:root{font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:#172b35;background:#edf3f5;--navy:#173b4b;--ink:#172b35;--muted:#60717a;--teal:#2e7f79;--coral:#e77d68;--cream:#fffaf0;--paper:#fff;--line:#d6e0e4;--soft:#f4f8f9;--gold:#eab45b;--danger:#a33838}*{box-sizing:border-box}body{margin:0;min-width:320px;min-height:100vh;background:linear-gradient(180deg,#eaf3f5,#f8f7f2 55%,#edf3f5)}button,select{font:inherit}.topbar{height:70px;display:grid;grid-template-columns:48px 1fr 48px;gap:12px;align-items:center;padding:0 clamp(14px,3vw,32px);background:rgba(255,255,255,.92);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20;backdrop-filter:blur(12px)}.brand-block{text-align:center}.kicker{font-size:10px;font-weight:800;letter-spacing:.16em;color:var(--teal)}.lesson-title{font-family:Georgia,serif;font-size:20px;margin-top:2px}.icon-button{width:40px;height:40px;border-radius:12px;border:1px solid var(--line);background:white;color:var(--ink);font-size:22px;cursor:pointer}.lesson-main{max-width:1180px;margin:0 auto;padding:22px clamp(12px,3vw,30px) 48px;display:grid;gap:16px}.stage-card,.nav-card{background:white;border:1px solid var(--line);border-radius:22px;box-shadow:0 12px 34px rgba(27,57,69,.08);overflow:hidden}.scene-wrap{position:relative;aspect-ratio:16/9;background:#d9e3e7;overflow:hidden}.scene-image{width:100%;height:100%;object-fit:cover;display:block}.scene-shade{position:absolute;inset:0;background:linear-gradient(180deg,rgba(4,23,31,0) 44%,rgba(4,23,31,.62) 100%);pointer-events:none}.word-overlay{position:absolute;left:clamp(18px,5vw,60px);bottom:clamp(22px,5vw,54px);right:clamp(18px,5vw,60px);color:white;text-shadow:0 2px 12px rgba(0,0,0,.55)}.english-target{font-family:Georgia,serif;font-size:clamp(32px,5vw,64px);line-height:1;font-weight:600}.chinese-gloss{font-size:clamp(18px,2.3vw,28px);font-weight:700;margin-top:10px}.usage-pattern{display:inline-block;margin-top:12px;padding:7px 11px;border-radius:999px;background:rgba(18,44,54,.72);font-size:clamp(13px,1.5vw,17px)}.recap-overlay,.review-overlay{position:absolute;inset:auto clamp(16px,3vw,36px) clamp(18px,3vw,34px);display:flex;gap:8px;flex-wrap:wrap;align-items:flex-end}.recap-chip{background:rgba(255,255,255,.93);border:1px solid rgba(255,255,255,.8);color:var(--ink);border-radius:999px;padding:8px 12px;font-weight:750;font-size:clamp(12px,1.3vw,16px)}.review-overlay{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));align-items:stretch}.review-group{background:rgba(255,255,255,.93);border-radius:15px;padding:10px}.review-group strong{display:block;color:var(--teal);font-size:12px;margin-bottom:6px}.review-group span{display:block;font-size:11px;line-height:1.35}.caption-box{min-height:66px;padding:14px clamp(18px,3vw,34px);display:grid;place-items:center;text-align:center;background:#122c37;color:white;font-size:clamp(15px,1.7vw,20px);line-height:1.42}.media-row{padding:14px clamp(16px,3vw,28px);display:flex;align-items:center;gap:10px;border-top:1px solid #264752;background:#173b4b}.primary-button,.secondary-button,.quiet-button,.danger-button{border:0;border-radius:11px;padding:10px 15px;font-weight:800;cursor:pointer}.primary-button{background:#fff;color:var(--navy)}.secondary-button{background:#e6f4f0;color:#165d57}.quiet-button{background:white;border:1px solid var(--line);color:var(--ink)}.danger-button{background:#fbe5e5;color:var(--danger)}.time-block{margin-left:auto;color:#d7e4e8;font-size:12px;display:flex;gap:12px}.nav-card{padding:14px 18px}.progress-row{display:grid;gap:9px}.progress-copy{display:flex;align-items:center;gap:10px;color:var(--muted);font-size:12px}.mode-pill{font-weight:800;color:#155e5a;background:#dcf0ec;border-radius:999px;padding:4px 8px}.mode-pill.review{color:#7c5b19;background:#fff0c9}.progress-track{height:6px;border-radius:999px;background:#e5ecef;overflow:hidden}.progress-bar{height:100%;width:0;background:linear-gradient(90deg,var(--teal),#61b59b);transition:width .25s}.nav-actions{display:flex;gap:8px;margin-top:12px}.nav-actions #nextBtn{margin-left:auto}.contents-panel{position:fixed;left:0;top:0;bottom:0;width:min(420px,92vw);z-index:50;background:white;box-shadow:18px 0 50px rgba(10,30,40,.18);transform:translateX(-105%);transition:transform .2s;padding:20px;overflow:auto}.contents-panel.open{transform:none}.drawer-scrim{position:fixed;inset:0;background:rgba(5,22,28,.4);z-index:40}.contents-head{display:flex;justify-content:space-between;align-items:start}.contents-head h2{font-family:Georgia,serif;margin:4px 0 14px}.contents-list{display:grid;gap:5px}.contents-item{display:grid;grid-template-columns:28px 1fr auto;gap:8px;align-items:center;text-align:left;width:100%;border:1px solid transparent;background:#f7fafb;border-radius:10px;padding:9px;color:var(--ink);cursor:pointer}.contents-item.active{border-color:#6eb2a9;background:#edf8f5}.contents-item.latest::after{content:'LATEST';font-size:9px;font-weight:900;color:#fff;background:var(--teal);padding:3px 5px;border-radius:999px}.contents-num{font-size:10px;color:var(--muted);font-weight:800}.contents-name{font-size:13px}.practice-panel{padding:18px clamp(16px,3vw,28px);background:#f8fbfb;border-top:1px solid var(--line)}.practice-head{display:flex;justify-content:space-between;gap:16px;align-items:start}.practice-head h3{font-family:Georgia,serif;font-size:25px;margin:3px 0}.practice-head p{margin:4px 0;color:var(--muted);font-size:13px}.practice-scenes{display:flex;gap:8px;overflow:auto;padding:9px 0 13px}.practice-thumb{width:150px;aspect-ratio:16/9;object-fit:cover;border-radius:9px;border:1px solid var(--line);flex:none}.question-card{background:white;border:1px solid var(--line);border-radius:13px;padding:13px;margin:8px 0}.question-card label{font-weight:750;display:block;margin-bottom:8px}.choice-grid{display:flex;flex-wrap:wrap;gap:7px}.choice{border:1px solid var(--line);background:white;color:var(--ink);border-radius:999px;padding:7px 10px;cursor:pointer}.choice.selected{background:#dff2ed;border-color:#6eb2a9}.choice.locked{cursor:default}.practice-feedback{font-size:13px;color:var(--teal);font-weight:750;margin-top:8px}.practice-next{margin-top:12px}.mapping-row{display:grid;grid-template-columns:minmax(160px,1fr) minmax(160px,1fr);gap:8px;align-items:center;margin:8px 0}.mapping-row select{padding:9px;border-radius:9px;border:1px solid var(--line);background:white}.info-dialog{max-width:520px;border:0;border-radius:20px;padding:28px;box-shadow:0 24px 70px rgba(0,0,0,.25)}.info-dialog::backdrop{background:rgba(5,22,28,.48)}.info-dialog h2{font-family:Georgia,serif}.dialog-close{float:right;border:0;background:none;font-size:24px}.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%);background:#173b4b;color:white;padding:10px 14px;border-radius:10px;z-index:80;font-size:13px;box-shadow:0 10px 28px rgba(0,0,0,.2)}
@media(max-width:760px){.lesson-main{padding-left:8px;padding-right:8px}.stage-card,.nav-card{border-radius:15px}.review-overlay{grid-template-columns:repeat(2,minmax(0,1fr));max-height:65%;overflow:auto}.media-row{flex-wrap:wrap}.time-block{width:100%;margin-left:0}.nav-actions{display:grid;grid-template-columns:1fr 1fr}.nav-actions #latestBtn{grid-column:1/-1}.mapping-row{grid-template-columns:1fr}.english-target{font-size:clamp(28px,8vw,48px)}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}