* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #0a0a0a;
    color: #e0e0e0;
    min-height: 100vh;
}

/* ─── Landing ──────────────────────────────────────────────────── */
.landing {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    text-align: center;
    padding: 2rem;
}

.landing h1 {
    font-size: 3.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, #fff 0%, #888 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.landing .subtitle {
    font-size: 1.2rem;
    color: #888;
    margin-bottom: 2.5rem;
    max-width: 500px;
}

.landing .how-it-works {
    display: flex;
    gap: 2rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
    justify-content: center;
}

.landing .step {
    background: #1a1a1a;
    border: 1px solid #2a2a2a;
    border-radius: 12px;
    padding: 1.5rem;
    width: 180px;
    text-align: center;
}

.landing .step .num {
    font-size: 2rem;
    font-weight: 700;
    color: #4a9eff;
    margin-bottom: 0.5rem;
}

.landing .step p { font-size: 0.9rem; color: #aaa; }

.btn {
    background: #fff;
    color: #000;
    border: none;
    padding: 1rem 3rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.2s;
}

.btn:hover { transform: scale(1.05); box-shadow: 0 0 30px rgba(255,255,255,0.15); }
.btn:disabled { opacity: 0.4; cursor: not-allowed; transform: none; }

.btn-small {
    padding: 0.6rem 1.5rem;
    font-size: 0.9rem;
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 1px solid #444;
}

.btn-outline:hover { border-color: #888; background: #1a1a1a; }

/* ─── Quiz ─────────────────────────────────────────────────────── */
.quiz { display: none; padding: 1rem; max-width: 1400px; margin: 0 auto; }

.progress-bar {
    display: flex;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: 1.5rem;
    padding-top: 1rem;
}

.progress-dot {
    width: 12px; height: 12px;
    border-radius: 50%;
    background: #2a2a2a;
    border: 2px solid #333;
    transition: all 0.3s;
}

.progress-dot.active { border-color: #4a9eff; background: #4a9eff; }
.progress-dot.correct { border-color: #4ade80; background: #4ade80; }
.progress-dot.incorrect { border-color: #f87171; background: #f87171; }
.progress-dot.cant-tell { border-color: #fbbf24; background: #fbbf24; }

.round-label {
    text-align: center;
    font-size: 0.9rem;
    color: #666;
    margin-bottom: 0.5rem;
}

.question {
    text-align: center;
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
}

.image-pair {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.image-option {
    position: relative;
    border-radius: 12px;
    overflow: hidden;
    cursor: pointer;
    border: 3px solid transparent;
    transition: all 0.3s;
    background: #111;
}

.image-option:hover { border-color: #4a9eff; transform: scale(1.01); }
.image-option.selected { border-color: #4a9eff; }
.image-option.correct-reveal { border-color: #4ade80; }
.image-option.incorrect-reveal { border-color: #f87171; }
.image-option.disabled { cursor: default; pointer-events: none; }

.image-option img {
    width: 100%;
    height: 450px;
    display: block;
    object-fit: cover;
    background: #1a1a1a;
}

@media (max-width: 768px) {
    .image-option img { height: 250px; }
}

.image-label {
    position: absolute;
    top: 12px;
    left: 12px;
    background: rgba(0,0,0,0.7);
    backdrop-filter: blur(10px);
    padding: 0.4rem 1rem;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.9rem;
}

.image-badge {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 0.4rem 1rem;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.8rem;
    display: none;
}

.image-badge.ai { background: #f87171; color: #fff; }
.image-badge.real { background: #4ade80; color: #000; }
.image-badge.show { display: block; }

/* ─── Can't Tell Button ────────────────────────────────────────── */
.cant-tell-section {
    text-align: center;
    margin-bottom: 1.5rem;
}

.btn-cant-tell {
    background: transparent;
    color: #fbbf24;
    border: 1px solid #fbbf24;
    padding: 0.7rem 2rem;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-cant-tell:hover {
    background: rgba(251, 191, 36, 0.1);
    transform: scale(1.05);
    box-shadow: 0 0 20px rgba(251, 191, 36, 0.15);
}

.btn-cant-tell:disabled {
    opacity: 0.3;
    cursor: not-allowed;
    transform: none;
}

.reason-section {
    max-width: 600px;
    margin: 0 auto 1.5rem;
    text-align: center;
}

.reason-section label {
    display: block;
    font-size: 0.9rem;
    color: #888;
    margin-bottom: 0.5rem;
}

.reason-input {
    width: 100%;
    padding: 0.8rem 1rem;
    background: #1a1a1a;
    border: 1px solid #333;
    border-radius: 8px;
    color: #e0e0e0;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

.reason-input:focus { border-color: #4a9eff; }

.actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

/* ─── Feedback ─────────────────────────────────────────────────── */
.feedback {
    text-align: center;
    padding: 1rem;
    margin-bottom: 1rem;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    display: none;
}

.feedback.correct { background: rgba(74,222,128,0.15); color: #4ade80; display: block; }
.feedback.incorrect { background: rgba(248,113,113,0.15); color: #f87171; display: block; }
.feedback.cant-tell { background: rgba(251,191,36,0.15); color: #fbbf24; display: block; }

/* ─── Results ──────────────────────────────────────────────────── */
.results { display: none; padding: 2rem; max-width: 800px; margin: 0 auto; text-align: center; }

.results h2 { font-size: 2rem; margin-bottom: 0.5rem; }

.score-display {
    font-size: 5rem;
    font-weight: 700;
    margin: 1rem 0;
}

.score-display .correct-count { color: #4ade80; }
.score-display .total { color: #666; }

.score-message {
    font-size: 1.1rem;
    color: #888;
    margin-bottom: 2rem;
}

.result-list { text-align: left; margin-bottom: 2rem; }

.result-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: #1a1a1a;
    border-radius: 8px;
    margin-bottom: 0.5rem;
}

.result-icon { font-size: 1.5rem; flex-shrink: 0; }
.result-title { flex: 1; }
.result-title .collection { font-size: 0.8rem; color: #666; }

/* ─── Footer ──────────────────────────────────────────────────── */
.site-footer {
    text-align: center;
    padding: 1.5rem;
    color: #444;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
}

/* ─── Responsive ───────────────────────────────────────────────── */
@media (max-width: 768px) {
    .landing h1 { font-size: 2.2rem; }
    .image-pair { grid-template-columns: 1fr; }
    .question { font-size: 1.1rem; }
    .landing .how-it-works { flex-direction: column; align-items: center; }
}