/* ================================================================
   隔熱紙透光度反應力測驗 — Dark Mode Style
   Imports shared design system variables via body parent
================================================================ */
@import url('https://fonts.googleapis.com/css2?family=Figtree:wght@400;500;600;700;800&family=Noto+Sans+TC:wght@400;500;700&display=swap');

/* ── Design Tokens (local copy for standalone page) ── */
:root {
    --bg-base:      #070B14;
    --bg-surface:   #0D1525;
    --bg-elevated:  #152035;
    --bg-hover:     #1A2B44;
    --border:       rgba(255,255,255,0.07);
    --border-md:    rgba(255,255,255,0.12);
    --border-active:rgba(6,182,212,0.45);
    --text-primary:   #F0F4FF;
    --text-secondary: #8899B4;
    --text-muted:     #4E6080;
    --cyan:       #06B6D4;
    --cyan-light: #22D3EE;
    --cyan-dim:   rgba(6,182,212,0.15);
    --cyan-glow:  rgba(6,182,212,0.25);
    --green:      #10B981;
    --green-dim:  rgba(16,185,129,0.15);
    --red:        #EF4444;
    --red-dim:    rgba(239,68,68,0.15);
    --amber:      #F59E0B;
    --amber-dim:  rgba(245,158,11,0.15);
    --r-sm: 8px; --r-md: 12px; --r-lg: 16px; --r-xl: 20px;
    --shadow-md: 0 4px 16px rgba(0,0,0,.5);
    --t-fast: 150ms ease; --t-base: 200ms ease;
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { min-height: 100vh; width: 100%; overscroll-behavior: none; -webkit-overflow-scrolling: touch; }

body {
    font-family: 'Figtree', 'Noto Sans TC', -apple-system, BlinkMacSystemFont, sans-serif;
    background-color: var(--bg-base);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    display: flex;
    flex-direction: column;
}

/* ── Header ── */
.site-header {
    background: var(--bg-surface);
    border-bottom: 1px solid var(--border);
    padding: 14px 16px;
    display: flex;
    align-items: center;
    gap: 10px;
    position: sticky;
    top: 0;
    z-index: 100;
}
.site-header h1 { font-size: .95rem; font-weight: 700; color: var(--text-primary); }
.header-icon {
    width: 34px; height: 34px;
    background: var(--amber-dim);
    border: 1px solid rgba(245,158,11,.3);
    border-radius: var(--r-sm);
    display: flex; align-items: center; justify-content: center;
    color: var(--amber); flex-shrink: 0;
}
.header-icon svg { width: 16px; height: 16px; }
.back-link {
    margin-left: auto;
    display: inline-flex; align-items: center; gap: 5px;
    font-size: .78rem; font-weight: 600; color: var(--text-secondary);
    text-decoration: none; padding: 5px 10px;
    border-radius: var(--r-sm); border: 1px solid var(--border-md);
    transition: color var(--t-fast), border-color var(--t-fast), background var(--t-fast);
}
.back-link:hover { color: var(--cyan); border-color: var(--border-active); background: var(--cyan-dim); }
.back-link svg { width: 13px; height: 13px; }

/* ── Container ── */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px 16px 40px;
    width: 100%;
}

/* ── Info Panel ── */
.info-panel {
    display: flex;
    justify-content: space-around;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 12px;
    margin-bottom: 16px;
    padding: 16px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--r-xl);
}

.transparency-control,
.target-mode-control {
    display: flex; flex-direction: column; gap: 6px; align-items: center;
}
.transparency-control label,
.target-mode-control label {
    font-size: .72rem; font-weight: 700;
    color: var(--text-muted); text-transform: uppercase;
    letter-spacing: .06em; text-align: center;
}

/* ── Select ── */
.transparency-select,
.target-mode-select {
    padding: 9px 32px 9px 12px;
    font-size: .88rem; font-family: inherit;
    border: 1px solid var(--border-md);
    border-radius: var(--r-md);
    background: var(--bg-elevated);
    color: var(--text-primary);
    cursor: pointer;
    transition: border-color var(--t-fast), box-shadow var(--t-fast);
    min-width: 130px;
    appearance: none; -webkit-appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='none' stroke='%238899B4' stroke-width='2' viewBox='0 0 24 24'%3E%3Cpolyline points='6 9 12 15 18 9'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 10px center;
}
.transparency-select:focus,
.target-mode-select:focus {
    outline: none;
    border-color: var(--border-active);
    box-shadow: 0 0 0 3px var(--cyan-dim);
}

/* ── Reaction Stats ── */
.reaction-time, .best-time {
    text-align: center;
    font-size: .82rem; color: var(--text-secondary);
}
.reaction-time span, .best-time span {
    color: var(--cyan-light);
    font-weight: 700; font-variant-numeric: tabular-nums;
}

/* ── Game Notice ── */
.game-notice {
    text-align: center;
    color: #FDE68A;
    font-size: .85rem;
    font-weight: 600;
    margin-bottom: 12px;
    padding: 10px 14px;
    background: var(--amber-dim);
    border: 1px solid rgba(245,158,11,.2);
    border-radius: var(--r-md);
}

/* ── Target Area ── */
.target-area {
    width: 100%; height: 400px;
    border-radius: var(--r-xl);
    position: relative; overflow: hidden;
    background: url('IMG_20230405_183646.jpg') no-repeat center center;
    background-size: cover;
    border: 1px solid var(--border-md);
    box-shadow: var(--shadow-md);
}

.target {
    position: absolute;
    width: 90px; height: 90px;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 0 20px rgba(6,182,212,.5), 0 4px 12px rgba(0,0,0,.4);
    transition: transform .15s ease, box-shadow .15s ease;
    opacity: 0;
    z-index: 1;
}
.target:hover {
    transform: scale(1.08);
    box-shadow: 0 0 32px rgba(6,182,212,.7), 0 6px 16px rgba(0,0,0,.5);
}

/* ── Controls ── */
.controls {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin: 16px 0;
    flex-wrap: wrap;
}

button {
    padding: 11px 22px;
    font-size: .9rem; font-weight: 700; font-family: inherit;
    border: none; border-radius: var(--r-md);
    cursor: pointer;
    transition: background var(--t-fast), box-shadow var(--t-fast), transform var(--t-fast);
    -webkit-tap-highlight-color: transparent;
    display: inline-flex; align-items: center; gap: 6px;
}
button:active { transform: scale(.97); }

#startBtn { background: var(--green); color: #030712; }
#startBtn:hover { box-shadow: 0 0 16px rgba(16,185,129,.4); }

#shareBtn { background: var(--cyan); color: #030712; }
#shareBtn:hover { box-shadow: 0 0 16px var(--cyan-glow); }

button:disabled {
    background: var(--bg-elevated) !important;
    color: var(--text-muted) !important;
    cursor: not-allowed; box-shadow: none !important;
    border: 1px solid var(--border-md);
}

.stats-btn {
    padding: 11px 22px;
    font-size: .9rem; font-weight: 700; font-family: inherit;
    border: 1px solid var(--border-md); border-radius: var(--r-md);
    cursor: pointer; text-decoration: none;
    background: transparent; color: var(--text-secondary);
    display: inline-flex; align-items: center; gap: 6px;
    transition: color var(--t-fast), border-color var(--t-fast), background var(--t-fast);
}
.stats-btn:hover { color: var(--text-primary); border-color: var(--border-active); background: var(--bg-elevated); }

/* ── Results ── */
.results {
    margin-top: 16px;
    padding: 20px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--r-xl);
    max-height: 60vh;
    overflow-y: auto;
}
.results h2 { font-size: 1.1rem; font-weight: 700; color: var(--text-primary); margin-bottom: 16px; }

.stats-summary, .attempts-list {
    background: var(--bg-elevated);
    padding: 16px;
    border-radius: var(--r-lg);
    margin-bottom: 12px;
}
.stats-summary p {
    font-size: .9rem; color: var(--text-secondary);
    margin: 8px 0; font-weight: 500;
}
.stats-summary p strong { color: var(--cyan-light); }

.attempts-list h3 { font-size: .9rem; font-weight: 700; color: var(--text-primary); margin-bottom: 12px; }
.attempts-list ul { list-style: none; padding: 0; }
.attempts-list li {
    padding: 8px 0; border-bottom: 1px solid var(--border);
    font-size: .86rem; color: var(--text-secondary);
}
.attempts-list li:last-child { border-bottom: none; }

/* ── Countdown ── */
.countdown {
    position: absolute; top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    font-size: 80px; font-weight: 800;
    color: #fff;
    text-shadow: 0 0 30px var(--cyan-glow), 0 4px 12px rgba(0,0,0,.6);
    z-index: 1000;
    font-variant-numeric: tabular-nums;
}

/* ── Overlay layers (game mechanics — preserved) ── */
.target-area::before {
    content: '';
    position: absolute; top: 0; left: 0; width: 100%; height: 100%;
    pointer-events: none; z-index: 2;
}
.target { z-index: 1; }
.countdown { z-index: 3; }

.target-area.dark::before      { background-color: rgba(0,0,0,0.3); }
.target-area.darker::before    { background-color: rgba(0,0,0,0.5); }
.target-area.darkest::before   { background-color: rgba(0,0,0,0.7); }
.target-area.darkest[data-transparency="20"]::before { background-color: rgba(0,0,0,0.8); }
.target-area.darkest[data-transparency="10"]::before { background-color: rgba(0,0,0,0.9); }

/* ── Mobile ── */
@media (max-width: 768px) {
    .container { padding: 12px 12px 32px; }
    .info-panel { flex-direction: column; gap: 10px; padding: 12px; }
    .transparency-select, .target-mode-select { width: 100%; max-width: none; font-size: 16px; height: 44px; }
    .info-panel > div { width: 100%; text-align: center; }
    .target-area { height: auto; min-height: 280px; border-radius: var(--r-lg); }
    .target { width: 64px; height: 64px; }
    button { min-height: 44px; font-size: 15px; padding: 10px 18px; touch-action: manipulation; }
    .stats-btn { min-height: 44px; font-size: 15px; }
    .results { max-height: 50vh; }
}

@media (hover: none) {
    .target:hover { transform: none; }
    button:hover:not(:disabled) { transform: none; box-shadow: none !important; }
}

/* ── Animations ── */
@keyframes fadeUp { from{opacity:0;transform:translateY(8px)} to{opacity:1;transform:translateY(0)} }

/* ── Prefers reduced motion ── */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}