:root{--navy:#173b57;--ink:#153247;--cream:#fff9ea;--paper:#fffdf7;--yellow:#ffd34e;--orange:#ff7657;--mint:#85d8bd;--blue:#6fbde2;--line:#d9e5e6;--muted:#647985;--shadow:0 18px 50px rgba(23,59,87,.13);font-family:"Avenir Next","Trebuchet MS",-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:#f4f8f5}
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.5s}.route-boat{position:absolute;top:50%;left:0;transform:translate(-50%,-50%) rotate(-8deg);display:grid;place-items:center;width:38px;height:38px;background:var(--yellow);border:3px solid var(--paper);border-radius:50%;color:var(--navy);transition:left .5s}.route-stops{display:grid;grid-template-columns:repeat(9,1fr);gap:4px}.route-stops span{text-align:center;font-size:10px;color:var(--muted);font-weight:800}.route-card p{margin:24px 0 0;color:var(--muted);line-height:1.6}.control-deck{margin:26px clamp(16px,3vw,48px) 18px;display:flex;justify-content:space-between;gap:20px;align-items:center}.unit-tabs{display:flex;gap:8px;overflow:auto;padding:4px}.unit-tab,.mode-button{border:0;background:transparent;cursor:pointer;white-space:nowrap;font-weight:800}.unit-tab{padding:10px 14px;border-radius:12px;color:var(--muted)}.unit-tab.active{background:var(--navy);color:white}.mode-switch{display:flex;background:white;border:1px solid var(--line);padding:5px;border-radius:15px;box-shadow:0 6px 20px rgba(23,59,87,.06)}.mode-button{padding:9px 14px;border-radius:10px;color:var(--muted)}.mode-button.active{background:var(--yellow);color:var(--navy)}.view{display:none}.view.active{display:grid}.learning-layout{grid-template-columns:280px minmax(0,1fr);gap:24px;margin:0 clamp(16px,3vw,48px) 50px}.session-panel{background:white;border:1px solid var(--line);border-radius:24px 24px 8px 24px;padding:26px;display:flex;flex-direction:column;gap:26px}.panel-label{color:var(--orange)}.session-panel h2,.list-toolbar h2,.quiz-header h2{font:800 30px/1.15 Georgia,"Songti SC",serif;margin:8px 0}.session-panel p{color:var(--muted)}.session-stats{display:grid;grid-template-columns:1fr 1fr;gap:10px}.session-stats div{background:var(--cream);padding:16px;border-radius:15px}.session-stats strong,.session-stats span{display:block}.session-stats strong{font-size:28px}.session-stats 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28px;display:flex;flex-direction:column;align-items:center}.card-counter{width:min(100%,650px);display:flex;justify-content:space-between;align-items:center;color:var(--muted);font-weight:800}.card-counter div{display:flex;gap:8px}.card-counter button{border:0;background:rgba(255,255,255,.75);padding:8px 12px;border-radius:10px;cursor:pointer}.flashcard{width:min(100%,650px);height:390px;margin:16px auto 18px;position:relative;transform-style:preserve-3d;transition:transform .5s;cursor:pointer}.flashcard.flipped{transform:rotateY(180deg)}.card-face{position:absolute;inset:0;backface-visibility:hidden;background:var(--paper);border-radius:34px 34px 10px 34px;box-shadow:var(--shadow);display:flex;flex-direction:column;align-items:center;justify-content:center;padding:38px;text-align:center;border:1px solid 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30px;padding:clamp(24px,5vw,56px);text-align:center;box-shadow:var(--shadow)}.quiz-card>p{color:var(--muted)}.quiz-word{border:0;background:transparent;display:flex;flex-direction:column;margin:20px auto 36px;cursor:pointer}.quiz-word span{font:800 clamp(38px,6vw,64px)/1.1 Georgia,serif}.quiz-word small{color:var(--orange);margin-top:8px}.answer-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.answer-button{min-height:80px;border:2px solid var(--line);background:var(--paper);border-radius:16px;padding:12px;cursor:pointer;font-weight:800}.answer-button:hover{border-color:var(--blue)}.answer-button.correct{background:#d8f4e7;border-color:#54b98e}.answer-button.wrong{background:#ffe1dc;border-color:var(--orange)}.quiz-feedback{min-height:48px;padding:15px;font-weight:800}.quiz-next{display:none;margin:auto}.quiz-next.show{display:block}.list-view.active{display:block}.search-box{display:flex;align-items:center;gap:10px;background:white;border:1px solid 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@media(max-width:900px){.hero{grid-template-columns:1fr}.learning-layout{grid-template-columns:1fr}.session-panel{display:grid;grid-template-columns:1fr 1fr;align-items:center}.session-panel .shuffle-button{margin:0}.control-deck{align-items:stretch;flex-direction:column}.word-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:620px){.topbar{height:74px}.brand small,.icon-button{display:none}.hero{border-radius:26px 26px 8px 26px;padding:28px 22px}.hero h1{font-size:42px}.hero-actions>*{width:100%}.route-card{padding:20px}.control-deck{margin-top:14px}.mode-switch>*{flex:1}.mode-button{font-size:13px;padding:9px 7px}.learning-layout{gap:12px}.session-panel{grid-template-columns:1fr 1fr;padding:18px;gap:14px}.session-panel>div:first-child,.toggle-row{grid-column:1/-1}.flashcard-stage{padding:14px 12px 22px}.flashcard{height:360px}.card-face{padding:26px 18px}.card-actions{grid-template-columns:1fr 1fr}.master-button{grid-column:1/-1;grid-row:1}.keyboard-tip{display:none}.answer-grid{grid-template-columns:1fr}.quiz-header,.list-toolbar{align-items:stretch;flex-direction:column;gap:12px}.search-box input{min-width:0;width:100%}.word-grid{grid-template-columns:1fr}.route-stops span{font-size:8px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}