:root{color-scheme:light;--bg:#f8fafc;--surface:#fff;--surface-alt:#f1f5f9;--text:#17212f;--muted:#5b6878;--line:#dce3eb;--primary:#175cd3;--primary-hover:#1249aa;--primary-soft:#e9f0fe;--green:#176642;--green-bg:#e8f6ee;--amber:#8b5700;--amber-bg:#fff5da;--red:#b03131;--red-bg:#fdf0f0;--code:#152236;--code-text:#ecf4ff;--shadow:0 12px 32px rgba(22,35,53,.055)}
:root[data-theme="dark"]{color-scheme:dark;--bg:#0c131c;--surface:#131e2a;--surface-alt:#1b2a38;--text:#e9f0f7;--muted:#a7b4c3;--line:#2b3b4b;--primary:#76aaff;--primary-hover:#9bc1ff;--primary-soft:#1b3556;--green:#86d8ad;--green-bg:#153a2a;--amber:#f4cb73;--amber-bg:#3c3017;--red:#ff9b9b;--red-bg:#42252a;--code:#09111d;--code-text:#e9f0fa;--shadow:0 12px 32px rgba(0,0,0,.12)}
@media(prefers-color-scheme:dark){:root:not([data-theme="light"]):not([data-theme="dark"]){color-scheme:dark;--bg:#0c131c;--surface:#131e2a;--surface-alt:#1b2a38;--text:#e9f0f7;--muted:#a7b4c3;--line:#2b3b4b;--primary:#76aaff;--primary-hover:#9bc1ff;--primary-soft:#1b3556;--green:#86d8ad;--green-bg:#153a2a;--amber:#f4cb73;--amber-bg:#3c3017;--red:#ff9b9b;--red-bg:#42252a;--code:#09111d;--code-text:#e9f0fa;--shadow:0 12px 32px rgba(0,0,0,.12)}}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.65 -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif}button,input,select{font:inherit}button,a{-webkit-tap-highlight-color:transparent}button{cursor:pointer}a{color:var(--primary);text-decoration:none}a:hover{text-decoration:underline}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--primary);outline-offset:3px}[hidden]{display:none!important}.skip-link{position:absolute;left:-9999px;top:8px;background:var(--surface);padding:8px 16px;z-index:100}.skip-link:focus{left:8px}.site-header{position:sticky;top:0;z-index:20;background:var(--surface);border-bottom:1px solid var(--line)}.header-inner{max-width:1200px;min-height:68px;padding:0 24px;margin:auto;display:flex;align-items:center;gap:28px}.brand{display:flex;align-items:center;gap:10px;flex:none;color:var(--text);font-size:15px;font-weight:650;letter-spacing:-.02em}.brand:hover{text-decoration:none}.brand strong{color:var(--primary)}.brand-mark{display:grid;place-items:center;width:34px;height:34px;border-radius:9px;background:var(--primary);color:#fff;font:700 13px ui-monospace,SFMono-Regular,monospace}.desktop-nav{display:flex;align-items:center;gap:4px;margin-left:auto}.desktop-nav a{color:var(--muted);font-size:14px;font-weight:550;padding:8px 11px;border-radius:7px;white-space:nowrap}.desktop-nav a:hover,.desktop-nav a.active{color:var(--primary);background:var(--primary-soft);text-decoration:none}.header-actions{display:flex;gap:5px}.icon-button{border:0;background:transparent;color:var(--muted);display:grid;place-items:center;width:36px;height:36px;border-radius:8px;font-size:21px}.icon-button:hover{background:var(--surface-alt);text-decoration:none;color:var(--text)}.mobile-nav{display:none}.page{max-width:1160px;padding:42px 24px 90px;margin:auto}.page.narrow{max-width:820px}.eyebrow{color:var(--primary);font:700 11px/1.4 ui-monospace,SFMono-Regular,monospace;letter-spacing:.12em;text-transform:uppercase}.hero{padding:58px 58px 54px;border:1px solid var(--line);border-radius:18px;background:var(--surface);box-shadow:var(--shadow)}.hero-title{white-space:pre-line;font-size:clamp(34px,4.4vw,55px);line-height:1.18;letter-spacing:-.045em;margin:15px 0 18px;font-weight:750}.hero-copy{font-size:18px;max-width:650px;color:var(--muted);margin:0 0 30px}.hero-actions,.mistake-actions{display:flex;gap:12px;flex-wrap:wrap}.button{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:10px 18px;border:1px solid var(--line);border-radius:9px;background:var(--surface);color:var(--text);font-weight:650;text-decoration:none;line-height:1.35}.button:hover{text-decoration:none;background:var(--surface-alt)}.button.primary{background:var(--primary);border-color:var(--primary);color:#fff}.button.primary:hover{background:var(--primary-hover);border-color:var(--primary-hover)}.button.subtle{background:var(--surface-alt)}.button.full{width:100%}.button.danger{border-color:var(--red);color:var(--red);background:transparent}.button.danger:hover{background:var(--red-bg)}.text-button{border:0;background:transparent;color:var(--primary);font-weight:650;padding:5px 0}.text-button:hover{text-decoration:underline}.stats-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:12px;margin:22px 0 13px}.stat-card{display:flex;flex-direction:column;padding:22px 24px;background:var(--surface);border:1px solid var(--line);border-radius:12px}.stat-value{font-size:30px;line-height:1.2;letter-spacing:-.03em;font-weight:730;font-variant-numeric:tabular-nums}.stat-label{margin-top:7px;color:var(--muted);font-size:13px}.progress-line{display:flex;align-items:center;gap:16px;color:var(--muted);font-size:13px}.progress-line .progress-bar{flex:1}.progress-bar{height:7px;background:var(--surface-alt);border-radius:99px;overflow:hidden}.progress-bar span{display:block;height:100%;border-radius:inherit;background:var(--primary)}.home-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin-top:36px}.panel{border:1px solid var(--line);background:var(--surface);border-radius:14px;padding:27px}.panel h2{font-size:21px;line-height:1.3;letter-spacing:-.02em;margin:9px 0 9px}.panel p{color:var(--muted);margin:0 0 18px}.featured-panel{background:var(--primary-soft)}.path-link{display:block;padding:11px 0;border-bottom:1px solid var(--line);font-weight:600;color:var(--text)}.path-link:last-child{border:0}.path-link:hover{color:var(--primary);text-decoration:none}.section-heading{margin-bottom:28px}.page-title{font-size:clamp(30px,3vw,41px);letter-spacing:-.04em;line-height:1.2;margin:10px 0}.lead{color:var(--muted);margin:0;max-width:760px}.filter-panel{display:grid;grid-template-columns:2fr repeat(4,1fr);gap:12px;padding:18px;border:1px solid var(--line);border-radius:13px;background:var(--surface)}.field{display:flex;flex-direction:column;gap:6px;font-size:13px;font-weight:600;color:var(--muted);min-width:0}.field input,.field select{width:100%;height:43px;padding:0 12px;border:1px solid var(--line);border-radius:8px;background:var(--bg);color:var(--text);font-size:14px}.field input::placeholder{color:var(--muted)}.result-count{color:var(--muted);font-size:14px;margin:23px 0 10px}.word-list{border:1px solid var(--line);border-radius:12px;background:var(--surface);overflow:hidden}.word-list.spaced{margin-top:24px}.word-row{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:16px 20px;border-bottom:1px solid var(--line);color:var(--text)}.word-row:last-child{border:0}.word-row:hover{text-decoration:none;background:var(--surface-alt)}.word-row>div:first-child{display:flex;flex-direction:column;min-width:0}.word-row strong,.strong-link{font-size:17px;font-weight:700;color:var(--text);overflow-wrap:anywhere}.word-meaning{font-size:14px;color:var(--muted)}.word-meta{display:flex;align-items:center;gap:10px;color:var(--muted);font-size:12px;text-align:right}.level-tag,.status-tag{display:inline-flex;align-items:center;border:1px solid var(--line);border-radius:6px;padding:3px 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10px}.phrase-list,.related-list{display:flex;flex-wrap:wrap;gap:8px}.phrase,.related-link{font-size:13px;border:1px solid var(--line);background:var(--surface-alt);border-radius:7px;padding:5px 10px}.related-link:hover{text-decoration:none;background:var(--primary-soft)}.english-example{font-size:17px;font-weight:550;margin:0 0 4px}.chinese-example,.technical-note{color:var(--muted);margin:0}.code-wrap{border-radius:10px;overflow:hidden;background:var(--code);color:var(--code-text);margin:10px 0 12px}.code-top{display:flex;align-items:center;justify-content:space-between;padding:8px 13px;border-bottom:1px solid rgba(255,255,255,.1);color:#aac0d8;font:12px ui-monospace,SFMono-Regular,monospace}.copy-button{border:0;border-radius:5px;background:rgba(255,255,255,.13);color:var(--code-text);padding:5px 9px;font:12px ui-monospace,SFMono-Regular,monospace}.copy-button:hover{background:rgba(255,255,255,.24)}pre{margin:0;padding:17px;overflow-x:auto;white-space:pre-wrap;overflow-wrap:anywhere;tab-size:2}code{font:13px/1.65 ui-monospace,SFMono-Regular,Consolas,monospace}.small-note{color:var(--muted);font-size:13px}.study-controls{display:flex;align-items:end;justify-content:space-between;gap:16px;margin-bottom:26px}.study-controls .field{width:150px}.study-progress{color:var(--muted);font-size:13px;font-weight:650;margin:0 0 10px}.study-card{margin-top:18px;border:1px solid var(--line);background:var(--surface);border-radius:16px;padding:34px;box-shadow:var(--shadow)}.study-prompt{padding:40px 0 60px;text-align:center}.study-word{font-size:clamp(38px,6vw,60px);line-height:1.15;letter-spacing:-.045em;margin:16px 0 12px;overflow-wrap:anywhere}.study-prompt .pronunciation{justify-content:center}.reveal-button{width:100%}.study-reveal .detail-content{border:0;padding:0;box-shadow:none}.study-reveal .word-top{display:none}.answer-actions{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;border-top:1px solid var(--line);padding-top:19px}.answer-actions .button{min-height:53px}.answer-known{background:var(--green-bg);color:var(--green);border-color:var(--green)}.answer-fuzzy{background:var(--amber-bg);color:var(--amber);border-color:var(--amber)}.answer-unknown{background:var(--red-bg);color:var(--red);border-color:var(--red)}.category-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}.category-card{border:1px solid var(--line);border-radius:12px;background:var(--surface);padding:23px}.category-number{font:700 12px ui-monospace,monospace;color:var(--primary)}.category-card h2{font-size:21px;margin:9px 0 4px}.category-card p{color:var(--muted);margin:0 0 18px}.quiz-modes{display:grid;grid-template-columns:repeat(2,1fr);gap:13px}.quiz-card{border:1px solid var(--line);border-radius:14px;background:var(--surface);padding:26px}.quiz-prompt{font-size:23px;line-height:1.35;white-space:pre-wrap;overflow-wrap:anywhere;margin:0 0 22px}.quiz-choices{display:grid;gap:10px;margin-bottom:16px}.choice-button{text-align:left;border:1px solid var(--line);background:var(--surface-alt);color:var(--text);border-radius:9px;min-height:49px;padding:10px 15px}.choice-button:hover:not(:disabled){border-color:var(--primary);background:var(--primary-soft)}.choice-button.correct{border-color:var(--green);background:var(--green-bg)}.choice-button.wrong{border-color:var(--red);background:var(--red-bg)}.choice-button:disabled{cursor:default}.quiz-feedback{min-height:25px;font-weight:650}.complete-panel{text-align:center;padding:50px 24px}.complete-panel .button{margin:5px}.complete-icon{display:grid;place-items:center;margin:0 auto 12px;width:48px;height:48px;border-radius:50%;background:var(--green-bg);color:var(--green);font-size:25px}.score{font-size:26px!important;font-weight:700;color:var(--text)!important}.empty-state{text-align:center}.mistake-actions{margin-bottom:20px}.error-grid,.confusion-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:13px}.error-card h2{font:700 17px ui-monospace,SFMono-Regular,monospace;overflow-wrap:anywhere}.error-card p{color:var(--text)}.error-meta{display:flex;flex-direction:column;gap:3px;font-size:12px;color:var(--muted)}.confusion-grid .panel h2{overflow-wrap:anywhere}.settings-panel{margin-bottom:15px}.settings-panel .field{max-width:250px}.settings-panel>*+*{margin-top:16px}.import-label{display:flex;flex-direction:column;gap:8px;font-size:14px;font-weight:650}.import-label input{max-width:100%;font-size:13px}.more-links{background:var(--surface);padding:12px 20px;border:1px solid var(--line);border-radius:12px}.modal-overlay{position:fixed;inset:0;z-index:50;background:rgba(5,15,30,.6);display:grid;place-items:center;padding:20px}.onboarding{max-width:440px;width:100%;border-radius:16px;background:var(--surface);padding:34px;box-shadow:0 25px 80px rgba(0,0,0,.22)}.onboarding h2{font-size:30px;line-height:1.2;letter-spacing:-.03em;margin:10px 0}.onboarding p{color:var(--muted);margin:0 0 25px}.toast{position:fixed;bottom:24px;left:50%;transform:translate(-50%,12px);background:var(--text);color:var(--bg);padding:9px 17px;border-radius:8px;font-size:13px;opacity:0;pointer-events:none;transition:opacity .2s,transform .2s;z-index:100}.toast.show{opacity:1;transform:translate(-50%,0)}
@media(max-width:1050px){.desktop-nav a{padding:8px 7px;font-size:13px}.header-inner{gap:14px}.filter-panel{grid-template-columns:repeat(4,1fr)}.filter-panel .wide{grid-column:1/-1}}
@media(max-width:760px){.site-header{position:relative}.header-inner{min-height:58px;padding:0 17px}.desktop-nav{display:none}.header-actions{margin-left:auto}.mobile-nav{display:grid;grid-template-columns:repeat(5,1fr);position:fixed;bottom:0;left:0;right:0;z-index:30;background:var(--surface);border-top:1px solid var(--line);padding-bottom:env(safe-area-inset-bottom)}.mobile-nav a{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:0;min-height:57px;font-size:11px;color:var(--muted)}.mobile-nav a span{font-size:21px;line-height:1.2}.mobile-nav a.active{color:var(--primary);font-weight:700;text-decoration:none}.page{padding:24px 16px calc(88px + env(safe-area-inset-bottom))}.hero{padding:34px 25px}.hero-title{font-size:37px}.hero-copy{font-size:16px}.stats-grid{grid-template-columns:repeat(2,1fr);gap:9px}.stat-card{padding:15px 17px}.stat-value{font-size:27px}.stats-grid .stat-card:last-child{grid-column:1/-1}.home-grid,.category-grid,.quiz-modes,.error-grid,.confusion-grid{grid-template-columns:1fr}.home-grid{margin-top:25px}.filter-panel{grid-template-columns:repeat(2,1fr);gap:10px;padding:12px}.filter-panel .wide{grid-column:1/-1}.word-row{align-items:flex-start;flex-direction:column;gap:8px;padding:13px 15px}.word-meta{flex-wrap:wrap;text-align:left}.detail-content{padding:22px}.study-card{padding:21px}.study-prompt{padding:35px 0 50px}.study-controls{align-items:stretch;flex-direction:column}.study-controls .field{width:100%}.answer-actions{gap:7px}.answer-actions .button{padding:8px 5px;font-size:14px}.toast{bottom:calc(74px + env(safe-area-inset-bottom));max-width:90vw;text-align:center}}
@media(max-width:380px){.brand{font-size:13px}.brand-mark{width:30px;height:30px}.hero-title{font-size:32px}.hero-actions .button{flex:1}.filter-panel{grid-template-columns:1fr}.word-title{font-size:29px}}
.copy-helper{position:fixed;top:-1000px;left:-1000px;width:1px;height:1px;opacity:0}
.stat-card-link{color:var(--text)}
.stat-card-link:hover{color:var(--text);background:var(--primary-soft);border-color:var(--primary);text-decoration:none}
.study-prompt{padding:10px 0 20px}
.study-word{margin:10px 0 8px}
.study-answer-actions{border-top:0;border-bottom:1px solid var(--line);padding:0 0 22px;margin-bottom:12px}
.study-answer-actions .button{min-height:66px;font-size:20px;font-weight:750}
.study-schedule{margin:0 0 23px;color:var(--muted);font-size:13px;text-align:center}
.study-reveal .detail-content{margin-bottom:0}
.study-prompt .pronunciation{flex-wrap:wrap;column-gap:12px;row-gap:2px}
.study-inline-meaning{font-size:14px;color:var(--text);font-weight:650}
.study-reveal .meaning{display:none}
.keyboard-hint{font-size:12px;color:var(--muted)}
.review-note{color:var(--muted);font-size:14px;margin:0 0 12px}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.page.study-page{padding-top:22px}
.study-topline{display:flex;justify-content:space-between;align-items:center;color:var(--muted);font-size:13px;font-weight:650;margin-bottom:8px}
.study-options{margin-top:18px;border:1px solid var(--line);border-radius:10px;background:var(--surface);padding:12px 16px}
.study-options summary{cursor:pointer;color:var(--muted);font-size:14px;font-weight:650}
.study-options .study-controls{margin:15px 0 2px}
@media(max-width:760px){.study-prompt{padding:8px 0 17px}.study-answer-actions{gap:7px}.study-answer-actions .button{min-height:58px;font-size:16px;padding:8px 4px}.study-schedule{font-size:11px}}
@media(max-width:760px){.page.study-page{padding-top:12px}}