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rgba(83, 155, 245, .15);--backdrop: rgba(0, 0, 0, .7);--streak-fg: #ff8c00;--streak-bg: rgba(255, 140, 0, .2);--success-bg-subtle: rgba(87, 171, 90, .15);--shadow-small: 0 1px 2px rgba(0, 0, 0, .2);--shadow-medium: 0 3px 6px rgba(0, 0, 0, .3), 0 2px 4px rgba(0, 0, 0, .2);--shadow-hover: 0 4px 12px rgba(0, 0, 0, .3);--shadow-card: 0 4px 16px rgba(0, 0, 0, .35), 0 2px 6px rgba(0, 0, 0, .2);--answer-glow: 0 0 12px rgba(87, 171, 90, .4)}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Noto Sans,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";background:var(--canvas-default);min-height:100vh;display:flex;align-items:center;justify-content:center;color:var(--text-primary);transition:background-color .15s ease}.container{display:flex;flex-direction:column;align-items:center;justify-content:center;width:100%;max-width:544px;padding:96px 24px 48px;min-height:100vh}#question-area{display:flex;flex-direction:column;width:100%;max-width:544px}h1{font-size:24px;color:var(--text-primary);margin-bottom:8px;text-align:center;font-weight:600}.app-header{text-align:center;margin-bottom:24px}.logo{display:flex;align-items:center;justify-content:center;gap:12px}.logo h1{margin-bottom:0;font-size:24px}.logo-icon{font-family:ui-monospace,SFMono-Regular,SF Mono,Menlo,Consolas,Liberation Mono,monospace;font-size:16px;font-weight:600;color:var(--accent-fg);background:var(--canvas-subtle);padding:8px 10px;border-radius:8px;border:1px solid var(--border-default);letter-spacing:1px}.tagline{font-size:14px;color:var(--text-secondary);margin-top:8px}.stats-bar{display:flex;align-items:center;justify-content:space-between;padding:12px 16px;background:var(--canvas-subtle);border:1px solid var(--border-muted);border-radius:8px;margin-bottom:24px}.total-cards{font-size:13px;color:var(--text-secondary)}.main-stats{display:flex;align-items:center;gap:12px}.streak-badge{font-size:13px;font-weight:600;color:var(--streak-fg);background:var(--streak-bg);padding:2px 8px;border-radius:12px;display:flex;align-items:center;gap:4px}.header{width:100%;margin-bottom:32px}.header h1{margin-bottom:0;font-size:20px;text-align:center}.reset-history-btn{padding:6px 12px;font-size:12px;font-weight:500;color:var(--text-secondary);background:transparent;border:1px solid var(--border-muted);border-radius:6px;cursor:pointer;transition:background .15s ease,border-color .15s ease,transform .1s ease}.back-button{align-self:flex-start;margin-bottom:24px;padding:8px 16px;border-radius:6px;border:1px solid var(--button-border);background:var(--button-bg);color:var(--text-primary);font-size:14px;font-weight:500;cursor:pointer;transition:background .15s ease,border-color .15s ease}.back-button:hover{background:var(--button-bg-hover);border-color:var(--button-border-hover)}.back-button:active{transform:scale(.98)}.back-button:focus-visible{outline:none;box-shadow:0 0 0 3px var(--keyboard-hint-bg)}.reset-history-btn:hover:not(:disabled){background:var(--button-bg);border-color:var(--button-border);color:var(--text-primary)}.reset-history-btn:active:not(:disabled){transform:scale(.98)}.reset-history-btn:disabled{opacity:.5;cursor:not-allowed}.reset-history-btn:focus-visible{outline:none;box-shadow:0 0 0 3px var(--keyboard-hint-bg)}.back-button-fixed{position:fixed;top:16px;left:16px;z-index:900}@media(max-width:600px){.container{height:100dvh;min-height:0;padding:56px 8px 8px;justify-content:flex-start;overflow-y:auto}#question-area{flex:1;min-height:0}.header{margin-bottom:12px}h1{font-size:20px}.header h1{font-size:18px}.subtitle{font-size:13px;margin-bottom:24px}}@media(min-width:769px){.container{padding-top:120px;max-width:900px}.back-button-fixed{top:24px;left:24px}}