size:13px}.identity-chip small{color:var(--muted);font-size:11px}.identity-chip form{margin-left:8px}.identity-chip button{border:0;background:none;color:var(--teal-800);font-weight:700;cursor:pointer}.identity-avatar{width:36px;height:36px;border-radius:50%;background:var(--teal-100);color:var(--teal-800);display:grid!important;place-items:center;font-weight:800}.identity-avatar.soft{width:34px;height:34px;background:var(--teal-50)}.role-main{max-width:1500px;margin:0 auto;padding:32px}.page-heading{display:flex;justify-content:space-between;align-items:flex-end;gap:20px;margin-bottom:26px}.page-heading h1{margin:0 0 7px}.page-heading p{margin:0;color:var(--muted)}
.metric-grid,.stat-grid,.student-stat-grid{display:grid;gap:16px;margin-bottom:24px}.metric-grid.four,.stat-grid{grid-template-columns:repeat(4,minmax(0,1fr))}.student-stat-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.metric-card,.stat{min-width:0;padding:19px 20px;display:grid;gap:5px}.metric-card>span,.stat>span{color:var(--muted);font-size:13px}.metric-card strong,.stat strong{font-size:30px;line-height:1.15;color:var(--ink)}.metric-card small{color:var(--muted)}.metric-card.warning{background:var(--warning-bg);border-color:#f2dfac}.metric-card.warning strong{color:var(--warning)}
.dashboard-columns{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(340px,.85fr);gap:20px}.class-list,.attention-list{display:grid}.class-row,.attention-list a,.recent-course-row{display:grid;align-items:center;gap:12px;padding:13px 0;border-bottom:1px solid var(--line)}.class-row{grid-template-columns:42px 1fr auto}.class-row>span:nth-child(2),.attention-list a>span:nth-child(2),.recent-course-row>span:nth-child(2){display:grid}.class-row small,.attention-list small,.recent-course-row small{color:var(--muted)}.class-icon,.lesson-badge{width:40px;height:40px;border-radius:12px;background:var(--teal-50);color:var(--teal-800);display:grid;place-items:center;font-weight:800}.status-dot{font-size:12px}.status-dot.success{color:var(--teal-800)}.attention-list a{grid-template-columns:36px 1fr auto}.attention-list em{font-style:normal;color:var(--teal-800);font-size:13px}.course-status-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}.course-status-grid div,.activity-highlight div{padding:15px;border:1px solid var(--line);border-radius:var(--radius-sm);background:#f9fbfb;display:grid}.course-status-grid strong,.activity-highlight strong{font-size:24px}.course-status-grid span,.activity-highlight span{color:var(--muted);font-size:12px}.activity-highlight{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.table-person{display:flex;align-items:center;gap:10px}

/* Student shell */
.student-shell{min-height:100vh;padding-bottom:86px;background:linear-gradient(180deg,#eafbf7 0,var(--bg) 320px)}.student-topbar{height:72px;padding:0 max(18px,env(safe-area-inset-left));display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:12px;background:rgba(255,255,255,.92);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:15;backdrop-filter:blur(10px)}.student-page-title{display:grid;text-align:center}.student-page-title small{color:var(--muted);font-size:10px}.student-page-title strong{font-size:15px}.student-topbar .identity-chip{justify-self:end}.student-main{max-width:980px;margin:auto;padding:28px 22px}.student-welcome{background:linear-gradient(135deg,var(--teal-800),var(--teal-600));color:#fff;display:flex;justify-content:space-between;align-items:center;gap:20px}.student-welcome .eyebrow,.student-welcome p{color:rgba(255,255,255,.78)}.student-welcome h1{font-size:28px;margin:0 0 8px}.student-welcome p{margin:0}.streak-medal{min-width:110px;text-align:center;background:rgba(255,255,255,.13);border:1px solid rgba(255,255,255,.24);border-radius:var(--radius);padding:14px;display:grid}.streak-medal span,.streak-medal small{font-size:12px}.streak-medal strong{font-size:36px;line-height:1.05}.student-focus-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:20px}.continue-card p{min-height:46px}.course-kicker,.task-icon{padding:6px 9px;border-radius:999px;background:var(--teal-50);color:var(--teal-800);font-size:11px;font-weight:800}.task-icon{font-size:22px}.progress-line{height:9px;background:#e7efee;border-radius:999px;overflow:hidden;margin:30px 0 10px}.progress-line span{display:block;height:100%;border-radius:inherit;background:linear-gradient(90deg,var(--teal-700),var(--teal-600))}.progress-caption{display:flex;justify-content:space-between;color:var(--muted);font-size:13px}.recent-course-row{grid-template-columns:42px 1fr auto}.row-progress{color:var(--teal-800);font-weight:800}.student-bottom-nav{display:none}

/* Tables and forms */
.table-wrap{overflow:auto}table{width:100%;border-collapse:collapse;min-width:620px}th,td{padding:13px 12px;text-align:left;border-bottom:1px solid var(--line);font-size:14px}th{color:var(--muted);font-size:12px;font-weight:700;background:#f9fbfb}td a{color:var(--teal-800);font-weight:700}tbody tr:hover{background:#fbfdfd}
.class-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.class-card{padding:16px;display:grid;gap:4px}.class-card span{color:var(--muted);font-size:12px}.mistake{display:grid;grid-template-columns:90px 1fr 1fr 50px;gap:12px;padding:12px 0;border-bottom:1px solid var(--line)}.mistake span{color:var(--warning);font-size:12px}.mistake i{color:var(--teal-800);font-style:normal}.mistake em{color:var(--muted);font-style:normal}
.security-form,.admin-editor{display:grid;gap:16px;max-width:760px}.security-form label,.admin-editor label,.upload-form label,.content-filters label{display:grid;gap:7px;color:var(--ink-soft);font-size:13px;font-weight:650}.security-form input,.security-form select,.security-form textarea,.admin-editor input,.admin-editor select,.admin-editor textarea,.upload-form input,.upload-form select,.content-filters select,.table-input{width:100%;min-height:44px;border:1px solid #cfdddb;border-radius:var(--radius-sm);padding:10px 12px;background:#fff;color:var(--ink);outline:none}.security-form textarea,.admin-editor textarea{min-height:88px;resize:vertical}.security-form input:focus,.security-form select:focus,.security-form textarea:focus,.admin-editor input:focus,.admin-editor select:focus,.admin-editor textarea:focus{border-color:var(--teal-600);box-shadow:0 0 0 3px rgba(20,184,166,.12)}.form-card{max-width:820px}.student-form-card{margin:28px auto;max-width:620px}.form-grid{display:grid;grid-template-columns:repeat(2,minmax(220px,1fr));gap:18px}.editor-actions,.toolbar-actions,.inline-actions{display:flex;align-items:center;gap:10px;flex-wrap:wrap}.upload-form{display:grid;grid-template-columns:1fr auto;gap:14px;align-items:end}.compact-upload{margin-top:15px}.inline-form,.inline-actions{margin-top:12px}
.content-toolbar{display:flex;justify-content:space-between;align-items:center;gap:20px;margin-bottom:22px}.content-toolbar h1{margin:4px 0 0}.content-toolbar>div>span{color:var(--muted);font-size:13px}.content-filters{padding:16px 18px;margin-bottom:20px;display:flex;align-items:end;gap:14px;flex-wrap:wrap}.content-filters select{min-width:190px}.content-book-group{margin-bottom:18px;overflow:hidden}.book-group-head{padding:16px 20px;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;background:#f9fbfb}.book-group-head h2{margin:0}.book-group-head span{color:var(--muted)}.content-table{min-width:900px}.status-badge{display:inline-flex;border-radius:999px;padding:5px 9px;font-size:12px;font-weight:800}.status-uploaded{background:#e5f8f3;color:#087568}.status-missing_lrc,.status-missing_audio{background:var(--warning-bg);color:var(--warning)}.status-unpublished,.status-pending{background:#edf1f2;color:#596972}.manage-link{display:inline-flex;padding:7px 12px!important;border-radius:8px;background:var(--teal-800);color:#fff!important}.timeline-list{margin-top:16px;border-top:1px solid var(--line)}.timeline-row{display:grid;grid-template-columns:44px 150px 1fr;gap:12px;padding:11px 4px;border-bottom:1px solid var(--line)}.timeline-row span{color:var(--teal-800);font-weight:700}.timeline-row p{margin:0}.danger-panel{border-color:#efc5c7;background:#fffafa}.file-ok{color:var(--teal-800);font-weight:700}.file-missing{color:var(--warning);font-weight:700}.audio-placeholder{padding:18px;border:1px dashed #b9ceca;border-radius:var(--radius-sm);background:#f8fbfa;color:var(--muted)}audio{width:100%}

/* Auth and learning pages */
.auth-wrap{min-height:100vh;padding:26px;display:grid;place-items:center;background:radial-gradient(circle at top left,#d9faf3 0,transparent 40%),linear-gradient(135deg,#f4fbfa,#edf4f5)}.auth-card{width:min(470px,100%);padding:34px;background:#fff;border:1px solid var(--line);border-radius:var(--radius-lg);box-shadow:0 22px 60px rgba(17,94,89,.13)}.auth-brand{margin-bottom:24px;padding-bottom:20px;border-bottom:1px solid var(--line)}.auth-card h1{margin-bottom:6px}.auth-card>p{color:var(--muted)}.auth-card form{display:grid;gap:16px}.auth-card label{display:grid;gap:7px;color:var(--ink-soft);font-size:13px;font-weight:650}.auth-card input,.auth-card select{min-height:46px;border:1px solid #cfdddb;border-radius:var(--radius-sm);padding:10px 12px}.auth-card .text-link{display:inline-block;margin-top:17px}.demo-box{margin-top:20px;padding:14px;border-radius:var(--radius-sm);background:#f4f8f7;display:grid;gap:5px}.demo-box small{color:var(--muted)}
.page-shell{min-height:100vh}.simple-header{height:66px;padding:0 22px;background:var(--teal-800);color:#fff;display:grid;grid-template-columns:1fr auto 1fr;align-items:center}.simple-header strong{display:flex;align-items:center;gap:8px}.simple-header strong img{width:30px;height:30px;object-fit:contain;filter:drop-shadow(0 1px 2px rgba(0,0,0,.15))}.simple-header>span{text-align:right;font-size:12px}.content-narrow{max-width:900px;margin:auto;padding:30px 22px 90px}.hero-mini,.lesson-hero{padding:28px;border-radius:var(--radius-lg);margin-bottom:22px;background:linear-gradient(135deg,var(--teal-800),var(--teal-600));color:#fff;box-shadow:var(--shadow)}.hero-mini h1,.lesson-hero h1{margin:5px 0}.hero-mini p,.lesson-hero p{color:rgba(255,255,255,.82)}.pill{display:inline-flex;padding:5px 9px;border-radius:999px;background:rgba(255,255,255,.16);font-size:11px;letter-spacing:.1em}.lesson-list{display:grid;gap:12px}.lesson-row{display:grid;grid-template-columns:52px 1fr 22px;gap:14px;align-items:center;padding:17px;background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.lesson-row:hover{box-shadow:var(--shadow-hover)}.lesson-no{width:46px;height:46px;border-radius:12px;background:var(--teal-50);color:var(--teal-800);display:grid;place-items:center;font-weight:800}.lesson-row p{margin:4px 0 0;color:var(--muted);font-size:13px}.chev{color:var(--teal-700);font-size:25px}.segment-list{display:grid;gap:8px;margin-top:14px}.segment{width:100%;border:1px solid transparent;background:#f5f8f8;border-radius:12px;padding:11px 13px;display:grid;grid-template-columns:34px 1fr 32px 14px;gap:12px;align-items:center;text-align:left;cursor:pointer;transition:background .15s}.seg-seq{color:var(--teal-800);font-size:12px;font-weight:800}.seg-text{color:#4c5a61;font-weight:650;transition:color .12s}.segment.done .seg-text{color:#a9b8b4}.segment.active{background:var(--teal-50);border-color:#7dd7cc}.segment.active .seg-text{background-image:linear-gradient(90deg,var(--teal-700) 0,var(--teal-700) calc(var(--p,0)*100%),#9aa8a3 calc(var(--p,0)*100%));-webkit-background-clip:text;background-clip:text;color:transparent}
.seg-play{width:30px;height:30px;border-radius:50%;border:1.5px solid var(--teal-700);background:#fff;display:grid;place-items:center;flex:none;transition:background .15s}.seg-play::before{content:"";width:0;height:0;border-style:solid;border-width:6px 0 6px 10px;border-color:transparent transparent transparent var(--teal-700);margin-left:2px}.segment.active.playing .seg-play{background:var(--teal-700)}.segment.active.playing .seg-play::before{width:10px;height:10px;border:none;border-left:3px solid #fff;border-right:3px solid #fff;margin-left:0}
.seg-status{width:11px;height:11px;border-radius:50%;background:#c6cfcc;flex:none;transition:background .15s}.seg-status.playing{background:#e5484d;animation:seg-breathe 1.5s ease-in-out infinite}.seg-status.done{background:var(--teal-600)}
@keyframes seg-breathe{0%,100%{box-shadow:0 0 0 0 rgba(229,72,77,.4)}50%{box-shadow:0 0 0 5px rgba(229,72,77,0)}}
.lesson-toolbar{display:flex;align-items:center;gap:12px;margin-bottom:14px;flex-wrap:wrap}.seg-toggle{display:inline-flex;align-items:center;gap:8px;min-height:40px;padding:8px 18px;border:1.5px solid #b9c6c3;border-radius:999px;background:#fff;color:var(--ink-soft);font-weight:800;cursor:pointer;transition:.18s ease}.seg-toggle .seg-toggle-dot{width:10px;height:10px;border-radius:50%;background:#c3cecc;transition:.18s ease}.seg-toggle.on{background:var(--teal-700);border-color:var(--teal-700);color:#fff}.seg-toggle.on .seg-toggle-dot{background:#fff}
.record-panel{display:flex;gap:10px;flex-wrap:wrap}.check-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}.check-item{border:1px solid var(--line);background:#fff;border-radius:12px;padding:13px;color:#87949b;cursor:pointer}.check-item.done{background:var(--teal-50);border-color:#80d9ce;color:var(--teal-800)}.check-item.disabled{opacity:.55;cursor:not-allowed}
.flash-wrap{position:fixed;z-index:100;top:18px;left:50%;transform:translateX(-50%);width:min(520px,92%)}.flash{padding:12px 16px;border-radius:var(--radius-sm);background:#26343c;color:#fff;box-shadow:var(--shadow);margin-bottom:8px}.flash.success{background:var(--teal-800)}.flash.error{background:var(--danger)}

@media(max-width:1000px){.metric-grid.four,.stat-grid{grid-template-columns:repeat(2,1fr)}.dashboard-columns{grid-template-columns:1fr}.role-shell{grid-template-columns:220px 1fr}.role-main{padding:26px 22px}.activity-highlight{grid-template-columns:repeat(3,1fr)}}
@media(max-width:760px){
  body{font-size:14px}.public-topbar{min-height:70px;padding:10px 16px;grid-template-columns:1fr auto}.public-page-name{display:none}.brand-lockup-full img{width:46px;height:46px}.brand-lockup-full .brand-wording strong{font-size:15px}.brand-lockup-full .brand-wording small{font-size:8px}.public-account>span:not(.identity-avatar){display:none}.book-tabs{height:56px}.book-tab{font-size:13px}.home-content{padding:30px 14px 50px}.module-grid{gap:14px}.module-art{height:190px}.module-label{padding:13px;column-gap:9px}.module-label strong{font-size:23px}.module-label span:last-child{font-size:13px}
  .role-shell{display:block}.role-sidebar{position:static;height:auto;padding:12px 14px}.sidebar-brand,.sidebar-role,.sidebar-logout{display:none}.sidebar-nav{display:flex;overflow:auto}.sidebar-nav a{min-width:max-content}.role-topbar{height:64px;padding:0 16px}.role-topbar .identity-chip>span:not(.identity-avatar){display:none}.role-main{padding:22px 15px}.page-heading{align-items:flex-start;flex-direction:column}.metric-grid.four,.stat-grid{grid-template-columns:repeat(2,1fr)}.metric-card strong,.stat strong{font-size:25px}.form-grid{grid-template-columns:1fr}.content-toolbar{align-items:flex-start;flex-direction:column}.toolbar-actions{width:100%}.content-filters label{flex:1}.content-filters select{min-width:140px}.class-cards{grid-template-columns:1fr}
  .student-topbar{grid-template-columns:1fr auto}.student-page-title{display:none}.student-topbar .identity-chip>span:not(.identity-avatar){display:none}.student-main{padding:20px 14px}.student-welcome{padding:20px}.student-welcome h1{font-size:23px}.student-focus-grid{grid-template-columns:1fr}.student-stat-grid{grid-template-columns:repeat(3,1fr);gap:10px}.student-stat-grid .metric-card{padding:14px}.student-stat-grid .metric-card strong{font-size:23px}.student-stat-grid .metric-card small{display:none}.student-bottom-nav{position:fixed;left:0;right:0;bottom:0;z-index:40;height:calc(64px + env(safe-area-inset-bottom));padding-bottom:env(safe-area-inset-bottom);background:rgba(255,255,255,.96);border-top:1px solid var(--line);display:grid;grid-template-columns:repeat(4,1fr);box-shadow:0 -8px 24px rgba(23,61,67,.08)}.student-bottom-nav a,.student-bottom-nav form,.student-bottom-nav button{height:64px}.student-bottom-nav a,.student-bottom-nav button{border:0;background:none;color:var(--muted);display:grid;place-items:center;align-content:center;gap:1px;font-size:18px}.student-bottom-nav a.active{color:var(--teal-800)}.student-bottom-nav small{font-size:10px}.student-shell,.page-shell,.app-shell{padding-bottom:76px}
  .simple-header{height:60px;padding:0 14px}.content-narrow{padding:20px 14px 88px}.timeline-row{grid-template-columns:35px 105px 1fr}.check-grid{grid-template-columns:repeat(2,1fr)}
}
@media(max-width:480px){.module-art{height:150px}.module-label{grid-template-columns:1fr;text-align:center}.module-label strong{grid-row:auto}.module-label .tiny-book{display:none}.student-welcome{align-items:flex-start}.streak-medal{min-width:82px}.activity-highlight,.course-status-grid{grid-template-columns:1fr 1fr}.upload-form{grid-template-columns:1fr}.auth-card{padding:24px}.auth-brand .brand-lockup-full img{width:54px;height:54px}.record-panel .btn,.record-panel .primary-btn,.record-panel .ghost-btn{flex:1}}
.module-label .tiny-book{font-size:11px;font-weight:700}
/* 移动端主动安装提示横幅 */
.install-bar{position:fixed;left:50%;transform:translateX(-50%);bottom:78px;z-index:60;display:flex;align-items:center;gap:12px;max-width:calc(100vw - 28px);width:max-content;background:var(--teal-800);color:#fff;border-radius:999px;padding:12px 14px 12px 20px;box-shadow:0 12px 32px rgba(15,118,110,.35);animation:installbar-in .35s ease}
@keyframes installbar-in{from{opacity:0;transform:translate(-50%,12px)}to{opacity:1;transform:translate(-50%,0)}}
.install-bar-text{font-size:14px;font-weight:650;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.install-bar-btn{border:0;border-radius:999px;background:#fff;color:var(--teal-800);font-weight:800;padding:8px 16px;font-size:14px;cursor:pointer}
.install-bar-close{border:0;background:transparent;color:rgba(255,255,255,.75);font-size:14px;padding:4px 6px;cursor:pointer}
.ios-guide-mask{position:fixed;inset:0;z-index:80;background:rgba(15,30,35,.55);display:grid;place-items:center;padding:24px}
.ios-guide{background:#fff;border-radius:var(--radius-lg);max-width:420px;width:100%;padding:26px;box-shadow:var(--shadow-hover)}
.ios-guide strong{font-size:18px}
.ios-guide ol{margin:16px 0;padding-left:22px;display:grid;gap:10px;color:var(--ink-soft)}
.ios-guide ol b{color:var(--ink)}
.ios-guide .btn{width:100%;margin-top:6px}

/* V1.3.2 会员与班级体系：详情列表、会员提示、状态徽章、行内编辑、作业批阅 */
.detail-list{display:grid;gap:0;margin:0}.detail-list>div{display:grid;grid-template-columns:110px 1fr;gap:12px;padding:11px 0;border-bottom:1px solid var(--line)}.detail-list dt{color:var(--muted);font-size:13px}.detail-list dd{margin:0;color:var(--ink);font-weight:600}
.membership-strip{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:16px 20px;margin-bottom:20px;background:linear-gradient(135deg,var(--teal-50),#fff)}.membership-strip>div{display:grid;gap:2px}.membership-strip strong{font-size:17px;color:var(--teal-900)}.membership-strip small{color:var(--muted)}
.membership-notice{padding:13px 16px;border:1px solid #f2dfac;border-radius:var(--radius-sm);background:var(--warning-bg);color:var(--warning);font-weight:650;margin:14px 0}
.status-badge.status-active{background:#e5f8f3;color:#087568}.status-badge.status-suspended{background:#fdecea;color:#b0382f}.status-badge.status-expired{background:var(--warning-bg);color:var(--warning)}.status-badge.status-removed{background:#fdecea;color:#a0352c}.status-badge.status-approved{background:#e5f8f3;color:#087568}
.form-details summary{list-style:none;display:inline-flex;cursor:pointer}.form-details summary::-webkit-details-marker{display:none}.inline-details{position:relative;display:inline-flex}
.inline-edit-form{position:absolute;right:0;top:calc(100% + 6px);z-index:30;width:min(340px,86vw);background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow-hover);padding:14px;display:grid;gap:10px}.inline-edit-form input,.inline-edit-form textarea{width:100%;min-height:40px;border:1px solid #cfdddb;border-radius:8px;padding:8px 10px;outline:none}.inline-edit-form input:focus,.inline-edit-form textarea:focus{border-color:var(--teal-600)}.inline-edit-form textarea{min-height:64px;resize:vertical}
.inline-check{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--ink-soft)}.inline-check input{width:auto;min-height:0}
.inline-submit{display:grid;gap:8px;margin-top:8px}.inline-submit textarea{width:100%;min-height:64px;border:1px solid #cfdddb;border-radius:8px;padding:9px 11px;resize:vertical}
.submission-card{border:1px solid var(--line);border-radius:var(--radius);padding:16px;margin-bottom:12px;background:#fff}.submission-card.submitted{border-color:#bfe6de}.submission-card header{display:flex;align-items:center;gap:10px;margin-bottom:10px}.submission-card header>span:last-child{display:grid}.submission-card header small{color:var(--muted)}.submission-body p{margin:0 0 8px}.submission-body>small{color:var(--muted)}.submission-grade{margin-top:10px;padding:10px 13px;background:var(--teal-50);border-radius:var(--radius-sm);color:var(--teal-900);font-size:14px}.submission-grade strong{font-size:17px}
.class-row .inline-actions{margin-top:0;justify-content:flex-end}

/* V1.3.15 教师端班级管理：Tabs / 紧凑卡片 / 批改卡 / 通用菜单 */
.min-w-0{min-width:0}
.class-detail-heading{align-items:center}
.class-detail-meta{margin:6px 0 0;color:var(--muted);font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.tab-nav{display:flex;gap:4px;overflow-x:auto;border-bottom:1px solid var(--line);margin-bottom:18px;background:rgba(255,255,255,.7);border-radius:var(--radius) var(--radius) 0 0;padding:6px 8px 0}
.tab-nav a{padding:9px 14px;color:var(--ink-soft);font-weight:650;border-bottom:3px solid transparent;white-space:nowrap;display:flex;align-items:center;gap:6px}
.tab-nav a.active{color:var(--teal-800);border-bottom-color:var(--teal-600)}
.tab-nav a em{font-style:normal;font-size:11px;background:var(--danger);color:#fff;border-radius:999px;padding:1px 6px}
.metric-grid.four.compact .metric-card{padding:14px 16px}.metric-grid.four.compact .metric-card strong{font-size:24px}
.more-menu a.more-menu-item{display:block;text-decoration:none}
.more-menu-item[data-confirm],.more-menu-item[data-leave]{color:var(--danger)}
.grading-card{border:1px solid var(--line);border-radius:var(--radius);background:#fff;padding:20px 22px;margin-bottom:14px;box-shadow:var(--shadow)}
.grading-card.reviewed{border-color:#bfe6de;background:linear-gradient(135deg,#f6fcfb,#fff)}
.grading-card.empty{padding:14px 20px}
.grading-card>header{display:flex;align-items:center;gap:12px;margin-bottom:16px}
.grading-card.empty>header{margin-bottom:0}
.grading-card>header>span:nth-child(2){display:grid;flex:1;gap:2px}
.grading-card header small{color:var(--muted)}
.grading-body audio{width:100%;margin:2px 0 14px}
.grading-form{display:grid;gap:12px}
.grading-form .form-grid{grid-template-columns:130px 1fr;gap:14px}
.grading-form .toolbar-actions{margin-top:2px}
.grading-form textarea,.grading-edit textarea{min-height:130px;resize:vertical;line-height:1.6}
.grading-form input[type=number],.grading-edit input[type=number]{min-height:48px;font-size:16px;font-weight:700}
.grading-result-head{display:flex;align-items:flex-start;justify-content:space-between;gap:10px;margin-bottom:12px}
.grading-score{display:grid;justify-items:center;min-width:96px;padding:12px 16px;border-radius:var(--radius-sm);background:var(--teal-50);border:1px solid #bfe6de}
.grading-score small{color:var(--muted);font-size:12px}
.grading-score strong{font-size:34px;line-height:1.1;color:var(--teal-800)}
.grading-score em{font-style:normal;color:var(--muted);font-size:13px}
.grading-feedback{padding:12px 16px;background:#f9fbfb;border:1px solid var(--line);border-radius:var(--radius-sm)}
.grading-feedback .eyebrow{margin-bottom:6px}
.grading-feedback p{margin:0;white-space:pre-line;line-height:1.7}
.grading-edit{width:min(420px,92vw)}
@media(max-width:760px){
  .tab-nav a{padding:8px 11px;font-size:13px}
  .class-detail-heading{align-items:flex-start}
  .grading-form .form-grid{grid-template-columns:1fr}
  .grading-card{padding:16px 18px}
  .grading-card.empty{padding:12px 16px}
}

/* V1.3.13 课程页班级作业模式 */
.assignment-banner{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:14px 18px;margin-bottom:18px;border:1.5px solid #80d9ce;border-radius:var(--radius);background:linear-gradient(135deg,var(--teal-50),#fff)}.assignment-banner>div{display:grid;gap:3px;min-width:0}.assignment-banner strong{font-size:16px;color:var(--teal-900)}.assignment-banner small{color:var(--muted)}
.hw-success{margin-top:12px;padding:14px 16px;border:1px solid #bfe6de;border-radius:var(--radius-sm);background:var(--teal-50)}.hw-success p{margin:0 0 6px;font-weight:700;color:var(--teal-900)}
@media(max-width:760px){.assignment-banner{align-items:flex-start;flex-direction:column}}

/* V1.3.11 我的班级卡片：移动端优先（360-430px），信息一行式防竖排换行 */
.class-page-heading{align-items:center}
.btn-outline{background:#fff;border:1.5px solid #b9c6c3;color:var(--ink-soft)}
.class-card-list{display:grid;gap:14px;background:transparent;border:0;box-shadow:none;padding:0}
.class-item{background:#fff;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:16px}
.class-item-head{display:flex;align-items:center;gap:10px;min-width:0}
.class-item-name{margin:0;font-size:17px;line-height:1.3;min-width:0;flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.class-item-head .status-badge{flex:none;white-space:nowrap}
.class-item-meta{margin:8px 0 14px;color:var(--muted);font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.class-item-actions{display:flex;justify-content:flex-end;gap:8px}
.more-wrap{position:relative;flex:none}
.more-btn{width:34px;height:34px;border-radius:50%;border:1px solid var(--line);background:#fff;color:var(--ink-soft);font-size:16px;font-weight:800;cursor:pointer;display:grid;place-items:center;line-height:1;padding:0 0 4px}
.more-btn:hover{background:var(--teal-50)}
.more-menu{position:absolute;right:0;top:calc(100% + 6px);min-width:150px;background:#fff;border:1px solid var(--line);border-radius:var(--radius-sm);box-shadow:var(--shadow-hover);padding:6px;z-index:50}
.more-menu-item{width:100%;text-align:left;border:0;background:none;padding:10px 12px;border-radius:8px;color:var(--danger);font-weight:650;cursor:pointer}
.more-menu-item:hover{background:#fdf1f1}
.confirm-mask{position:fixed;inset:0;z-index:120;background:rgba(15,30,35,.5);display:grid;place-items:center;padding:24px}
.confirm-box{background:#fff;border-radius:var(--radius-lg);max-width:340px;width:100%;padding:24px;box-shadow:var(--shadow-hover)}
.confirm-box strong{font-size:17px}
.confirm-actions{display:flex;gap:10px;justify-content:flex-end;margin-top:18px}

/* V1.3.3 班级主页与公告板 */
.metric-grid.three{grid-template-columns:repeat(3,minmax(0,1fr))}
.state-card{padding:32px}.state-card p{font-size:15px;max-width:560px}
.announcement-card{border:1px solid var(--line);border-radius:var(--radius);background:#fff;padding:16px 18px;margin-bottom:12px}.announcement-card.pinned{border-color:#80d9ce;background:linear-gradient(135deg,var(--teal-50),#fff)}.announcement-card h3{margin:6px 0 8px;font-size:16px}.announcement-card p{margin:0 0 10px;white-space:pre-line}.announcement-card>small,.announcement-card header small{color:var(--muted);font-size:12px}.announcement-card header{display:flex;align-items:center;gap:10px;flex-wrap:wrap}.announcement-card header strong{font-size:16px}.announcement-card footer{display:flex;align-items:center;gap:8px;flex-wrap:wrap;margin-top:6px}
.lesson-badge.overdue{background:#fdecea;color:#b0382f}.lesson-badge.done{background:var(--teal-50);color:var(--teal-800)}
.submission-text{margin:6px 0 0;color:var(--ink-soft);font-size:13px}
@media(max-width:760px){.metric-grid.three{grid-template-columns:1fr}}