/* ==========================================================================
   贪吃蛇 · 页面样式
   ========================================================================== */

.game-shell {
  max-width: 1180px;
  margin: 0 auto;
  padding: 28px 24px 60px;
}

.game-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  gap: 22px;
  align-items: start;
}

.board-zone { min-width: 0; }

.status-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 12px 18px;
  margin-bottom: 14px;
  font-size: 14.5px;
  min-height: 50px;
}

.led {
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 5px 12px;
}

.led b { color: var(--accent); }

.status-text { color: var(--text); font-weight: 600; margin-left: auto; }

.ai-badge {
  color: #0c240f;
  background: linear-gradient(120deg, #7ce8a2, #34d374);
  border-radius: 999px;
  padding: 4px 12px;
  font-size: 12.5px;
  font-weight: 700;
  animation: aiPulse 1.2s ease-in-out infinite;
}

@keyframes aiPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

/* ---------- 画布 ---------- */
.board-wrap { display: flex; justify-content: center; position: relative; }

#board {
  width: min(520px, 100%);
  aspect-ratio: 1 / 1;
  display: block;
  background: linear-gradient(160deg, #2b3040, #1d2230);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  touch-action: none;
}

/* 待开始遮罩（不拦截点击，点透到画布触发开局） */
.start-hint {
  position: absolute;
  inset: 0;
  margin: auto;
  width: fit-content;
  height: fit-content;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  background: rgba(10, 12, 17, 0.62);
  border: 1px solid rgba(245, 176, 74, 0.35);
  border-radius: 16px;
  padding: 18px 26px;
  text-align: center;
  pointer-events: none;
  animation: hintFloat 2.4s ease-in-out infinite;
  backdrop-filter: blur(3px);
  -webkit-backdrop-filter: blur(3px);
}

.start-hint.hidden { display: none; }

.start-hint-icon { font-size: 34px; line-height: 1; }

.start-hint p {
  margin: 0;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--text);
}

.start-hint b { color: var(--accent); }

@keyframes hintFloat {
  0%, 100% { transform: translateY(0); opacity: 0.95; }
  50% { transform: translateY(-5px); opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  .start-hint { animation: none; }
}

/* ---------- 侧栏 ---------- */
.panel {
  display: flex;
  flex-direction: column;
  gap: 16px;
  position: sticky;
  top: 84px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}

.card.grow { flex: 1; }

.card-title {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--text-dim);
  margin-bottom: 16px;
}

.field { margin-bottom: 14px; }

.field label {
  display: block;
  font-size: 13.5px;
  font-weight: 600;
  margin-bottom: 8px;
}

.field .hint { color: var(--text-faint); font-weight: 400; font-size: 12px; }

.field-note {
  font-size: 12px;
  color: var(--text-faint);
  margin-top: 8px;
  line-height: 1.6;
}

.segmented {
  display: flex;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 4px;
  gap: 4px;
}

.segmented button {
  flex: 1;
  font-family: var(--font);
  font-size: 12.5px;
  font-weight: 600;
  color: var(--text-faint);
  background: transparent;
  border: none;
  border-radius: 9px;
  padding: 8px 4px;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.segmented button:hover { color: var(--text-dim); }

.segmented button.on {
  color: var(--text);
  background: var(--surface-2);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.35), 0 0 0 1px rgba(245, 176, 74, 0.25) inset;
}

.btn-row { display: flex; gap: 10px; }

.btn-row .btn { flex: 1; padding: 10px 6px; font-size: 13px; }

.btn-row .btn.primary { background: var(--gradient); }

.keys-grid {
  display: grid;
  grid-template-columns: repeat(3, 44px);
  gap: 6px;
  justify-content: center;
  margin: 4px 0 12px;
}

.keys-grid kbd {
  display: grid;
  place-items: center;
  height: 36px;
  background: var(--surface-2);
  border: 1px solid var(--border-strong);
  border-radius: 9px;
  font-family: var(--font);
  font-size: 14px;
  font-weight: 700;
  color: var(--text-dim);
  box-shadow: 0 2px 0 rgba(0, 0, 0, 0.4);
}

/* ---------- 弹窗 / Toast ---------- */
.overlay {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: rgba(6, 8, 12, 0.7);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: grid;
  place-items: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s;
}

.overlay.show { opacity: 1; pointer-events: auto; }

.dialog {
  width: min(420px, calc(100vw - 40px));
  background: linear-gradient(165deg, var(--surface), var(--surface-2));
  border: 1px solid var(--border-strong);
  border-radius: 22px;
  padding: 36px 32px 30px;
  text-align: center;
  box-shadow: 0 40px 90px -20px rgba(0, 0, 0, 0.8);
  transform: translateY(14px) scale(0.96);
  transition: transform 0.3s cubic-bezier(0.2, 0.7, 0.3, 1.2);
}

.overlay.show .dialog { transform: translateY(0) scale(1); }

.dialog-icon { font-size: 52px; line-height: 1; margin-bottom: 14px; }

.dialog h2 { font-size: 24px; font-weight: 800; }

.dialog > p { color: var(--text-dim); font-size: 14.5px; margin-top: 8px; }

.dialog-btns { display: flex; gap: 12px; margin-top: 26px; justify-content: center; }

.rules-body { text-align: left; margin-top: 14px; display: flex; flex-direction: column; gap: 10px; }

.rules-body p { font-size: 13.5px; color: var(--text-dim); line-height: 1.7; }

.rules-body b { color: var(--text); }

.toast {
  position: fixed;
  left: 50%;
  bottom: 34px;
  transform: translate(-50%, 20px);
  background: var(--surface-2);
  border: 1px solid var(--border-strong);
  color: var(--text);
  font-size: 14px;
  font-weight: 600;
  padding: 11px 22px;
  border-radius: 999px;
  box-shadow: 0 14px 40px rgba(0, 0, 0, 0.5);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s, transform 0.25s;
  z-index: 400;
}

.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .game-layout { grid-template-columns: 1fr; }
  .panel { position: static; }
  .game-shell { padding: 20px 14px 48px; }
}