:root{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light;--font-ui:ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Heiti SC", "Noto Sans SC", "Microsoft YaHei UI", "Microsoft YaHei", "Segoe UI Variable", "Segoe UI", "Helvetica Neue", Arial, sans-serif;--font-zh:"PingFang SC", "Hiragino Sans GB", "Heiti SC", "Noto Sans SC", "Microsoft YaHei UI", "Microsoft YaHei", ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI Variable", "Segoe UI", "Helvetica Neue", Arial, sans-serif;--font-mono:ui-monospace, SFMono-Regular, "SF Mono", Consolas, "Liberation Mono", monospace;--color-canvas:#f5f6f8;--color-surface:#fff;--color-surface-muted:#eef0f4;--color-text:#111318;--color-text-muted:#5c6370;--color-border:#e2e5eb;--color-accent:#2553e8;--color-accent-strong:#1a3fd1;--color-accent-text:#fff;--color-accent-soft:#e8edff;--color-mark:#e8edff;--color-mark-text:#1a2a8a;--color-focus:#2553e8;--color-warning:#8a5a00;--color-warning-surface:#fff6d8;--color-error:#c0352b;--color-error-surface:#fff1ef;--color-success:#0f7a5a;--shadow-soft:0 1px 2px #1113180a, 0 8px 24px #1113180a;--shadow-sticky:0 -.75rem 2rem #0c0e1214;--radius-small:.5rem;--radius-medium:.75rem;--space-1:.25rem;--space-2:.5rem;--space-3:.75rem;--space-4:1rem;--space-5:1.5rem;--space-6:2rem;--space-7:3rem;--content-width:44rem;--app-header-offset:calc(3.5rem + env(safe-area-inset-top,0px))}:root[data-theme=dark]{--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--color-canvas:#0c0e12;--color-surface:#161920;--color-surface-muted:#1e222b;--color-text:#f1f3f7;--color-text-muted:#9aa3b2;--color-border:#2c313c;--color-accent:#7b93ff;--color-accent-strong:#9aafff;--color-accent-text:#0c0e12;--color-accent-soft:#1c2748;--color-mark:#24306e;--color-mark-text:#dce4ff;--color-focus:#7b93ff;--color-warning:#e8c36a;--color-warning-surface:#2e2614;--color-error:#ffb4ab;--color-error-surface:#3a1e1c;--color-success:#5ec49a;--shadow-soft:0 1px 2px #0000005c, 0 10px 28px #00000047;--shadow-sticky:0 -.75rem 2rem #00000061}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--lightningcss-light: ;--lightningcss-dark:initial;color-scheme:dark;--color-canvas:#0c0e12;--color-surface:#161920;--color-surface-muted:#1e222b;--color-text:#f1f3f7;--color-text-muted:#9aa3b2;--color-border:#2c313c;--color-accent:#7b93ff;--color-accent-strong:#9aafff;--color-accent-text:#0c0e12;--color-accent-soft:#1c2748;--color-mark:#24306e;--color-mark-text:#dce4ff;--color-focus:#7b93ff;--color-warning:#e8c36a;--color-warning-surface:#2e2614;--color-error:#ffb4ab;--color-error-surface:#3a1e1c;--color-success:#5ec49a;--shadow-soft:0 1px 2px #0000005c, 0 10px 28px #00000047;--shadow-sticky:0 -.75rem 2rem #00000061}}*,:before,:after{box-sizing:border-box}html{background:var(--color-canvas);-webkit-text-size-adjust:100%;-moz-text-size-adjust:100%;text-size-adjust:100%;min-width:320px;overflow-x:clip}body{min-width:320px;min-height:100vh;background:var(--color-canvas);min-height:100dvh;color:var(--color-text);font-family:var(--font-ui);font-synthesis:none;-webkit-font-smoothing:antialiased;margin:0;font-size:1rem;line-height:1.5;overflow-x:clip}:lang(zh),:lang(zh-CN),[lang=zh-CN]{font-family:var(--font-zh)}h1:lang(zh),h2:lang(zh),:lang(zh) h1,:lang(zh) h2{font-weight:600}button,input,select,textarea{color:inherit;font:inherit}button,a{-webkit-tap-highlight-color:transparent}a{color:var(--color-accent);text-underline-offset:.18em}a:hover{color:var(--color-accent-strong)}:focus-visible{outline:2px solid 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var(--color-border);background:var(--color-canvas);align-items:center;margin-inline:auto;display:flex;position:sticky;top:0}.wordmark{color:var(--color-text);letter-spacing:-.04em;font-size:1rem;font-weight:700;text-decoration:none}.wordmark:hover{color:var(--color-text)}.app-nav{align-items:center;gap:var(--space-1);margin-left:auto;font-size:.875rem;font-weight:600;display:flex}.app-nav a{min-height:2.75rem;padding-inline:var(--space-3);border-radius:var(--radius-small);color:var(--color-text-muted);align-items:center;text-decoration:none;display:inline-flex}.app-nav a:hover{color:var(--color-text);background:var(--color-surface-muted)}.app-status-notice{width:min(100% - 2rem, var(--content-width));margin:var(--space-3) auto 0;padding:var(--space-3) var(--space-4);border:1px solid var(--color-warning);border-radius:var(--radius-small);background:var(--color-warning-surface);color:var(--color-warning);font-size:.9rem}.pwa-update-notice{justify-content:space-between;align-items:center;gap:var(--space-4);padding:var(--space-3) clamp(var(--space-4), 5vw, var(--space-7));border-bottom:1px solid var(--color-border);background:var(--color-surface);display:flex}.pwa-update-notice p{margin:0}.pwa-update-notice .button{flex:none}.app-main{width:min(100% - 2rem, var(--content-width));padding-block:var(--space-6) calc(var(--space-7) + env(safe-area-inset-bottom));margin-inline:auto}.eyebrow{color:var(--color-text-muted);letter-spacing:.04em;text-transform:uppercase;font-size:.72rem;font-weight:600}.muted-copy{color:var(--color-text-muted)}.panel,.module-card,.queue-card,.context-card,.progress-grid{border:1px solid var(--color-border);border-radius:var(--radius-medium);background:var(--color-surface)}.panel{padding:clamp(var(--space-5), 5vw, 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var(--space-5));border:1px solid var(--color-border);border-radius:var(--radius-medium);background:var(--color-surface);box-shadow:var(--shadow-soft);display:grid}.lexicon-search__bar{align-items:center;gap:var(--space-3);border:1px solid var(--color-border);background:var(--color-canvas);border-radius:999px;min-height:3.75rem;padding:.7rem 1.25rem;display:flex}.lexicon-search__icon{color:var(--color-text-muted);display:inline-flex}.lexicon-search__icon svg{width:1.35rem;height:1.35rem}.lexicon-search__bar input{width:100%;min-width:0;color:var(--color-text);background:0 0;border:0;padding:0;font-size:1.125rem;font-weight:500;line-height:1.4}.lexicon-search__bar input::placeholder{color:var(--color-text-muted);font-weight:500}.lexicon-search__bar input:focus{outline:none}.lexicon-search__bar:focus-within{outline:2px solid var(--color-focus);outline-offset:2px}.lexicon-search__bar input[type=search]::-webkit-search-decoration{appearance:none}.lexicon-search__bar input[type=search]::-webkit-search-cancel-button{appearance:none}.lexicon-search__empty,.lexicon-search__results{padding:var(--space-4) 0 0;border:0;border-top:1px solid var(--color-border);box-shadow:none;background:0 0;border-radius:0;margin:0}.lexicon-search__empty{padding-top:var(--space-4);color:var(--color-text-muted);font-size:.95rem}.lexicon-search__results{gap:var(--space-3);overscroll-behavior:contain;scrollbar-gutter:stable;max-height:min(20rem,48vh);list-style:none;display:grid;overflow:hidden auto}.lexicon-search__results:focus{outline:none}.lexicon-search__results:focus-visible{outline:2px solid var(--color-focus);outline-offset:2px}.lexicon-search__results li{gap:.2rem;display:grid}.lexicon-search__results li+li{padding-top:var(--space-3);border-top:1px solid var(--color-border)}.lexicon-search__meta{gap:var(--space-2);color:var(--color-text-muted);letter-spacing:.04em;text-transform:uppercase;flex-wrap:wrap;font-size:.68rem;font-weight:600;display:flex}.lexicon-search__lemma-row{flex-wrap:wrap;align-items:baseline;gap:.2rem .7rem;display:flex}.lexicon-search__lemma{color:var(--color-text);letter-spacing:-.03em;font-size:1.15rem;font-weight:700}.lexicon-search__gloss{color:var(--color-text-muted);font-size:.95rem;font-weight:500}.lexicon-search__meaning{color:var(--color-text);font-size:.95rem}.lexicon-search__sentence{color:var(--color-text-muted);font-size:.8rem;line-height:1.45}.next-session{gap:var(--space-4);padding:clamp(var(--space-5), 5vw, var(--space-6));border:1px solid 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var(--color-border);background:var(--color-surface);position:sticky}.card-meta{gap:var(--space-2);color:var(--color-text-muted);flex-wrap:wrap;align-items:center;font-size:.8125rem;display:flex}.context-card__pronunciation{margin-top:var(--space-2);color:var(--color-text);letter-spacing:.01em;font-size:clamp(.98rem,3.1vw,1.12rem);font-weight:550;line-height:1.35}.context-card__part-of-speech{color:var(--color-text-muted);font-size:.92em;font-weight:500}.ipa-speak-block{justify-items:start;gap:var(--space-1);display:grid}.ipa-speak{cursor:pointer;text-align:left;background:0 0;border:0;border-radius:.35rem;min-height:2.25rem;margin:0;padding:.15rem .2rem .15rem 0}.ipa-speak:hover,.ipa-speak:focus-visible{color:var(--color-text)}.ipa-speak__mark{color:var(--color-text-muted);display:inline-flex}.ipa-speak:hover .ipa-speak__mark,.ipa-speak:focus-visible .ipa-speak__mark{color:var(--color-accent)}.ipa-speak__error{color:var(--color-error);font-size:.75rem;font-weight:500}.context-lemma{margin:0 0 var(--space-4);letter-spacing:-.04em;overflow-wrap:break-word;font-family:inherit;font-size:clamp(1.85rem,6.2vw,2.55rem);font-weight:750;line-height:1.15}.context-sentence{letter-spacing:-.025em;overflow-wrap:break-word;font-size:clamp(1.35rem,4.4vw,1.85rem);font-weight:500;line-height:1.45}mark{background:var(--color-mark);color:var(--color-mark-text);-webkit-box-decoration-break:clone;box-decoration-break:clone;border-radius:.22em;padding:.02em .18em;font-weight:750}.context-question{margin-top:var(--space-5);color:var(--color-text-muted);letter-spacing:-.015em;font-family:inherit;font-size:clamp(1.02rem,3.2vw,1.15rem);font-weight:600;line-height:1.35}.context-answer{gap:var(--space-4);margin-top:var(--space-4);padding-top:var(--space-4);border-top:1px solid var(--color-border);display:grid}.context-card[data-revealed=true] 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solid;border-radius:.3rem;padding:.12em .42em;font-size:.75em;font-weight:600}.rating-controls{border:0;min-width:0;margin:0;padding:0}.rating-controls legend{width:100%;margin-bottom:var(--space-3);color:var(--color-text-muted);text-align:center;font-size:.8125rem;font-weight:600}.rating-grid{gap:var(--space-2);grid-template-columns:repeat(2,minmax(0,1fr));display:grid}.rating-button{justify-content:space-between;align-items:center;gap:var(--space-2);border:1px solid var(--color-border);border-radius:var(--radius-small);background:var(--color-surface);min-width:0;min-height:3rem;color:var(--color-text);cursor:pointer;padding:.65rem .85rem;font-weight:650;display:inline-flex}.rating-button:hover:not(:disabled){border-color:var(--color-text-muted);background:var(--color-surface-muted)}.rating-button--good:hover:not(:disabled),.rating-button--easy:hover:not(:disabled){border-color:var(--color-accent)}.rating-button:disabled{cursor:wait;opacity:.6}.route-notice{margin-block:var(--space-7)}.login-page,.settings-page{gap:var(--space-6);display:grid}.auth-layout{width:min(100%,32rem);margin-inline:auto}.auth-heading{gap:var(--space-3);display:grid}.auth-form,.settings-form{gap:var(--space-4);display:grid}.field{gap:var(--space-2);min-width:0;font-weight:650;display:grid}.field input{border:1px solid var(--color-border);border-radius:var(--radius-small);background:var(--color-surface);width:100%;min-width:0;min-height:3rem;color:var(--color-text);padding:.7rem .85rem;font-size:1rem;font-weight:500}.field input:hover{border-color:var(--color-text-muted)}.field 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var(--color-border);border-radius:var(--radius-medium);background:var(--color-surface);display:grid}.settings-section>div:first-child{gap:var(--space-2);display:grid}.choice-fieldset{border-radius:var(--radius-small);background:var(--color-surface-muted);border:0;grid-template-columns:repeat(3,minmax(0,1fr));gap:.2rem;min-width:0;margin:0;padding:.2rem;display:grid}.choice-option{justify-content:center;align-items:center;gap:var(--space-2);min-width:0;min-height:2.75rem;padding:var(--space-2);border-radius:calc(var(--radius-small) - .1rem);cursor:pointer;border:0;font-weight:550;display:flex;position:relative}.choice-option:has(input:checked){background:var(--color-surface);color:var(--color-text);box-shadow:var(--shadow-soft);font-weight:650}.choice-option:has(input:focus-visible){outline:2px solid var(--color-focus);outline-offset:2px}.choice-option input{opacity:0;cursor:pointer;width:100%;height:100%;margin:0;position:absolute;inset:0}.choice-option input:focus,.choice-option input:focus-visible{outline:none}@media (max-width:41.99rem){.study-page{padding-bottom:calc(10rem + env(safe-area-inset-bottom))}.study-actions{width:100%;padding-right:max(var(--space-4), env(safe-area-inset-right));padding-left:max(var(--space-4), env(safe-area-inset-left));box-shadow:var(--shadow-sticky);margin-inline:0;position:fixed;left:0;right:0}.study-actions>*{width:min(100%, var(--content-width));margin-inline:auto}}@media (min-width:42rem){.module-grid,.queue-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.rating-grid{grid-template-columns:repeat(4,minmax(0,1fr))}.study-actions{margin-inline:0;padding-inline:0}}@media (max-width:31rem){.home-heading,.today-heading,.study-heading{flex-direction:column;align-items:flex-start}.progress-grid{grid-template-columns:1fr}.progress-item+.progress-item{border-top:1px solid var(--color-border);border-left:0}.sync-status{white-space:normal}.choice-fieldset{grid-template-columns:1fr}.choice-option{padding-inline:var(--space-4);justify-content:flex-start}}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.01ms!important;animation-duration:.01ms!important;animation-iteration-count:1!important}}