/* Sokoban — Indigo */
:root {
    --sk-accent: #6366F1;
    --sk-accent-light: #C7D2FE;
    --sk-accent-dark: #312E81;
    --sk-bg: #0A0820;
    --sk-surface: #14112E;
    --sk-surface-light: #1F1A40;
    --sk-text: #E8E6FA;
    --sk-text-dim: #9C97CC;
    --sk-floor: #16133A;
    --sk-floor-target: #2A1640;
    --sk-wall: #4F4990;
    --sk-box: #F59E0B;
    --sk-box-done: #34D399;
    --sk-player: #F9A8D4;
    --sk-gold: #FACC15;
}
.sk-layout { display: flex; justify-content: center; gap: 20px; max-width: 1200px; margin: 0 auto; padding: 20px; min-height: calc(100vh - 80px); }
.ad-slot { width: 160px; flex-shrink: 0; }
.ad-slot--left, .ad-slot--right { display: flex; align-items: flex-start; }
.ad-placeholder--vertical { width: 160px; height: 600px; background: var(--sk-surface); border: 1px dashed var(--sk-text-dim); display: flex; align-items: center; justify-content: center; color: var(--sk-text-dim); font-size: 12px; border-radius: 8px; }
#sokoban-app { flex: 1; max-width: 720px; min-width: 320px; color: var(--sk-text); }
.screen { display: none; }
.screen.active { display: block; animation: skFade .3s ease; }
@keyframes skFade { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }
.sk-header { text-align: center; padding: 36px 0 24px; }
.sk-logo { display: inline-flex; gap: 10px; padding: 12px 18px; background: var(--sk-surface); border: 1px solid var(--sk-surface-light); border-radius: 12px; margin-bottom: 14px; }
.sk-box { width: 28px; height: 28px; background: linear-gradient(135deg, var(--sk-box), #B45309); border-radius: 4px; box-shadow: inset 0 0 6px rgba(0,0,0,0.4); }
.sk-box--target { background: linear-gradient(135deg, var(--sk-box-done), #047857); }
.sk-header h1 { font-family: 'Syne', sans-serif; font-size: 2.2rem; font-weight: 800; color: var(--sk-accent-light); letter-spacing: 4px; margin: 0; text-shadow: 0 0 24px rgba(99,102,241,0.5); }
.subtitle { color: var(--sk-text-dim); font-size: 1rem; margin-top: 8px; }
.card { background: var(--sk-surface); border-radius: 14px; padding: 20px; margin-bottom: 16px; border: 1px solid var(--sk-surface-light); }
.card__title { font-family: 'Syne', sans-serif; font-size: 0.85rem; text-transform: uppercase; letter-spacing: 2px; color: var(--sk-accent-light); margin-bottom: 14px; }
.diff-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; }
.diff-btn { background: var(--sk-surface-light); border: 1.5px solid transparent; color: var(--sk-text); padding: 12px 6px; border-radius: 10px; cursor: pointer; display: flex; flex-direction: column; align-items: center; gap: 4px; font-family: 'JetBrains Mono', monospace; font-size: 0.85rem; transition: transform .12s, border-color .12s; }
.diff-btn:hover { transform: translateY(-2px); border-color: var(--sk-accent); }
.diff-btn.selected { background: linear-gradient(135deg, var(--sk-accent-dark), var(--sk-accent)); border-color: var(--sk-accent-light); }
.sk-rules { margin: 0; padding-left: 1.1rem; color: var(--sk-text-dim); line-height: 1.6; font-size: 0.92rem; }
.sk-rules li + li { margin-top: 6px; }
.btn { font-family: 'DM Sans', sans-serif; font-weight: 600; border-radius: 10px; border: none; cursor: pointer; padding: 12px 22px; transition: transform .12s, box-shadow .12s; font-size: 0.95rem; }
.btn:hover { transform: translateY(-1px); }
.btn--primary { background: linear-gradient(135deg, var(--sk-accent-dark), var(--sk-accent)); color: #fff; box-shadow: 0 6px 18px rgba(99,102,241,0.35); }
.btn--outline { background: transparent; border: 1.5px solid var(--sk-accent); color: var(--sk-accent-light); }
.btn--outline:hover { background: rgba(99,102,241,0.12); }
.btn--ghost { background: transparent; color: var(--sk-text-dim); }
.btn--lg { padding: 16px 36px; font-size: 1.05rem; }
.btn--sm { padding: 8px 14px; font-size: 0.85rem; }
.menu-actions { display: flex; flex-direction: column; align-items: center; gap: 8px; margin-top: 18px; }
#game-hud { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; background: var(--sk-surface); padding: 14px; border-radius: 12px; border: 1px solid var(--sk-surface-light); margin-bottom: 18px; }
.hud__cell { display: flex; flex-direction: column; align-items: center; gap: 2px; }
.hud__label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 1.5px; color: var(--sk-text-dim); }
.hud__value { font-family: 'JetBrains Mono', monospace; font-size: 1.2rem; font-weight: 700; color: var(--sk-accent-light); }
.sk-board-area { display: flex; justify-content: center; padding: 16px 0; }
.sk-board { display: grid; gap: 2px; padding: 14px; background: var(--sk-surface); border: 1px solid var(--sk-surface-light); border-radius: 14px; box-shadow: 0 18px 40px rgba(0,0,0,0.45); }
.sk-tile { width: 44px; height: 44px; border-radius: 4px; display: flex; align-items: center; justify-content: center; transition: transform 0.1s ease, background 0.15s ease; }
.sk-tile.empty { background: transparent; }
.sk-tile.floor { background: var(--sk-floor); }
.sk-tile.target { background: var(--sk-floor-target); box-shadow: inset 0 0 0 2px rgba(99,102,241,0.4); }
.sk-tile.wall {
    background: linear-gradient(135deg, var(--sk-wall), #312E81);
    box-shadow: inset 0 0 0 1px rgba(255,255,255,0.08);
}
.sk-tile.target::before { content: ""; width: 14px; height: 14px; border-radius: 50%; background: var(--sk-accent-light); box-shadow: 0 0 10px var(--sk-accent); }
.sk-tile .sk-piece {
    width: 36px; height: 36px;
    border-radius: 8px;
    display: flex; align-items: center; justify-content: center;
    font-family: 'JetBrains Mono', monospace;
    font-weight: 700;
    color: #1A140A;
    transition: transform 0.12s ease, background 0.2s ease;
}
.sk-piece.box { background: linear-gradient(135deg, var(--sk-box), #B45309); box-shadow: inset 0 0 6px rgba(0,0,0,0.4), 0 3px 10px rgba(0,0,0,0.45); }
.sk-piece.box.done { background: linear-gradient(135deg, var(--sk-box-done), #047857); color: #fff; }
.sk-piece.player {
    background: radial-gradient(circle, #FBCFE8 0%, var(--sk-player) 60%, #BE185D 100%);
    border-radius: 50%;
    box-shadow: 0 0 14px rgba(244,114,182,0.65);
}
.sk-pad { display: grid; grid-template-columns: repeat(3, 56px); gap: 8px; justify-content: center; margin-top: 8px; }
.sk-key { background: var(--sk-surface-light); border: 1.5px solid var(--sk-surface-light); color: var(--sk-accent-light); padding: 14px 0; border-radius: 10px; cursor: pointer; font-size: 1.2rem; transition: transform 0.08s ease, background 0.15s ease; }
.sk-key:hover { background: var(--sk-accent-dark); transform: translateY(-1px); }
.sk-actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 10px; margin-top: 14px; }
.result-card, .lb-card { background: var(--sk-surface); border-radius: 16px; padding: 36px 28px; border: 1px solid var(--sk-surface-light); text-align: center; max-width: 480px; margin: 40px auto; box-shadow: 0 18px 36px rgba(0,0,0,0.4); }
.result-card h2 { font-family: 'Syne', sans-serif; font-size: 2rem; color: var(--sk-accent-light); letter-spacing: 4px; margin: 0 0 12px; }
.result-score { font-family: 'JetBrains Mono', monospace; font-size: 3rem; font-weight: 700; color: var(--sk-gold); margin: 8px 0; }
.result-detail { color: var(--sk-text-dim); font-size: 0.95rem; margin-bottom: 18px; line-height: 1.6; }
#nickname { width: 100%; padding: 12px 14px; border-radius: 10px; background: var(--sk-bg); color: var(--sk-text); border: 1.5px solid var(--sk-surface-light); font-size: 0.95rem; margin-bottom: 12px; box-sizing: border-box; font-family: 'DM Sans', sans-serif; }
#nickname:focus { outline: none; border-color: var(--sk-accent); }
.result-actions { display: flex; gap: 10px; justify-content: center; margin-bottom: 10px; }
.lb-card h2 { font-family: 'Syne', sans-serif; color: var(--sk-accent-light); letter-spacing: 4px; margin-bottom: 18px; }
#leaderboard-list { list-style: none; padding: 0; margin: 0 0 16px; text-align: left; counter-reset: lb; }
#leaderboard-list li { counter-increment: lb; display: flex; justify-content: space-between; padding: 10px 14px; background: var(--sk-bg); margin-bottom: 6px; border-radius: 8px; border: 1px solid var(--sk-surface-light); }
#leaderboard-list li::before { content: counter(lb); color: var(--sk-accent-light); font-weight: 700; margin-right: 10px; min-width: 24px; }
#leaderboard-list li:nth-child(1) { border-color: var(--sk-gold); }
#leaderboard-list .lb-score { font-family: 'JetBrains Mono', monospace; color: var(--sk-accent-light); font-weight: 600; }
@media (max-width: 900px) {
    .sk-layout { flex-direction: column; padding: 12px; }
    .ad-slot { width: 100%; }
    .ad-placeholder--vertical { width: 100%; height: 90px; }
    .sk-tile { width: 36px; height: 36px; }
    .sk-tile .sk-piece { width: 30px; height: 30px; }
}