/* Sokoban — dark neon theme */
:root {
    --bg: #0d1321; --bg2: #121c30; --card: #1a2235; --border: #1e2a45;
    --cyan: #4fc3f7; --purple: #ab47bc; --gold: #ffd700;
    --text: #e6e9ef; --text-dim: #8892a8; --danger: #ff6b6b; --success: #4cd137;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
    font-family: -apple-system, "Segoe UI", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
    background: linear-gradient(135deg, #0d1321 0%, #1a1f3a 100%);
    color: var(--text); min-height: 100vh;
}
.navbar { background: linear-gradient(135deg, #0d1321 0%, #1a1f3a 100%); border-bottom: 1px solid var(--border); padding: 0.8rem 0; }
.nav-inner { max-width: 1200px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; padding: 0 2rem; }
.nav-brand { font-size: 1.3rem; font-weight: 700; background: linear-gradient(135deg, #4fc3f7, #ab47bc); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.nav-links-box { display: flex; align-items: center; gap: 1.5rem; }
.nav-links-box a { color: var(--text-dim); font-weight: 500; font-size: .95rem; text-decoration: none; }
.nav-links-box a:hover { color: var(--cyan); }
#lang-toggle { background: none; border: 1px solid var(--cyan); color: var(--cyan); padding: 4px 12px; border-radius: 6px; cursor: pointer; font-size: .85rem; }
#lang-menu { display: none; position: fixed; top: 70px; right: 20px; background: #141d2e; border: 1px solid var(--border); border-radius: 10px; padding: 8px 0; z-index: 300; box-shadow: 0 4px 20px rgba(0,0,0,.5); }
#lang-menu a { display: block; padding: 8px 20px; color: var(--text-dim); text-decoration: none; font-size: .9rem; }
#lang-menu a:hover { color: var(--cyan); background: rgba(79,195,247,.1); }

#game-area { display: flex; justify-content: center; padding: 1.2rem 1rem; }
#game-container { width: 100%; max-width: 500px; background: var(--card); border: 1px solid var(--border); border-radius: 16px; padding: 1rem; box-shadow: 0 8px 30px rgba(0,0,0,.45); }
#canvas-wrapper { position: relative; }
#sokobanCanvas { width: 100%; display: block; border-radius: 10px; touch-action: none; }

/* HUD */
#hud { display: flex; justify-content: space-between; align-items: center; padding: .5rem .25rem .25rem; font-size: .9rem; color: var(--text); }
#toolbar { display: flex; gap: .5rem; padding: .4rem 0; }
.chip { background: transparent; color: var(--text-dim); border: 1px solid var(--border); padding: .4rem .8rem; border-radius: 8px; cursor: pointer; font-size: .85rem; transition: all .15s; }
.chip:hover { color: var(--cyan); border-color: var(--cyan); }

/* 移动端虚拟方向键 */
#mobile-controls { display: flex; justify-content: center; padding: .6rem 0 0; }
.dpad { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 4px; width: 168px; }
.dpad .cb { display: flex; align-items: center; justify-content: center; width: 52px; height: 44px; background: var(--bg2); border: 1px solid var(--border); border-radius: 10px; color: var(--cyan); font-size: 1.1rem; user-select: none; -webkit-user-select: none; }
.dpad .cb:active { background: var(--cyan); color: #0d1321; }
#btn-up { margin: 0 auto; grid-column: 2; }
.dpad-mid { grid-column: 1 / 4; display: flex; gap: 4px; justify-content: center; }

/* Overlay */
.overlay { position: absolute; inset: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: .7rem; background: rgba(10,14,26,0.86); border-radius: 10px; text-align: center; padding: 1.5rem; z-index: 20; }
.overlay h1 { font-size: 1.7rem; }
.controls-hint { font-size: .85rem; color: var(--text-dim); }
.overlay button, #startBtn { background: linear-gradient(135deg, #4fc3f7, #ab47bc); color: #fff; border: none; padding: .7rem 1.6rem; border-radius: 10px; font-size: 1rem; cursor: pointer; font-weight: 600; transition: transform .1s; }
.overlay button:hover, #startBtn:hover { transform: translateY(-2px); }
.overlay button.secondary { background: transparent; border: 1px solid var(--cyan); color: var(--cyan); }
.btn-row { display: flex; gap: .6rem; }
.hidden { display: none !important; }

/* 选关面板 */
.panel { position: absolute; inset: 0; background: rgba(10,14,26,0.92); border-radius: 10px; padding: 1.2rem; z-index: 30; display: flex; flex-direction: column; }
.panel-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: .8rem; font-size: 1.1rem; font-weight: 600; }
#level-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: .5rem; overflow-y: auto; }
.level-btn { aspect-ratio: 1; background: var(--bg2); color: var(--text); border: 1px solid var(--border); border-radius: 10px; font-size: .95rem; cursor: pointer; }
.level-btn:hover:not(:disabled) { border-color: var(--cyan); color: var(--cyan); }
.level-btn.current { border-color: var(--gold); color: var(--gold); }
.level-btn:disabled { color: var(--text-dim); opacity: .55; cursor: not-allowed; }

.toast { position: absolute; top: 12px; left: 50%; transform: translateX(-50%); background: rgba(255,90,90,.92); color: #fff; padding: .5rem 1rem; border-radius: 8px; font-size: .85rem; z-index: 40; }

.seo-section { max-width: 720px; margin: 2rem auto; padding: 0 1.2rem 3rem; }
.seo-card { background: var(--card); border: 1px solid var(--border); border-radius: 16px; padding: 1.6rem 2rem; }
.seo-card h2 { font-size: 1.4rem; margin-bottom: .8rem; color: var(--cyan); }
.seo-card h3 { font-size: 1.1rem; margin: 1.1rem 0 .5rem; color: var(--purple); }
.seo-card p, .seo-card li { color: var(--text-dim); line-height: 1.7; font-size: .95rem; }
.seo-card ul { padding-left: 1.3rem; margin: .4rem 0; }

@media (max-width: 600px) {
    .nav-inner { padding: 0 1rem; }
    #game-area { padding: .8rem .5rem; }
}