:root{--sky: #EAF6FC;--sky-strong: #7FC4E8;--teal: #2FA69A;--teal-deep: #2B7A8C;--ink: #2B4750;--sun: #F6C453;--coral: #F48B6C;--surface: #FFFFFF;--surface-2: #F7FBFA;--border: #E3EDF2;--text: #2B4750;--text-2: #6C8794;--danger: #D9534F;--success: #3BA776;--radius-s: 8px;--radius-m: 14px;--radius-l: 22px;--space-1: 4px;--space-2: 8px;--space-3: 12px;--space-4: 16px;--space-5: 24px;--space-6: 32px;--shadow-1: 0 1px 3px rgba(43, 71, 80, .08);--shadow-2: 0 4px 16px rgba(43, 71, 80, .12);--font-ui: -apple-system, "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", system-ui, sans-serif;--tap-scale: .96;--tap-duration: .12s}*{box-sizing:border-box;margin:0;padding:0}html,body{height:100%}body{font-family:var(--font-ui);background:var(--surface-2);color:var(--text);-webkit-font-smoothing:antialiased}.app{display:flex;flex-direction:column;height:100vh;height:100dvh;max-width:720px;margin:0 auto}.app-header{flex-shrink:0;padding:calc(env(safe-area-inset-top) + var(--space-3)) var(--space-4) var(--space-3);background:var(--surface);border-bottom:1px solid var(--border);display:flex;justify-content:center}.app-main{flex:1;min-height:0;overflow-y:auto;-webkit-overflow-scrolling:touch;overscroll-behavior:contain}.page{padding:var(--space-4);padding-bottom:var(--space-6)}.page-title{font-size:22px;font-weight:600;margin-bottom:var(--space-4)}.btn{font-family:var(--font-ui);font-size:15px;border:none;border-radius:var(--radius-s);padding:10px 16px;cursor:pointer;transition:transform var(--tap-duration) ease,box-shadow var(--tap-duration) ease,background var(--tap-duration) ease}.btn:active{transform:scale(var(--tap-scale))}.btn-primary{background:var(--teal);color:#fff;box-shadow:var(--shadow-1)}.btn-primary:active{background:var(--teal-deep)}.btn-secondary{background:var(--sky);color:var(--teal-deep)}.btn-danger{background:#fbeaea;color:var(--danger)}.btn-ghost{background:transparent;color:var(--text-2)}.hero-card{position:relative;background:var(--sky);border-radius:var(--radius-l);overflow:hidden;box-shadow:var(--shadow-1)}.hero-text{position:relative;z-index:1;padding:var(--space-5) var(--space-5) 84px}.hero-text h1{font-size:22px;font-weight:600;margin-bottom:var(--space-2)}.hero-text p{color:var(--text-2);font-size:15px}.hero-hills{position:absolute;left:0;right:0;bottom:0;width:100%;height:72px}.phase-note{color:var(--text-2);font-size:13px;margin:var(--space-4) var(--space-1)}.module-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:var(--space-3)}@media (min-width: 560px){.module-grid{grid-template-columns:repeat(3,1fr)}}.module-tile{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-4);display:flex;flex-direction:column;gap:var(--space-2);transition:transform var(--tap-duration) ease,box-shadow var(--tap-duration) ease}.module-tile:active{transform:scale(var(--tap-scale));box-shadow:var(--shadow-1)}.module-name{font-size:16px;font-weight:600}.module-badge{align-self:flex-start;font-size:12px;color:var(--text-2);background:var(--surface-2);border:1px solid var(--border);border-radius:999px;padding:2px 10px}.shadow-frame{position:fixed;top:0;right:0;bottom:0;left:0;border:3px solid var(--sun);pointer-events:none;z-index:90}.shadow-pill{position:fixed;left:50%;transform:translate(-50%);top:calc(env(safe-area-inset-top) + 8px);display:flex;align-items:center;gap:var(--space-2);background:#fff3d6;border:1px solid #EDD9A3;color:#8a6d1f;font-size:12.5px;font-weight:600;border-radius:999px;padding:5px 8px 5px 12px;box-shadow:var(--shadow-2);z-index:91;white-space:nowrap}.shadow-dot{width:8px;height:8px;border-radius:50%;background:var(--sun);animation:shadow-pulse 1.6s ease-in-out infinite}@keyframes shadow-pulse{0%,to{opacity:1}50%{opacity:.35}}.shadow-exit{border:1px solid #EDD9A3;background:#fffdf5;color:#8a6d1f;border-radius:999px;font-family:var(--font-ui);font-size:12px;font-weight:600;padding:4px 12px;cursor:pointer;transition:transform var(--tap-duration) ease}.shadow-exit:active{transform:scale(var(--tap-scale))}.ask-btn{font-family:var(--font-ui);font-size:13px;font-weight:600;border:1px solid var(--sky-strong);background:var(--sky);color:var(--teal-deep);border-radius:999px;padding:5px 14px;cursor:pointer;transition:transform var(--tap-duration) ease,background var(--tap-duration) ease}.ask-btn:active{transform:scale(var(--tap-scale))}.ask-btn.asked{background:#fdf3dc;border-color:#edd9a3;color:#8a6d1f}.ask-btn.replied{background:#eaf7ef;border-color:#bfe3ce;color:var(--success)}.ask-btn.compact{font-size:12px;padding:3px 10px}.player-ask{display:flex;justify-content:center;margin-top:var(--space-2)}.ask-sheet{max-height:72dvh;overflow-y:auto;-webkit-overflow-scrolling:touch;padding-bottom:calc(env(safe-area-inset-bottom) + var(--space-5))}.ask-excerpt{background:var(--surface-2);border-left:3px solid var(--sky-strong);border-radius:0 var(--radius-s) var(--radius-s) 0;padding:var(--space-2) var(--space-3);font-size:14px;margin:var(--space-2) 0;white-space:pre-wrap}.ask-my-comment{font-size:13px;color:var(--text-2);margin:var(--space-1) 0}.ask-reply{background:#eaf7ef;border-radius:var(--radius-s);padding:var(--space-2) var(--space-3);margin-top:var(--space-2);font-size:14px}.ask-reply-label{font-size:12px;font-weight:600;color:var(--success);display:block;margin-bottom:2px}.ask-row-head{display:flex;align-items:center;gap:var(--space-2)}.ask-row-head .unit-res-name{font-size:13px}.ask-status{margin-left:auto;font-size:11px;font-weight:600;color:#8a6d1f;background:#fdf3dc;border-radius:999px;padding:2px 10px}.ask-status.replied{color:var(--success);background:#eaf7ef}.res-ask-vocab_item{background:var(--sky);color:var(--teal-deep)}.res-ask-reading_sentence,.res-ask-reading_word{background:#fdf3dc;color:#9a7b1e}.res-ask-exam_question{background:#fbeaea;color:var(--danger)}.res-ask-dialogue_line{background:#eaf7ef;color:var(--success)}.note-card{border-top:1px solid var(--border);padding:var(--space-3) var(--space-1)}.note-unit{font-size:11px;font-weight:600;color:var(--teal-deep);background:var(--sky);border-radius:4px;padding:1px 6px}.note-content{font-size:15px;margin:var(--space-2) 0;white-space:pre-wrap}.note-meta{display:flex;align-items:center;justify-content:space-between;font-size:12px;color:var(--text-2);margin-top:var(--space-2)}.note-actions{display:flex;gap:2px}.asked-sentence{border-bottom:2px dotted var(--sky-strong)}.hot-sentence{cursor:pointer;background:#fffbee;border-radius:4px}.hot-chips{display:inline-flex;gap:4px;margin:0 4px;vertical-align:middle}.hot-chip{font-size:11px;font-weight:700;border-radius:999px;padding:1px 8px;white-space:nowrap}.hot-chip.mark{background:var(--sky);color:var(--teal-deep)}.hot-chip.ask{background:#eaf7ef;color:var(--success)}.hot-chip.ask.open{background:#fdf3dc;color:#8a6d1f}.weak-actions{display:flex;align-items:center;gap:var(--space-2)}.filter-btn{background:var(--surface);border:1px solid var(--border);color:var(--text-2);display:flex;align-items:center;gap:6px;white-space:nowrap}.filter-btn.active{border-color:var(--teal);color:var(--teal-deep);background:var(--sky)}.filter-count{background:var(--teal);color:#fff;font-size:11px;font-weight:700;border-radius:999px;min-width:18px;height:18px;display:inline-flex;align-items:center;justify-content:center;padding:0 5px}.fsheet-section{margin-bottom:var(--space-3)}.fsheet-title{font-size:12px;font-weight:600;color:var(--text-2);margin-bottom:6px}.used-badge{color:var(--teal-deep);font-weight:600}.unused-dim{opacity:.55}.print-root{position:fixed;top:0;right:0;bottom:0;left:0;background:#f0f2f3;z-index:200;overflow-y:auto;-webkit-overflow-scrolling:touch;padding:var(--space-3) var(--space-3) var(--space-6)}.print-toolbar{display:flex;justify-content:space-between;align-items:center;max-width:720px;margin:0 auto var(--space-2);padding-top:env(safe-area-inset-top)}.sheet{background:#fff;color:#1a1a1a;max-width:680px;margin:0 auto;padding:28px 32px 40px;border-radius:6px;box-shadow:var(--shadow-2);font-size:13px;line-height:1.65}.sheet-head{border-bottom:2px solid #1a1a1a;padding-bottom:10px;margin-bottom:18px}.sheet-head h1{font-size:19px;font-weight:700}.sheet-meta{font-size:11px;color:#555;margin-top:4px}.sheet-section{margin-bottom:22px}.sheet-section h2{font-size:15px;font-weight:700;border-left:4px solid #1a1a1a;padding-left:8px;margin-bottom:10px;break-after:avoid}.sheet-section h3{font-size:13px;font-weight:700;margin:12px 0 6px;break-after:avoid}.sheet-table{width:100%;border-collapse:collapse;font-size:12px}.sheet-table th,.sheet-table td{border:1px solid #ccc;padding:4px 6px;text-align:left;vertical-align:top}.sheet-table th{background:#f2f2f2;font-weight:600}.sheet-table tr{break-inside:avoid}.sheet-dim{color:#666;font-size:11.5px}.sheet-note{font-size:11px;color:#777;margin-top:4px}.sheet-reading p{margin-bottom:10px}.sheet-marked-word{text-decoration:underline;text-underline-offset:2px}.sheet-marked-sentence{background:#f1f1f1;box-decoration-break:clone;-webkit-box-decoration-break:clone}.sheet-list{padding-left:18px;margin:4px 0}.sheet-list li{margin-bottom:3px}.sheet-wrong{border:1px solid #ddd;border-radius:4px;padding:8px 10px;margin-bottom:8px;break-inside:avoid}.sheet-explain{color:#333;background:#f6f6f6;padding:4px 8px;border-radius:3px;margin-top:4px}.sheet-foot{margin-top:28px;padding-top:8px;border-top:1px solid #ccc;font-size:10px;color:#999;text-align:center}@media print{body *{visibility:hidden}.print-root,.print-root *{visibility:visible}.print-root{position:absolute;top:0;right:0;bottom:0;left:0;overflow:visible;background:#fff;padding:0}.no-print{display:none!important}.sheet{box-shadow:none;border-radius:0;max-width:none;padding:0}.shadow-frame,.shadow-pill{display:none!important}}.rank-badge{display:inline-flex;align-items:center;justify-content:center;width:20px;height:20px;border-radius:50%;background:var(--coral);color:#fff;font-size:12px;font-weight:700;margin-right:6px;flex-shrink:0}.wrong-bar-track{height:5px;background:var(--surface-2);border-radius:999px;margin-top:6px;overflow:hidden}.wrong-bar{height:100%;background:var(--sky-strong);border-radius:999px}.wrong-bar.high{background:var(--coral)}.unread-dot{width:8px;height:8px;border-radius:50%;background:var(--coral);display:inline-block;margin-right:6px;flex-shrink:0}.report-unread{background:#fffbf5}.weak-detail{background:var(--surface-2);border-radius:var(--radius-s);padding:var(--space-3);margin-top:var(--space-2);font-size:14px}.weak-detail .q-stem{font-weight:600;margin-bottom:var(--space-2)}.weak-option{color:var(--text-2);margin:2px 0}.weak-detail .result-lines{margin-top:var(--space-2)}.weak-detail .result-feedback{color:var(--teal-deep);margin-top:4px}.weak-actions{flex-wrap:wrap}.bubble-replay{border:none;background:transparent;cursor:pointer;font-size:15px;margin-left:6px;padding:0 2px;vertical-align:middle;transition:transform var(--tap-duration) ease}.bubble-replay:active{transform:scale(var(--tap-scale))}.bubble-replay.playing{animation:shadow-pulse 1s ease-in-out infinite}.bubble-replay:disabled{opacity:.35}.correction-actions{display:flex;gap:var(--space-2);margin-top:var(--space-2);flex-wrap:wrap}.tabbar{display:flex;flex-shrink:0;position:relative;z-index:20;background:var(--surface);border-top:1px solid var(--border);padding-bottom:env(safe-area-inset-bottom)}.tab-btn{flex:1;font-family:var(--font-ui);font-size:14px;padding:var(--space-3) 0;border:none;background:transparent;color:var(--text-2);cursor:pointer;transition:transform var(--tap-duration) ease,color var(--tap-duration) ease}.tab-btn:active{transform:scale(var(--tap-scale))}.tab-btn.active{color:var(--teal);font-weight:600}.settings-group{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-4);margin-bottom:var(--space-4)}.settings-group h2{font-size:14px;color:var(--text-2);font-weight:500;margin-bottom:var(--space-3)}.settings-row{display:flex;justify-content:space-between;align-items:center;padding:var(--space-2) 0;font-size:15px}.settings-hint{font-size:12px;color:var(--text-2);margin-top:var(--space-2)}.version-row{user-select:none;-webkit-user-select:none;-webkit-touch-callout:none;cursor:pointer}.version-value{color:var(--teal-deep);font-weight:600}.segmented{display:flex;background:var(--surface-2);border:1px solid var(--border);border-radius:var(--radius-s);padding:3px;gap:3px}.segment{flex:1;font-family:var(--font-ui);font-size:14px;padding:8px 0;border:none;border-radius:6px;background:transparent;color:var(--text-2);cursor:pointer;transition:transform var(--tap-duration) ease,background var(--tap-duration) ease,color var(--tap-duration) ease}.segment:active{transform:scale(var(--tap-scale))}.segment.active{background:var(--surface);color:var(--teal-deep);font-weight:600;box-shadow:var(--shadow-1)}.debug-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#2b475073;display:flex;align-items:flex-end;justify-content:center;z-index:100}.debug-panel{background:var(--surface);border-radius:var(--radius-l) var(--radius-l) 0 0;width:100%;max-width:720px;max-height:80dvh;display:flex;flex-direction:column;padding:var(--space-4);padding-bottom:calc(env(safe-area-inset-bottom) + var(--space-4))}.debug-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:var(--space-2)}.debug-meta{display:flex;gap:var(--space-4);font-size:12px;color:var(--text-2);margin-bottom:var(--space-3)}.debug-actions{display:flex;gap:var(--space-2);flex-wrap:wrap;margin-bottom:var(--space-3)}.debug-log-list{overflow-y:auto;font-size:12px;border-top:1px solid var(--border)}.debug-log-row{display:flex;gap:var(--space-2);padding:6px 0;border-bottom:1px solid var(--border);flex-wrap:wrap}.debug-log-time{color:var(--text-2);font-variant-numeric:tabular-nums}.debug-log-module{color:var(--teal-deep);font-weight:600}.debug-log-data{color:var(--text-2);word-break:break-all}.debug-empty{color:var(--text-2);padding:var(--space-3) 0}.error-screen{min-height:100dvh;display:flex;align-items:center;justify-content:center;padding:var(--space-4);background:var(--surface-2);font-family:var(--font-ui)}.error-card{background:var(--surface);border-radius:var(--radius-l);box-shadow:var(--shadow-2);padding:var(--space-6) var(--space-5);max-width:420px;text-align:center;display:flex;flex-direction:column;gap:var(--space-3);align-items:center}.error-icon{width:48px;height:48px;border-radius:50%;background:var(--sun);color:var(--ink);font-size:26px;font-weight:700;display:flex;align-items:center;justify-content:center}.error-card h1{font-size:18px}.error-card p{font-size:14px;color:var(--text-2)}.error-code{background:var(--surface-2);border:1px solid var(--border);border-radius:var(--radius-s);padding:6px 12px;font-size:13px;color:var(--teal-deep)}.login-screen{min-height:100dvh;display:flex;align-items:center;justify-content:center;padding:var(--space-4);background:var(--surface-2)}.login-card{background:var(--surface);border-radius:var(--radius-l);box-shadow:var(--shadow-2);padding:var(--space-6) var(--space-5);width:100%;max-width:400px;display:flex;flex-direction:column;gap:var(--space-4)}.login-brand{display:flex;flex-direction:column;align-items:center;gap:var(--space-2)}.login-tagline{color:var(--text-2);font-size:13px}.login-form{display:flex;flex-direction:column;gap:var(--space-3)}.login-message{text-align:center;font-size:13px;color:var(--teal-deep)}.field{display:flex;flex-direction:column;gap:6px;font-size:13px;color:var(--text-2)}.field input,.input{font-family:var(--font-ui);font-size:16px;padding:10px 12px;border:1px solid var(--border);border-radius:var(--radius-s);background:var(--surface-2);color:var(--text);width:100%}.field input:focus,.input:focus{outline:2px solid var(--sky-strong);border-color:transparent}.textarea{resize:vertical}.btn-block{width:100%}.btn-small{padding:4px 10px;font-size:12px}.join-row{display:flex;gap:var(--space-2)}.join-row .input{flex:1}.course-list{display:flex;flex-direction:column;gap:var(--space-3)}.course-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-4);display:flex;flex-direction:column;gap:var(--space-3)}.course-head{display:flex;justify-content:space-between;align-items:flex-start;gap:var(--space-2)}.course-name{font-size:17px;font-weight:600}.course-grade{font-size:12px;color:var(--text-2);margin-top:2px}.invite-pill{font-size:12px;border-radius:999px;padding:3px 10px;background:var(--surface-2);border:1px solid var(--border);color:var(--text-2);white-space:nowrap}.invite-pill.on{background:#e5f5f0;border-color:#bee5da;color:var(--teal-deep)}.course-invite{display:flex;align-items:center;gap:var(--space-2);font-size:14px;color:var(--text-2)}.invite-code{font-size:20px;font-weight:700;letter-spacing:4px;color:var(--teal-deep);background:var(--sky);border-radius:var(--radius-s);padding:4px 12px}.course-actions{display:flex;gap:var(--space-2);flex-wrap:wrap}.qr-wrap{display:flex;flex-direction:column;align-items:center;gap:var(--space-2);padding:var(--space-3) 0}.role-badge{font-size:12px;background:var(--sky);color:var(--teal-deep);border-radius:999px;padding:3px 12px;font-weight:600}.member-row{align-items:center}.member-row .btn{margin-left:auto}.file-btn{display:inline-flex;align-items:center;justify-content:center}.import-errors{margin-bottom:var(--space-2)}.import-error-line{font-size:12px;color:var(--danger)}.import-ok{color:var(--success)}.import-fail{color:var(--danger)}.back-btn{align-self:flex-start;margin-bottom:var(--space-2);padding-left:0}.section-title{font-size:17px;color:var(--text);font-weight:600;margin-bottom:var(--space-3);padding-left:10px;border-left:3px solid var(--teal);line-height:1.3}.unit-section{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-3) var(--space-3) var(--space-2);margin-bottom:var(--space-4)}.unit-head{display:flex;align-items:center;gap:var(--space-2);width:100%;border:none;background:transparent;font-family:var(--font-ui);padding:var(--space-2) var(--space-1);cursor:pointer;text-align:left}.unit-head.static{cursor:default;flex-wrap:wrap}.unit-chevron{color:var(--teal);font-size:14px;transition:transform var(--tap-duration) ease}.unit-chevron.open{transform:rotate(90deg)}.unit-name{font-size:17px;font-weight:600;color:var(--text);flex:1}.unit-count{font-size:12px;color:var(--teal-deep);background:var(--sky);border-radius:999px;padding:2px 10px;font-weight:600}.unit-tools{display:flex;gap:2px;align-items:center}.unit-section .course-list{padding:var(--space-1) 0 var(--space-2)}.unit-res-row{display:flex;align-items:center;gap:var(--space-2);padding:var(--space-2) var(--space-1);border-top:1px solid var(--border);font-size:14px}.unit-res-name{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.unit-select{max-width:130px;font-size:13px;padding:6px 8px}.danger-text{color:var(--danger)}.res-badge{display:inline-block;font-size:11px;font-weight:600;border-radius:4px;padding:1px 6px;margin-bottom:4px;letter-spacing:.04em}.res-vocab_list{background:var(--sky);color:var(--teal-deep)}.res-reading{background:#fdf3dc;color:#9a7b1e}.res-exam{background:#fbeaea;color:var(--danger)}.res-scenario{background:#eaf7ef;color:var(--success)}.res-material{background:var(--surface-2);color:var(--text-2);border:1px solid var(--border)}.course-sticky-head{position:sticky;top:0;z-index:5;background:var(--surface-2);margin:calc(-1 * var(--space-4)) calc(-1 * var(--space-4)) var(--space-3);padding:var(--space-2) var(--space-4) var(--space-2);border-bottom:1px solid var(--border)}.material-row .res-badge{margin-bottom:0}.sort-row{display:flex;gap:var(--space-2);margin-bottom:var(--space-3);align-items:center}.sort-label{font-size:12px;color:var(--text-2)}.filter-row{display:flex;gap:var(--space-2);margin-bottom:var(--space-3)}.select{max-width:140px}.tappable{cursor:pointer;transition:transform var(--tap-duration) ease,box-shadow var(--tap-duration) ease}.tappable:active{transform:scale(var(--tap-scale));box-shadow:var(--shadow-1)}.chip-row{display:flex;flex-wrap:wrap;gap:var(--space-2)}.chip{font-family:var(--font-ui);font-size:13px;border:1px solid var(--border);border-radius:999px;padding:6px 14px;background:var(--surface);color:var(--text-2);cursor:pointer;transition:transform var(--tap-duration) ease,background var(--tap-duration) ease,color var(--tap-duration) ease}.chip:active{transform:scale(var(--tap-scale))}.chip.on{background:var(--teal);border-color:var(--teal);color:#fff;font-weight:600}.vocab-table{display:flex;flex-direction:column;gap:var(--space-2)}.vocab-row{position:relative;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-s);padding:var(--space-3) var(--space-4)}.vocab-main{display:flex;gap:var(--space-2);align-items:baseline;flex-wrap:wrap;padding-right:56px}.vocab-term{font-weight:600;font-size:16px}.vocab-pos{font-size:12px;color:var(--text-2);font-style:italic}.vocab-translation{font-size:14px;color:var(--text-2)}.vocab-example{font-size:13px;color:var(--text-2);margin-top:4px;padding-right:56px}.vocab-delete{position:absolute;top:8px;right:8px}.offline-note{font-size:13px;color:#8a6d1a;background:#fdf6e3;border:1px solid #F0E1B9;border-radius:var(--radius-s);padding:8px 12px;margin-bottom:var(--space-3)}.player-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:var(--surface-2);z-index:90;overflow-y:auto}.player{max-width:480px;margin:0 auto;padding:calc(env(safe-area-inset-top) + var(--space-4)) var(--space-4) calc(env(safe-area-inset-bottom) + var(--space-5));display:flex;flex-direction:column;gap:var(--space-3);min-height:100dvh}.player-head{display:flex;justify-content:space-between;align-items:center}.player-title{font-size:16px}.player-controls{display:flex;gap:var(--space-2);flex-wrap:wrap}.player-progress{text-align:center;font-size:13px;color:var(--text-2);font-variant-numeric:tabular-nums}.flashcard{perspective:1200px;cursor:pointer;flex:1;min-height:300px;display:flex}.flashcard-inner{position:relative;width:100%;transform-style:preserve-3d;transition:transform .32s cubic-bezier(.4,.2,.2,1)}.flashcard.flipped .flashcard-inner{transform:rotateY(180deg)}.flashcard-face{position:absolute;top:0;right:0;bottom:0;left:0;backface-visibility:hidden;-webkit-backface-visibility:hidden;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-l);box-shadow:var(--shadow-2);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:var(--space-3);padding:var(--space-5);text-align:center}.flashcard-back{transform:rotateY(180deg);background:var(--sky)}.flash-term{font-size:32px;font-weight:700;color:var(--ink);word-break:break-word}.flash-phonetic{font-size:16px;color:var(--text-2)}.flash-pos{font-size:14px;color:var(--teal-deep);font-style:italic}.flash-example{font-size:15px;color:var(--text-2);line-height:1.6}.flash-hint{position:absolute;bottom:16px;font-size:12px;color:var(--text-2);opacity:.7}.player-mark{display:flex;gap:var(--space-3)}.btn-mark{flex:1;font-size:17px;font-weight:600;padding:14px 0;border-radius:var(--radius-m)}.btn-again{background:#fdf0ec;color:var(--coral)}.btn-again:active{background:#fadfd6}.btn-got{background:var(--teal);color:#fff}.btn-got:active{background:var(--teal-deep)}.player-nav{display:flex;justify-content:space-between}.center{text-align:center}.select-full{width:100%}.quiz-prompt{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-l);box-shadow:var(--shadow-1);padding:var(--space-5);text-align:center;display:flex;flex-direction:column;gap:var(--space-2);align-items:center}.quiz-options{display:flex;flex-direction:column;gap:var(--space-2)}.quiz-option{font-family:var(--font-ui);font-size:16px;text-align:left;padding:14px 16px;border:1px solid var(--border);border-radius:var(--radius-m);background:var(--surface);color:var(--text);cursor:pointer;transition:transform var(--tap-duration) ease,background var(--tap-duration) ease,border-color var(--tap-duration) ease,opacity var(--tap-duration) ease}.quiz-option:active{transform:scale(var(--tap-scale))}.quiz-option.correct{background:#e5f5f0;border-color:var(--teal);color:var(--teal-deep);font-weight:600}.quiz-option.wrong{background:#fbeaea;border-color:var(--danger);color:var(--danger)}.quiz-option.dim{opacity:.45}.spelling-input{font-size:20px;text-align:center;letter-spacing:1px}.quiz-verdict{text-align:center;font-size:15px;font-weight:600}.quiz-verdict.ok{color:var(--success)}.quiz-verdict.no{color:var(--danger)}.quiz-result{display:flex;flex-direction:column;gap:var(--space-3)}.quiz-score{font-size:64px;font-weight:700;color:var(--teal-deep);text-align:center;font-variant-numeric:tabular-nums}.quiz-score-unit{font-size:24px;color:var(--text-2);margin-left:4px}.vocab-row.mastered{opacity:.55}.weak-meta{display:flex;gap:var(--space-3);margin-top:4px;font-size:12px;color:var(--text-2);padding-right:88px}.weak-count{color:var(--coral);font-weight:600}.weak-toggle{position:absolute;top:10px;right:10px}.audio-btn{border:1px solid var(--border);background:var(--surface);border-radius:50%;width:34px;height:34px;font-size:15px;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;transition:transform var(--tap-duration) ease,background var(--tap-duration) ease;flex-shrink:0}.audio-btn:active{transform:scale(var(--tap-scale));background:var(--sky)}.audio-btn.big{width:48px;height:48px;font-size:20px}.audio-btn.busy{opacity:.6}.library-seg{padding:var(--space-3) var(--space-4);position:sticky;top:0;z-index:6;background:var(--surface-2);border-bottom:1px solid var(--border)}.reading-body{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-5) var(--space-4);font-size:17px;line-height:2.1;color:var(--text)}.reading-body p{margin-bottom:var(--space-4)}.reading-body p:last-child{margin-bottom:0}.reading-word{cursor:pointer;border-radius:4px;padding:1px;transition:background var(--tap-duration) ease}.reading-word:active{background:var(--sky)}.marked-word{background:#fff3d6;box-shadow:inset 0 -2px 0 var(--sun);font-weight:600}.reading-sentence{cursor:default}.marked-sentence{background:#e5f5f0;box-shadow:inset 0 -2px 0 var(--teal);border-radius:4px}.reading-summary{display:flex;gap:var(--space-4);margin-top:var(--space-3);font-size:14px;color:var(--teal-deep);font-weight:600}.option-row{display:flex;gap:var(--space-2);align-items:center;margin-bottom:var(--space-2)}.option-pick{width:38px;height:38px;border-radius:50%;border:1px solid var(--border);background:var(--surface);color:var(--text-2);font-weight:700;cursor:pointer;flex-shrink:0;transition:transform var(--tap-duration) ease,background var(--tap-duration) ease}.option-pick:active{transform:scale(var(--tap-scale))}.option-pick.on{background:var(--teal);border-color:var(--teal);color:#fff}.qtype-badge{font-size:12px;border-radius:6px;padding:2px 8px;font-weight:600;flex-shrink:0}.qtype-choice{background:#e5f5f0;color:var(--teal-deep)}.qtype-fill{background:#fff3d6;color:#8a6d1a}.qtype-tf{background:#eaf6fc;color:#2b6e8c}.qtype-short{background:#f3ecfa;color:#6b4e9b}.qtype-essay{background:#fdf0ec;color:var(--coral)}.qtype-reading{background:#eff2f4;color:var(--ink)}.q-stem{font-size:14px}.count-row{display:flex;justify-content:space-between;align-items:center;padding:6px 0}.count-stepper{display:flex;align-items:center;gap:var(--space-2)}.count-value{min-width:28px;text-align:center;font-weight:700;font-variant-numeric:tabular-nums}.gen-answer{font-size:13px;color:var(--teal-deep);margin-top:4px}.picked{border-color:var(--teal);background:#f2faf8}.pick-order{width:24px;height:24px;border-radius:50%;background:var(--teal);color:#fff;font-size:12px;font-weight:700;display:inline-flex;align-items:center;justify-content:center;flex-shrink:0}.exam-passage{background:var(--sky);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-4);font-size:15px;line-height:1.9;margin-bottom:var(--space-2);white-space:pre-wrap}.taker-q{padding-bottom:var(--space-4)}.result-row.r-ok{border-left:4px solid var(--success)}.result-row.r-no{border-left:4px solid var(--danger)}.result-lines{margin-top:6px;font-size:13px;color:var(--text-2);display:flex;flex-direction:column;gap:3px}.result-score{color:var(--teal-deep);font-weight:600}.result-feedback{background:var(--surface-2);border-radius:var(--radius-s);padding:8px 10px;line-height:1.7}.dialogue-player{gap:var(--space-2)}.dialogue-scroll{flex:1;overflow-y:auto;display:flex;flex-direction:column;gap:var(--space-2);padding:var(--space-2) 0;min-height:200px}.bubble-row{display:flex}.bubble-row.ai{justify-content:flex-start}.bubble-row.student{justify-content:flex-end}.bubble-row.correction{justify-content:center}.bubble{max-width:82%;padding:10px 14px;border-radius:var(--radius-m);font-size:15px;line-height:1.6}.bubble-ai{background:var(--surface);border:1px solid var(--border);border-bottom-left-radius:4px}.bubble-student{background:var(--teal);color:#fff;border-bottom-right-radius:4px}.bubble-correction{background:#fff3d6;border:1px solid #F0E1B9;color:#8a6d1a;font-size:13px;max-width:92%}.bubble.thinking{color:var(--text-2);letter-spacing:3px}.dialogue-controls{padding-top:var(--space-2)}.mic-btn{width:100%;border:none;border-radius:var(--radius-l);background:var(--teal);color:#fff;padding:16px 0;font-family:var(--font-ui);font-size:16px;font-weight:600;cursor:pointer;display:flex;align-items:center;justify-content:center;gap:var(--space-2);transition:transform var(--tap-duration) ease,background var(--tap-duration) ease;box-shadow:var(--shadow-2)}.mic-btn:active{transform:scale(var(--tap-scale))}.mic-btn:disabled{background:var(--border);color:var(--text-2);box-shadow:none}.mic-btn.recording{background:var(--coral);animation:mic-pulse 1.2s ease-in-out infinite}@keyframes mic-pulse{0%,to{box-shadow:0 0 #f48b6c80}50%{box-shadow:0 0 0 12px #f48b6c00}}.mic-icon{font-size:20px}.dialogue-summary{font-size:14px;line-height:1.9;white-space:pre-wrap}.stat-row{display:flex;gap:var(--space-2);margin-bottom:var(--space-2)}.stat{flex:1;background:var(--surface-2);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-3);display:flex;flex-direction:column;align-items:center;gap:2px}.stat-num{font-size:22px;font-weight:700;color:var(--teal-deep);font-variant-numeric:tabular-nums}.stat-label{font-size:11px;color:var(--text-2);text-align:center}.chart-scroll{overflow-x:auto;padding:var(--space-2) 0}.advice-list{padding-left:20px;display:flex;flex-direction:column;gap:var(--space-2);font-size:14px;line-height:1.8;margin-bottom:var(--space-3)}.flagged{border-left:4px solid var(--coral)}.flag-pill{font-size:11px;background:#fdf0ec;color:var(--coral);border-radius:999px;padding:2px 8px;font-weight:600}@keyframes page-in{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}.page{animation:page-in .24s cubic-bezier(.2,.7,.3,1)}@keyframes pop-ok{0%{transform:scale(1)}40%{transform:scale(1.03)}to{transform:scale(1)}}.quiz-option.correct{animation:pop-ok .28s ease}@keyframes chip-pop{0%{transform:scale(.92)}60%{transform:scale(1.06)}to{transform:scale(1)}}.chip.on{animation:chip-pop .2s ease}.course-card,.vocab-row{transition:box-shadow var(--tap-duration) ease,border-color var(--tap-duration) ease}.file-badge{font-size:11px;font-weight:700;background:var(--sky);color:var(--teal-deep);border-radius:6px;padding:3px 7px;flex-shrink:0}.link-btn{text-align:center;text-decoration:none;display:block}.library-seg .segment{font-size:12.5px;padding:8px 0}.today-panel h2{margin-bottom:10px}.today-row{display:flex;align-items:center;gap:10px;padding:8px 0;border-bottom:1px solid rgba(43,71,80,.08)}.today-row:last-child{border-bottom:none}.today-count{min-width:30px;height:30px;padding:0 6px;display:inline-flex;align-items:center;justify-content:center;border-radius:15px;background:#fff3de;border:1px solid #F4D9A6;color:#8a5a00;font-weight:700;font-variant-numeric:tabular-nums;flex-shrink:0}.today-label{flex:1;min-width:0;color:var(--ink)}.today-hint{color:#2b47508c;font-size:.85em;flex-shrink:0}.today-done{color:var(--teal-deep);padding:4px 0}.course-badge{align-self:flex-start;padding:3px 10px;border-radius:12px;background:#fff3de;border:1px solid #F4D9A6;color:#8a5a00;font-size:.85em;font-weight:600;white-space:nowrap;flex-shrink:0}.btn-badge{display:inline-flex;align-items:center;justify-content:center;min-width:18px;height:18px;padding:0 5px;margin-left:6px;border-radius:9px;background:#e85d4a;color:#fff;font-size:.75em;font-weight:700;font-variant-numeric:tabular-nums;vertical-align:1px}.player-overlay.rotated{inset:auto;top:0;left:100dvw;width:100dvh;height:100dvw;transform:rotate(90deg);transform-origin:left top}.player-overlay.rotated .player{max-width:760px;padding:var(--space-4) max(var(--space-5),env(safe-area-inset-bottom)) var(--space-5) max(var(--space-5),env(safe-area-inset-top))}.player-overlay.rotated .flash-term{font-size:46px}.player-overlay.rotated .flash-phonetic{font-size:20px}.player-overlay.rotated .flash-example{font-size:18px}.player-overlay.rotated .player-progress{font-size:16px}.player-overlay.rotated .quiz-options{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-3)}.player-overlay.rotated .quiz-option{font-size:20px;padding:16px 20px}.player-overlay.rotated .spelling-input{font-size:26px}.player-overlay.rotated .q-stem{font-size:18px;line-height:1.6}.player-overlay.rotated .exam-passage{font-size:17px;line-height:1.7}.player-overlay.rotated .input{font-size:17px}.player-overlay.rotated .quiz-verdict{font-size:18px}.exam-player .player-head span{display:inline-flex;gap:4px}.taker-toolbar{display:flex;align-items:center;justify-content:space-between;gap:var(--space-2);margin-bottom:4px}@media (min-width: 768px){.page{max-width:720px;margin-inline:auto}.page-title{font-size:26px}.btn,.tab-btn{font-size:16px}.segment{font-size:15px}.input,.q-stem{font-size:16px}.quiz-option{font-size:18px}.flash-term{font-size:40px}.flash-example{font-size:17px}.exam-passage{font-size:16px;line-height:1.7}.player{max-width:620px}.vocab-term{font-size:17px}.section-title{font-size:18px}}@media (min-width: 1024px){.page{max-width:860px}.player{max-width:700px}.page-title{font-size:28px}}.digest-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(96px,1fr));gap:var(--space-2);margin-bottom:var(--space-3)}.digest-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-m);padding:10px 8px;display:flex;flex-direction:column;align-items:center;gap:2px}.digest-num{font-size:22px;font-weight:700;color:var(--ink);font-variant-numeric:tabular-nums}.digest-num small{font-size:13px;font-weight:500;color:var(--text-2);margin-left:1px}.digest-num .delta-up{color:var(--success, #2E9E6B);font-size:12px;margin-left:4px}.digest-num .delta-down{color:var(--danger, #C0392B);font-size:12px;margin-left:4px}.digest-label{font-size:12px;color:var(--text-2);text-align:center}.digest-alert{color:#8a5a00;background:#fff3de;border:1px solid #F4D9A6;border-radius:var(--radius-s);padding:8px 10px;margin:6px 0;font-size:14px}.digest-alert.dim{color:var(--text-2);background:var(--surface);border-color:var(--border)}.conv-chip{font-size:12px;padding:2px 8px;border-radius:10px;border:1px solid;white-space:nowrap}.conv-chip.weak{background:#fbeaea;border-color:#eac1bc;color:#a5392c}.conv-chip.mark{background:#fff3de;border-color:#f4d9a6;color:#8a5a00}.conv-chip.ask{background:#e8f1fa;border-color:#bdd7ee;color:#2b5e8c}.dead-chip,.stuck-chip{font-size:12px;padding:2px 8px;border-radius:10px;white-space:nowrap}.dead-chip{background:var(--surface);border:1px dashed var(--border);color:var(--text-2)}.stuck-chip{background:#fbeaea;border:1px solid #EAC1BC;color:#a5392c}.source-picker{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-m);padding:var(--space-3);display:flex;flex-direction:column;gap:var(--space-2);max-height:40dvh;overflow-y:auto}.source-row{display:flex;align-items:center;gap:var(--space-2);padding:8px 10px;border:1px solid var(--border);border-radius:var(--radius-s);background:var(--surface);font-family:var(--font-ui);font-size:14px;text-align:left;cursor:pointer}.source-row .q-stem{flex:1;min-width:0}.source-row.done{opacity:.5;cursor:default}.sheet-sub{color:#555;font-size:12.5px;margin-top:2px}.sheet-comment{margin:8px 0;padding:8px 10px;border-left:3px solid #ccc}.sheet-comment p{margin:4px 0 0;white-space:pre-wrap}.sheet-foot{margin-top:24px;padding-top:8px;border-top:1px solid #ddd;color:#888;font-size:12px;text-align:center}.print-toolbar .player-controls{flex:1;justify-content:center}.diff-badge{font-size:12px;padding:1px 8px;border-radius:10px;border:1px solid;white-space:nowrap;margin-left:6px}.diff-low{background:#e5f5f0;border-color:#bee5da;color:var(--teal-deep)}.diff-mid{background:#fff3de;border-color:#f4d9a6;color:#8a5a00}.diff-high{background:#fbeaea;border-color:#eac1bc;color:#a5392c}