@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&display=swap');

:root {
    --primary: #6366f1;
    --primary-light: #818cf8;
    --secondary: #a855f7;
    --bg-dark: #0f172a;
    --card-bg: #1e293b;
    --text-light: #f8fafc;
    --text-muted: #94a3b8;
    --glass: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --success: #00e676;
    --error: #ef5350;
    --info: #7bdff2;
    --accent: #ffd166;
    --shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    --grad-primary: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);

    /* keep legacy names used by canvas overlay colors */
    --spot-diff-success: #00e676;
    --spot-diff-error: #ef5350;
    --spot-diff-muted: #94a3b8;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: 'Outfit', sans-serif;
    color: var(--text-light);
    background-color: var(--bg-dark);
    background-image:
        radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.15) 0px, transparent 50%),
        radial-gradient(at 100% 0%, rgba(168, 85, 247, 0.15) 0px, transparent 50%);
    min-height: 100vh;
    padding-top: 100px;
    overflow-x: hidden;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to   { opacity: 1; transform: translateY(0); }
}

.hidden { display: none !important; }

.spot-diff-top-ad { margin: 0 auto 20px; max-width: 1100px; }

.spot-diff-page {
    max-width: 1100px;
    margin: 0 auto 48px;
    padding: 0 16px 32px;
    animation: slideUp 0.6s cubic-bezier(0.23, 1, 0.32, 1);
}

/* Shared glass surface */
.spot-diff-header-card,
.spot-diff-hud-card,
.spot-diff-feedback-card,
.spot-diff-records-card,
.spot-diff-start-card,
.spot-diff-complete-card,
.spot-diff-scene-frame {
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    box-shadow: var(--shadow);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
}

/* Header */
.spot-diff-header-card {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    align-items: center;
    padding: 20px 24px;
    margin-bottom: 20px;
}

.spot-diff-header-card h1 {
    margin: 0;
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: clamp(1.4rem, 3vw, 2rem);
    font-weight: 800;
    background: var(--grad-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.spot-diff-header-card h1 .header-game-icon {
    -webkit-text-fill-color: initial;
    filter: drop-shadow(0 0 8px rgba(99, 102, 241, 0.5));
}

.spot-diff-header-card p {
    margin: 6px 0 0;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Back button */
.back-btn {
    padding: 10px 20px;
    background: var(--glass);
    border: 1px solid var(--glass-border);
    border-radius: 14px;
    color: var(--text-light);
    cursor: pointer;
    font-family: 'Outfit', sans-serif;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all 0.3s;
    white-space: nowrap;
    flex-shrink: 0;
}
.back-btn:hover { background: rgba(255, 255, 255, 0.1); transform: translateX(-4px); }

/* Desktop two-column layout */
.spot-diff-layout {
    display: grid;
    grid-template-columns: 1fr 280px;
    gap: 20px;
    align-items: start;
}

.spot-diff-main { min-width: 0; }

.spot-diff-sidebar {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* Shell */
.spot-diff-shell { position: relative; }

/* HUD */
.spot-diff-hud {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
    margin-bottom: 14px;
}

.spot-diff-hud-card { padding: 14px 16px; }

.spot-diff-label {
    display: block;
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.spot-diff-hud-card strong {
    font-size: clamp(1rem, 2vw, 1.25rem);
    font-weight: 800;
}

/* Stage — two canvas frames side by side */
.spot-diff-stage {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
}

.spot-diff-scene-frame {
    padding: 8px;
    position: relative;
    overflow: hidden;
}

.spot-diff-canvas {
    display: block;
    width: 100%;
    aspect-ratio: 4 / 3;
    border-radius: 12px;
    cursor: crosshair;
    touch-action: none;
}

.spot-diff-scene-caption {
    margin: 8px 4px 2px;
    color: var(--text-muted);
    font-size: 0.82rem;
    text-align: center;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

/* Miss animation */
.spot-miss {
    position: absolute;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: 3px solid var(--error);
    transform: translate(-50%, -50%);
    pointer-events: none;
    animation: spot-miss-anim 0.6s ease-out forwards;
    z-index: 10;
}

@keyframes spot-miss-anim {
    0%   { opacity: 1; transform: translate(-50%, -50%) scale(0.5); }
    50%  { opacity: 0.9; transform: translate(-50%, -50%) scale(1.3); }
    100% { opacity: 0; transform: translate(-50%, -50%) scale(1.8); }
}

/* Sidebar cards */
.spot-diff-feedback-card,
.spot-diff-records-card { padding: 20px; }

.spot-diff-feedback-card h2,
.spot-diff-records-card h2 {
    margin: 0 0 12px;
    font-size: 1rem;
    font-weight: 700;
}

/* Feedback text states */
.spot-diff-feedback-text {
    min-height: 1.4em;
    font-size: 0.9rem;
    color: var(--text-muted);
    margin: 0 0 14px;
    transition: color 0.25s;
    font-weight: 500;
}
.spot-diff-feedback-success { color: var(--success) !important; }
.spot-diff-feedback-error   { color: var(--error) !important; }
.spot-diff-feedback-info    { color: var(--info) !important; }

/* Buttons */
.spot-diff-primary-btn,
.spot-diff-secondary-btn {
    border: 0;
    border-radius: 14px;
    padding: 11px 20px;
    font-family: 'Outfit', sans-serif;
    font-size: 0.9rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.25s ease;
    width: 100%;
}

.spot-diff-primary-btn {
    background: var(--grad-primary);
    color: #fff;
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.35);
}

.spot-diff-secondary-btn {
    background: var(--glass);
    color: var(--text-light);
    border: 1px solid var(--glass-border);
}

.spot-diff-primary-btn:hover { transform: translateY(-2px); box-shadow: 0 12px 28px rgba(99, 102, 241, 0.45); }
.spot-diff-secondary-btn:hover { background: rgba(255, 255, 255, 0.1); transform: translateY(-2px); }
.spot-diff-primary-btn:disabled,
.spot-diff-secondary-btn:disabled { opacity: 0.45; cursor: not-allowed; transform: none; }

/* Start screen overlay */
.spot-diff-start-screen {
    position: absolute;
    inset: 0;
    z-index: 4;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(8, 15, 30, 0.78);
    border-radius: 20px;
    backdrop-filter: blur(4px);
}

.spot-diff-start-card {
    width: min(100%, 400px);
    text-align: center;
    padding: 30px 26px;
}

.spot-diff-kicker {
    margin: 0 0 8px;
    font-size: 2.4rem;
    letter-spacing: 0;
}

.spot-diff-start-card h2 {
    margin: 0 0 6px;
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--grad-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.spot-diff-start-card > p {
    margin: 0 0 20px;
    color: var(--text-muted);
    font-size: 0.88rem;
}

/* Name input group in start card */
.spot-diff-name-group {
    margin-bottom: 16px;
    text-align: left;
}

.spot-diff-name-group label {
    display: block;
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.07em;
    margin-bottom: 6px;
}

.spot-diff-name-input {
    width: 100%;
    background: rgba(15, 23, 42, 0.7);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 11px 16px;
    color: var(--text-light);
    font-family: 'Outfit', sans-serif;
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s;
}
.spot-diff-name-input:focus { border-color: var(--primary); }
.spot-diff-name-input::placeholder { color: var(--text-muted); }

/* Complete card */
.spot-diff-complete-card {
    margin-top: 20px;
    padding: 36px 28px;
    text-align: center;
}

.spot-diff-complete-card .spot-diff-kicker { font-size: 2.8rem; }

.spot-diff-complete-card h2 {
    margin: 0 0 8px;
    font-size: 2rem;
    font-weight: 800;
    background: var(--grad-primary);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.spot-diff-complete-card > p {
    margin: 0 0 16px;
    color: var(--text-muted);
    font-size: 1rem;
}

.spot-diff-complete-time {
    margin: 0 0 28px;
    font-size: 1rem;
    color: var(--text-muted);
}

.spot-diff-complete-time strong {
    color: var(--accent);
    font-size: 2.2rem;
    font-weight: 800;
    margin-left: 8px;
}

.spot-diff-complete-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    flex-wrap: wrap;
    max-width: 380px;
    margin: 0 auto;
}

.spot-diff-complete-actions .spot-diff-primary-btn,
.spot-diff-complete-actions .spot-diff-secondary-btn {
    width: auto;
    min-width: 140px;
}

/* Records widget override */
.records-widget {
    margin: 0 !important;
    background: transparent !important;
    border: 0 !important;
    box-shadow: none !important;
    padding: 0 !important;
}

/* Responsive */
@media (max-width: 860px) {
    .spot-diff-layout { grid-template-columns: 1fr; }
    body { padding-top: 80px; }
}

@media (max-width: 640px) {
    .spot-diff-hud { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .spot-diff-header-card { flex-wrap: wrap; }
    .spot-diff-stage { gap: 8px; }
}