/* ============================================================
   星环防线 · UI 样式（暗色科幻主题）
   ============================================================ */
:root {
  --bg: #05070d;
  --panel: rgba(9, 15, 26, 0.93);
  --panel-solid: #0b1220;
  --line: rgba(88, 158, 214, 0.30);
  --line-soft: rgba(88, 158, 214, 0.14);
  --cyan: #4ad9ff;
  --magenta: #ff5fd0;
  --gold: #ffcf5c;
  --danger: #ff5a5a;
  --ok: #7cf06a;
  --text: #d6e6f5;
  --muted: #7d95ad;
  --radius: 10px;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.55);
  --font: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  -webkit-tap-highlight-color: transparent;
  -webkit-user-select: none;
  user-select: none;
}

#app { position: relative; width: 100vw; height: 100vh; overflow: hidden; }

#scene { display: block; width: 100%; height: 100%; touch-action: none; cursor: crosshair; }

/* 电影感暗角：只压边缘，不动画面中心，避免出现“栅格化”观感 */
#vignette {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 6;
  background: radial-gradient(ellipse at 50% 48%, rgba(0, 0, 0, 0) 58%, rgba(2, 4, 10, 0.42) 100%);
}

/* 基地受击红闪 */
#damage-flash {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 8;
  opacity: 0;
  background: radial-gradient(ellipse at center, rgba(255, 40, 60, 0) 32%, rgba(255, 30, 60, 0.55) 100%);
}

#damage-flash.on { animation: damageFlash 0.46s ease-out; }

@keyframes damageFlash {
  0% { opacity: 0.95; }
  100% { opacity: 0; }
}

.hidden { display: none !important; }

/* ---------------- 顶部数据 ---------------- */
#hud-top {
  position: absolute;
  top: 12px;
  left: 12px;
  display: flex;
  gap: 8px;
  align-items: stretch;
  pointer-events: none;
  flex-wrap: wrap;
  max-width: calc(100vw - 160px);
}

/* HUD 打击反馈：击杀 / Boss / 漏怪 */
#hud-top.hit { animation: hudHit 0.24s ease-out; }
#hud-top.hit-boss { animation: hudHitBoss 0.62s ease-out; }
#hud-top.hit-leak { animation: hudHitLeak 0.5s ease-out; }

@keyframes hudHit {
  0% { transform: scale(1.03); filter: brightness(1.5); }
  100% { transform: scale(1); filter: brightness(1); }
}

@keyframes hudHitBoss {
  0% { transform: scale(1.06); filter: brightness(2); }
  40% { transform: scale(1.02); filter: brightness(1.35); }
  100% { transform: scale(1); filter: brightness(1); }
}

@keyframes hudHitLeak {
  0% { transform: translateX(-4px); filter: brightness(1.7) saturate(1.7); }
  45% { transform: translateX(3px); }
  100% { transform: translateX(0); filter: brightness(1); }
}

.stat {
  position: relative;
  display: flex;
  align-items: center;
  gap: 6px;
  min-width: 72px;
  padding: 7px 11px 7px 13px;
  background: linear-gradient(180deg, rgba(19, 32, 50, 0.94), rgba(7, 12, 22, 0.94));
  border: 1px solid rgba(88, 158, 214, 0.32);
  border-radius: var(--radius);
  box-shadow: var(--shadow), inset 0 1px 0 rgba(150, 220, 255, 0.14), 0 0 20px rgba(20, 90, 140, 0.14);
  font-size: 14px;
  backdrop-filter: blur(8px);
  overflow: hidden;
}

.stat::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, transparent, var(--cyan), transparent);
  opacity: 0.7;
}

.stat .ico { color: var(--cyan); font-size: 13px; text-shadow: 0 0 10px currentColor; }
.stat b { font-variant-numeric: tabular-nums; font-weight: 600; letter-spacing: 0.4px; text-shadow: 0 0 12px currentColor; }

#stat-gold b { color: var(--gold); }
#stat-gold .ico { color: var(--gold); }
#stat-hp b { color: var(--ok); }
#stat-hp.low b { color: var(--danger); }
#stat-hp.low { border-color: rgba(255, 90, 90, 0.6); animation: pulse 1.2s infinite; }
#stat-enemy b { color: #ff9d9d; }
#stat-enemy .ico { color: #ff9d9d; }

.stat.phase {
  color: var(--muted);
  font-size: 12.5px;
  font-weight: 500;
  min-width: 0;
  gap: 7px;
}

.stat.phase::after {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 9px var(--cyan);
  animation: phasePulse 1.8s ease-in-out infinite;
}

@keyframes phasePulse { 50% { opacity: 0.35; transform: scale(0.8); } }

@keyframes pulse { 50% { border-color: rgba(255, 90, 90, 0.15); } }

/* ---------------- 右上设置 ---------------- */
#hud-top-right {
  position: absolute;
  top: 12px;
  right: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.volume {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 6px 11px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  font-size: 12px;
  color: var(--muted);
  backdrop-filter: blur(6px);
}

.volume .vol-ico { color: var(--cyan); font-size: 13px; }
.volume b { color: var(--text); font-size: 12px; min-width: 22px; text-align: right; font-variant-numeric: tabular-nums; }

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 92px;
  height: 4px;
  border-radius: 3px;
  background: rgba(88, 158, 214, 0.25);
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 8px rgba(74, 217, 255, 0.8);
  cursor: pointer;
}

input[type="range"]::-moz-range-thumb {
  width: 13px;
  height: 13px;
  border: none;
  border-radius: 50%;
  background: var(--cyan);
  cursor: pointer;
}

.icon-btn {
  width: 32px;
  height: 32px;
  border-radius: var(--radius);
  background: var(--panel);
  border: 1px solid var(--line);
  color: var(--cyan);
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: background 0.15s, color 0.15s;
}

.icon-btn:hover { background: rgba(74, 217, 255, 0.16); }

/* ---------------- 底部控制 ---------------- */
#hud-bottom {
  position: absolute;
  bottom: 14px;
  left: 12px;
  right: 12px;
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 12px;
  pointer-events: none;
}

#wave-control {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  pointer-events: auto;
}

button {
  font-family: var(--font);
  cursor: pointer;
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(22, 37, 58, 0.95), rgba(8, 14, 24, 0.95));
  color: var(--text);
  border-radius: var(--radius);
  font-size: 13px;
  padding: 9px 14px;
  box-shadow: inset 0 1px 0 rgba(150, 220, 255, 0.12), 0 6px 18px rgba(0, 0, 0, 0.35);
  transition: background 0.15s, border-color 0.15s, transform 0.08s, color 0.15s, box-shadow 0.15s;
  backdrop-filter: blur(6px);
}

button:hover:not(:disabled) {
  border-color: rgba(74, 217, 255, 0.55);
  color: #eaf8ff;
  transform: translateY(-1px);
  box-shadow: inset 0 1px 0 rgba(150, 220, 255, 0.2), 0 8px 22px rgba(0, 0, 0, 0.4), 0 0 18px rgba(74, 217, 255, 0.14);
}

button:active { transform: translateY(1px); }
button:disabled { opacity: 0.45; cursor: not-allowed; }

#btn-next-wave {
  position: relative;
  overflow: hidden;
  border-color: rgba(74, 217, 255, 0.55);
  background: linear-gradient(180deg, rgba(74, 217, 255, 0.24), rgba(74, 217, 255, 0.1));
  color: var(--cyan);
  font-weight: 600;
  box-shadow: 0 0 20px rgba(74, 217, 255, 0.2), inset 0 1px 0 rgba(200, 245, 255, 0.28);
}

#btn-next-wave::after {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  left: -60%;
  width: 38%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  transform: skewX(-18deg);
  animation: sheen 3.6s ease-in-out infinite;
  pointer-events: none;
}

#btn-ad-reward {
  border-color: rgba(255, 190, 92, 0.5);
  background: linear-gradient(180deg, rgba(255, 190, 92, 0.2), rgba(255, 140, 40, 0.08));
  color: #ffd79a;
  font-weight: 600;
}

#btn-ad-reward:hover:not(:disabled) {
  border-color: rgba(255, 214, 140, 0.8);
  color: #fff3dc;
  box-shadow: 0 0 18px rgba(255, 170, 60, 0.24), inset 0 1px 0 rgba(255, 240, 210, 0.28);
}

@keyframes sheen {
  0%, 62% { left: -60%; }
  100% { left: 130%; }
}

#btn-next-wave:hover:not(:disabled) { background: linear-gradient(180deg, rgba(74, 217, 255, 0.34), rgba(74, 217, 255, 0.16)); }
#btn-next-wave em { font-style: normal; color: var(--muted); margin-left: 6px; font-size: 12px; }
#btn-next-wave.running { border-color: rgba(255, 90, 90, 0.5); color: #ff9d9d; background: rgba(255, 90, 90, 0.12); }

#speed-group { display: flex; overflow: hidden; border-radius: var(--radius); box-shadow: var(--shadow); }
#speed-group button { border-radius: 0; border-right-width: 0; padding: 9px 11px; }
#speed-group button:first-child { border-radius: var(--radius) 0 0 var(--radius); }
#speed-group button:last-child { border-radius: 0 var(--radius) var(--radius) 0; border-right-width: 1px; }
#speed-group button.active { background: rgba(74, 217, 255, 0.24); color: var(--cyan); }

#btn-pause.active { background: rgba(255, 207, 92, 0.2); color: var(--gold); border-color: rgba(255, 207, 92, 0.5); }

/* ---------------- 技能栏 ---------------- */
#skills { display: flex; gap: 8px; pointer-events: auto; }

.skill {
  position: relative;
  width: 66px;
  height: 66px;
  padding: 0;
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  overflow: hidden;
  background: radial-gradient(circle at 50% 18%, rgba(74, 217, 255, 0.16), rgba(9, 15, 26, 0.96) 70%);
  box-shadow: inset 0 1px 0 rgba(150, 220, 255, 0.12), 0 8px 20px rgba(0, 0, 0, 0.4);
}

.skill:hover:not(:disabled) {
  border-color: rgba(74, 217, 255, 0.6);
  transform: translateY(-2px);
  box-shadow: inset 0 1px 0 rgba(150, 220, 255, 0.2), 0 10px 24px rgba(0, 0, 0, 0.5), 0 0 22px rgba(74, 217, 255, 0.22);
}

.skill .glyph { font-size: 20px; color: var(--cyan); line-height: 1; text-shadow: 0 0 12px rgba(74, 217, 255, 0.85); }
.skill .sname { font-size: 10.5px; color: var(--muted); }
.skill .scost { font-size: 10.5px; color: var(--gold); }
.skill .cd-mask {
  position: absolute;
  inset: 0;
  background: rgba(3, 6, 12, 0.72);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  font-weight: 600;
  color: #fff;
  font-variant-numeric: tabular-nums;
}
.skill.poor { border-color: rgba(255, 90, 90, 0.35); }
.skill.poor .scost { color: var(--danger); }
.skill.armed { border-color: var(--cyan); box-shadow: 0 0 0 1px var(--cyan), 0 0 20px rgba(74, 217, 255, 0.45); }

/* ---------------- 浮动面板 ---------------- */
.panel {
  position: absolute;
  background:
    radial-gradient(120% 90% at 50% -20%, rgba(74, 217, 255, 0.10), rgba(9, 15, 26, 0) 62%),
    var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: var(--shadow), inset 0 1px 0 rgba(150, 220, 255, 0.10), 0 0 42px rgba(20, 90, 140, 0.16);
  backdrop-filter: blur(10px);
  z-index: 30;
  min-width: 250px;
  overflow: hidden;
  animation: pop 0.16s ease-out;
}

.panel::before {
  content: '';
  position: absolute;
  top: 0;
  left: 12%;
  right: 12%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(120, 235, 255, 0.9), transparent);
  pointer-events: none;
}

.panel::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 46px;
  background: linear-gradient(180deg, rgba(74, 217, 255, 0.07), transparent);
  pointer-events: none;
}

@keyframes pop { from { opacity: 0; transform: translateY(6px) scale(0.98); } }

.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px 8px;
  border-bottom: 1px solid var(--line-soft);
}

.panel-head h3 { margin: 0; font-size: 14px; font-weight: 600; letter-spacing: 0.4px; }

.panel .close {
  border: none;
  background: transparent;
  color: var(--muted);
  font-size: 18px;
  line-height: 1;
  padding: 2px 6px;
  box-shadow: none;
}
.panel .close:hover { color: var(--text); }

/* 建造菜单 */
.tower-list { display: grid; grid-template-columns: 1fr 1fr; gap: 7px; padding: 10px; }

.tower-card {
  position: relative;
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 8px 9px 8px 11px;
  border-radius: var(--radius);
  border: 1px solid var(--line-soft);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.045), rgba(255, 255, 255, 0.012));
  cursor: pointer;
  text-align: left;
  overflow: hidden;
  transition: border-color 0.15s, background 0.15s, box-shadow 0.15s, transform 0.12s;
}

.tower-card::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--c, var(--cyan));
  box-shadow: 0 0 12px var(--c, var(--cyan));
  opacity: 0.55;
  transition: opacity 0.15s;
}

.tower-card:hover {
  border-color: var(--c, var(--line));
  background: rgba(74, 217, 255, 0.09);
  box-shadow: 0 0 18px -4px var(--c, var(--cyan));
  transform: translateY(-1px);
}

.tower-card:hover::before { opacity: 1; }
.tower-card.disabled { opacity: 0.42; cursor: not-allowed; transform: none; }

.tower-card .tc-glyph {
  width: 30px;
  height: 30px;
  flex: 0 0 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 700;
  border: 1px solid currentColor;
  background: rgba(8, 14, 24, 0.8);
  box-shadow: inset 0 0 12px -4px currentColor, 0 0 10px -3px currentColor;
  text-shadow: 0 0 10px currentColor;
}

.tower-card .tc-info { min-width: 0; }
.tower-card .tc-name { font-size: 12.5px; font-weight: 600; white-space: nowrap; }
.tower-card .tc-cost { font-size: 11px; color: var(--gold); margin-top: 1px; }
.tower-card .tc-desc { font-size: 10.5px; color: var(--muted); margin-top: 2px; line-height: 1.25; }

/* 塔详情 */
.tp-body { padding: 11px 12px 4px; }
.tp-level { font-size: 11.5px; color: var(--cyan); margin-bottom: 8px; letter-spacing: 0.5px; }

.tp-stats { display: grid; grid-template-columns: auto 1fr; gap: 4px 12px; font-size: 12px; }
.tp-stats .k { color: var(--muted); }
.tp-stats .v { text-align: right; font-variant-numeric: tabular-nums; }
.tp-stats .v.up { color: var(--ok); }

.tp-desc { font-size: 11px; color: var(--muted); margin-top: 9px; line-height: 1.4; }

.tp-actions { display: flex; gap: 8px; padding: 10px 12px 12px; }
.tp-actions button { flex: 1; padding: 9px 8px; font-size: 12.5px; font-weight: 600; }
#tp-upgrade { border-color: rgba(124, 240, 106, 0.5); color: var(--ok); background: rgba(124, 240, 106, 0.12); }
#tp-upgrade:hover:not(:disabled) { background: rgba(124, 240, 106, 0.22); }
#tp-sell { border-color: rgba(255, 207, 92, 0.45); color: var(--gold); background: rgba(255, 207, 92, 0.10); }
#tp-sell:hover:not(:disabled) { background: rgba(255, 207, 92, 0.2); }

/* ---------------- 波次横幅 ---------------- */
#wave-banner {
  position: absolute;
  top: 22%;
  left: 50%;
  transform: translateX(-50%);
  text-align: center;
  pointer-events: none;
  z-index: 20;
  animation: bannerIn 0.4s ease-out;
}

#wave-banner .wb-idx {
  display: block;
  font-size: 46px;
  font-weight: 800;
  letter-spacing: 3px;
  color: #fff;
  text-shadow: 0 0 26px rgba(74, 217, 255, 0.9), 0 0 60px rgba(74, 217, 255, 0.5);
}

#wave-banner .wb-label {
  display: block;
  margin-top: 4px;
  font-size: 15px;
  letter-spacing: 6px;
  color: var(--cyan);
  text-shadow: 0 0 14px rgba(74, 217, 255, 0.7);
}

#wave-banner.boss .wb-idx { color: #ffe3a3; text-shadow: 0 0 26px rgba(255, 90, 90, 0.95), 0 0 70px rgba(255, 90, 90, 0.6); }
#wave-banner.boss .wb-label { color: #ff9d9d; text-shadow: 0 0 14px rgba(255, 90, 90, 0.8); }

@keyframes bannerIn {
  from { opacity: 0; transform: translateX(-50%) scale(1.25); }
  to { opacity: 1; transform: translateX(-50%) scale(1); }
}

/* ---------------- 提示 ---------------- */
#toast {
  position: absolute;
  bottom: 108px;
  left: 50%;
  transform: translateX(-50%);
  padding: 8px 18px;
  border-radius: 999px;
  background: linear-gradient(180deg, rgba(19, 34, 54, 0.97), rgba(6, 11, 20, 0.97));
  border: 1px solid rgba(74, 217, 255, 0.45);
  color: #eaf8ff;
  font-size: 12.5px;
  letter-spacing: 0.3px;
  box-shadow: var(--shadow), 0 0 22px rgba(74, 217, 255, 0.18), inset 0 1px 0 rgba(150, 220, 255, 0.16);
  pointer-events: none;
  z-index: 25;
  animation: toastIn 0.2s ease-out;
}

@keyframes toastIn {
  from { opacity: 0; transform: translateX(-50%) translateY(8px) scale(0.96); }
}

/* ---------------- 覆盖层 ---------------- */
.overlay {
  position: absolute;
  inset: 0;
  background: rgba(3, 6, 12, 0.76);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 40;
  backdrop-filter: blur(3px);
  padding: 18px;
}

.result-card {
  position: relative;
  width: min(440px, 100%);
  padding: 28px 24px 24px;
  text-align: center;
  background:
    radial-gradient(120% 70% at 50% 0%, rgba(255, 90, 90, 0.13), rgba(8, 12, 22, 0) 58%),
    linear-gradient(180deg, rgba(16, 26, 42, 0.98), rgba(8, 12, 22, 0.98));
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow), inset 0 1px 0 rgba(150, 220, 255, 0.12), 0 0 60px rgba(20, 90, 140, 0.2);
  overflow: hidden;
  animation: pop 0.2s ease-out;
}

.result-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 15%;
  right: 15%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 120, 120, 0.9), transparent);
}

.result-card.win {
  background:
    radial-gradient(120% 70% at 50% 0%, rgba(124, 240, 106, 0.13), rgba(8, 12, 22, 0) 58%),
    linear-gradient(180deg, rgba(16, 26, 42, 0.98), rgba(8, 12, 22, 0.98));
}

.result-card.win::before { background: linear-gradient(90deg, transparent, rgba(140, 255, 140, 0.9), transparent); }

.result-card h2 { margin: 0 0 8px; font-size: 26px; letter-spacing: 2px; color: var(--danger); text-shadow: 0 0 24px rgba(255, 90, 90, 0.45); }
.result-card.win h2 { color: var(--ok); text-shadow: 0 0 26px rgba(124, 240, 106, 0.5); }
.result-card p {
  margin: 0 0 16px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.6;
}

/* 手机竖屏横屏提示 */
#rotate-gate { z-index: 60; }
#btn-rotate-skip {
  display: block;
  width: 100%;
  margin-top: 10px;
  padding: 8px;
  background: none;
  border: 0;
  box-shadow: none;
  color: var(--muted);
  font-size: 12.5px;
}
#btn-rotate-skip:hover { color: var(--text); }

#result-stats { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; margin-bottom: 20px; }
#result-stats .rs {
  padding: 9px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(74, 217, 255, 0.06), rgba(255, 255, 255, 0.02));
  box-shadow: inset 0 1px 0 rgba(150, 220, 255, 0.08);
}
#result-stats .rs-k { display: block; font-size: 11px; color: var(--muted); letter-spacing: 0.4px; }
#result-stats .rs-v {
  display: block;
  font-size: 18px;
  font-weight: 700;
  margin-top: 3px;
  font-variant-numeric: tabular-nums;
  color: var(--cyan);
  text-shadow: 0 0 16px rgba(74, 217, 255, 0.45);
}

button.primary {
  position: relative;
  overflow: hidden;
  padding: 11px 32px;
  font-size: 14px;
  font-weight: 600;
  color: #041018;
  background: linear-gradient(180deg, #8cecff, #35b7e8);
  border: none;
  border-radius: 999px;
  box-shadow: 0 6px 20px rgba(53, 183, 232, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.5);
}
button.primary::after {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  left: -60%;
  width: 40%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.55), transparent);
  transform: skewX(-18deg);
  animation: sheen 3s ease-in-out infinite;
  pointer-events: none;
}
button.primary:hover { filter: brightness(1.08); transform: translateY(-1px); }

.help-card { text-align: left; }
.help-card h2 { color: var(--cyan); text-align: center; }
.help-list { margin: 0 0 14px; padding-left: 18px; font-size: 13px; line-height: 1.85; color: var(--text); }
.help-list b { color: var(--cyan); font-weight: 600; }
.help-tip { font-size: 12px; color: var(--muted); line-height: 1.6; margin-bottom: 18px; }
.help-card button.primary { display: block; margin: 0 auto; }

.start-card { width: min(480px, 100%); }
.start-sub { text-align: center; margin-bottom: 14px; }
.start-card .help-list { margin-bottom: 20px; }
.start-tip { text-align: center; margin-bottom: 0; }

#file-hint .hint-code {
  margin: 0 0 16px;
  padding: 12px 14px;
  font: 12px/1.7 monospace;
  text-align: left;
  white-space: pre-wrap;
  word-break: break-all;
  color: var(--cyan);
  background: rgba(0, 0, 0, 0.42);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  user-select: all;
}

/* ---------------- 移动端 / 窄屏适配 ---------------- */
@media (max-width: 820px), (max-height: 560px) {
  #hud-top { top: 8px; left: 8px; gap: 5px; max-width: calc(100vw - 110px); }
  .stat { padding: 5px 8px; font-size: 12px; min-width: 56px; }
  .stat.phase { display: none; }
  #hud-top-right { top: 8px; right: 8px; }
  .volume { padding: 4px 8px; }
  input[type="range"] { width: 62px; }
  #hud-bottom { bottom: 8px; left: 8px; right: 8px; flex-direction: column-reverse; align-items: stretch; gap: 8px; }
  #wave-control { justify-content: center; }
  button { padding: 8px 11px; font-size: 12px; }
  #skills { justify-content: center; }
  .skill { width: 56px; height: 56px; }
  .skill .glyph { font-size: 17px; }
  .panel { left: 8px !important; right: 8px; width: auto !important; }
  .tower-list { grid-template-columns: 1fr 1fr; }
  #wave-banner .wb-idx { font-size: 34px; }
  #toast { bottom: 130px; font-size: 11.5px; }
}

/* ---------------- Canvas 2D UI 模式 ----------------
   TapTap 小游戏运行时无 DOM：界面全部由 CanvasUI 绘制，
   这里只隐藏原 DOM UI，保留 3D 场景画布。 */
body.canvas-ui #hud-top,
body.canvas-ui #hud-top-right,
body.canvas-ui #hud-bottom,
body.canvas-ui #build-menu,
body.canvas-ui #tower-panel,
body.canvas-ui #wave-banner,
body.canvas-ui #toast,
body.canvas-ui #start,
body.canvas-ui #result,
body.canvas-ui #help,
body.canvas-ui #file-hint,
body.canvas-ui #vignette,
body.canvas-ui #damage-flash {
  display: none !important;
}