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12px;font-size:13px;line-height:1.6}.card-video-link{color:var(--accent-dark);margin-top:2px;font-size:12px;font-weight:600;text-decoration:none;display:inline-block}.flashcard-thumb-bar{z-index:990;padding:10px 16px max(14px, env(safe-area-inset-bottom,14px));-webkit-backdrop-filter:blur(16px);border-top:1px solid var(--line);background:#f8f7f2f0;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;max-width:720px;margin:0 auto;animation:.18s ease-out updateToastSlideUp;display:grid;position:fixed;bottom:0;left:0;right:0}.thumb-action-btn{border-radius:var(--radius-md);border:1px solid var(--line);-webkit-user-select:none;user-select:none;flex-direction:column;justify-content:center;align-items:center;gap:2px;min-height:54px;padding:6px 4px;transition:all .12s;display:flex}.thumb-action-btn:active{transform:scale(.96)}.btn-title{font-size:13.5px;font-weight:750;line-height:1.2}.btn-subtitle{opacity:.8;font-size:9.5px;line-height:1}.thumb-action-btn:disabled{opacity:.5;cursor:default}.tone-again{background:var(--rose-light);color:var(--rose-dark);border-color:var(--rose)}.tone-hard{background:var(--paper-subtle);color:var(--ink)}.tone-good{background:var(--accent-light);color:var(--accent-dark);border-color:var(--accent)}.tone-easy{background:var(--green-light);color:var(--green-dark);border-color:var(--green)}.review-error{color:var(--rose-dark)}.daily-new-limit{align-items:center;gap:10px;margin-top:12px;font-size:13px;display:flex}.daily-new-limit input{border:1px solid var(--line);border-radius:var(--radius-md);background:var(--paper-raised);width:70px;color:var(--ink);padding:6px}.session-daily-stats{color:var(--muted);text-align:center;margin:0;font-size:12px;line-height:1.6}.review-history{color:var(--muted);overflow-wrap:anywhere;font-size:12px;line-height:1.6}@media (width<=480px){.flashcard-thumb-bar{grid-template-columns:repeat(2,minmax(0,1fr))}}.completion-card{border-radius:var(--radius-xl);background:var(--paper-raised);border:1px solid var(--line);box-shadow:var(--shadow-md);text-align:center;flex-direction:column;align-items:center;gap:16px;padding:36px 20px;display:flex}.completion-badge{background:var(--green-light);width:52px;height:52px;color:var(--green);border:1.5px solid 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.15s;display:flex}.primary-cta{background:var(--accent);color:#261d05;box-shadow:0 4px 12px #d89f1840}.secondary-cta{background:var(--paper-raised);border:1px solid var(--line);color:var(--ink)}@media (width>=641px){.study-shell{padding:24px 24px 60px}.flashcard-thumb-bar{-webkit-backdrop-filter:none;background:0 0;border:none;padding:0;position:static}.session-shell{padding-bottom:40px}.thumb-action-btn{min-height:60px}.btn-title{font-size:14.5px}.completion-btn-group{flex-direction:row;max-width:380px}}