/* ============================================================
   apps/connect-four.html 样式（深色玻璃拟态 + 蓝金霓虹风）
   视觉对齐 2026-09-12 升级后的 gobang.html/point24.html。
   ============================================================ */

/* Design Token：项目级 Glassmorphism 规范（与 topbar.8d4aa38f.css 一致） */
:root {
  --glass-bg-light:           rgba(255, 255, 255, 0.55);
  --glass-border-light:        rgba(15, 23, 42, 0.06);
  --glass-highlight-light:     rgba(255, 255, 255, 0.6);
  --glass-shadow-light:        rgba(15, 23, 42, 0.06);
  --glass-bg-dark:             rgba(10, 14, 39, 0.72);
  --glass-border-dark:         rgba(255, 255, 255, 0.06);
  --glass-highlight-dark:      rgba(255, 255, 255, 0.08);
  --glass-shadow-dark:         rgba(0, 0, 0, 0.32);
  --glass-blur:                blur(20px) saturate(180%);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
/* body 用 min-height（而非 height:100%）：让 body 高度随内容增长，保证 sticky 顶栏全程有效 */
html { height: 100%; }
body { min-height: 100%; }

:root {
  --bg-deep:     #0f172a;
  --bg-page:     #0f172a;
  --bg-card:     rgba(30, 41, 59, 0.72);
  --bg-card-solid: #1e293b;
  --bg-inner:    rgba(15, 23, 42, 0.55);
  --text-primary:   #e2e8f0;
  --text-secondary: #94a3b8;
  --text-muted:     #64748b;
  --text-hint:      #475569;
  --text-on-accent: #ffffff;
  --border:      rgba(148, 163, 184, 0.18);
  --border-soft: rgba(148, 163, 184, 0.10);

  /* 蓝金霓虹主色 */
  --accent:        #3b82f6;
  --accent-hover:  #2563eb;
  --accent-soft:   #60a5fa;
  --accent-fade:   rgba(59, 130, 246, 0.14);
  --blue-glow:     rgba(59, 130, 246, 0.45);
  --gold:        #f59e0b;
  --gold-2:      #fbbf24;
  --gold-dark:   #d97706;
  --gold-bg:     rgba(245, 158, 11, 0.12);
  --gold-border: rgba(251, 191, 36, 0.55);
  --gold-glow:   rgba(245, 158, 11, 0.35);

  --success:     #34d399;
  --warning:     #fbbf24;
  --danger:      #f87171;
  --shadow:      0 10px 30px rgba(0, 0, 0, 0.45);
  --shadow-neon: 0 0 0 1px rgba(59, 130, 246, 0.35), 0 0 28px rgba(59, 130, 246, 0.22);
  --shadow-gold: 0 0 0 1px rgba(251, 191, 36, 0.45), 0 0 28px rgba(245, 158, 11, 0.25);
  --shadow-red:  0 0 0 1px rgba(248, 113, 113, 0.45), 0 0 28px rgba(248, 113, 113, 0.25);

  /* 棋盘 / 玻璃 */
  --board-bg:        rgba(15, 23, 42, 0.65);
  --board-border:    rgba(148, 163, 184, 0.22);
  --board-hole:      rgba(0, 0, 0, 0.42);
  --stone-blue-1:    #60a5fa;
  --stone-blue-2:    #1d4ed8;
  --stone-gold-1:    #fde68a;
  --stone-gold-2:    #b45309;
}

body {
  background:
    radial-gradient(ellipse 75% 55% at 50% -5%, rgba(59, 130, 246, 0.22) 0%, transparent 60%),
    radial-gradient(ellipse 45% 40% at 100% 100%, rgba(245, 158, 11, 0.10) 0%, transparent 60%),
    radial-gradient(ellipse 40% 35% at 0% 80%, rgba(37, 99, 235, 0.10) 0%, transparent 60%),
    var(--bg-deep);
  color: var(--text-primary);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }

/* ============== 漂浮粒子 ============== */
.cf-particles { position: fixed; inset: 0; z-index: 0; pointer-events: none; overflow: hidden; }
.cf-particles span {
  position: fixed;
  bottom: -8vh;
  font-weight: 700;
  opacity: 0;
  animation-name: cf-float;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
  user-select: none;
}
@keyframes cf-float {
  0%   { transform: translateY(0) rotate(0deg); opacity: 0; }
  12%  { opacity: 0.5; }
  88%  { opacity: 0.5; }
  100% { transform: translateY(-118vh) rotate(360deg); opacity: 0; }
}

/* ============== 通用容器 ============== */
main {
  flex: 1;
  position: relative;
  z-index: 1;
  padding: 28px 40px 80px;
  max-width: 1080px;
  width: 100%;
  margin: 0 auto;
}

/* ============== Hero ============== */
.cf-head {
  text-align: center;
  margin-bottom: 22px;
}
.cf-head h1 {
  font-size: clamp(26px, 8.2vw, 38px);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-wrap: balance;
  background: linear-gradient(90deg, var(--accent-soft), var(--gold-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 0 24px rgba(59, 130, 246, 0.18);
  margin-bottom: 8px;
}
.cf-head .sub {
  color: var(--text-secondary);
  font-size: 14px;
  letter-spacing: 0.06em;
}

/* ============== 先手选择 ============== */
.cf-side-row {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin: 18px auto 22px;
}
.cf-side-btn {
  padding: 9px 18px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-secondary);
  font-size: 13px;
  letter-spacing: 0.06em;
  cursor: pointer;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  transition: all 0.18s ease;
}
.cf-side-btn:hover {
  color: var(--text-primary);
  border-color: var(--accent-soft);
}
.cf-side-btn.active {
  color: var(--text-on-accent);
  background: linear-gradient(135deg, rgba(59,130,246,0.55), rgba(37,99,235,0.55));
  border-color: var(--accent-soft);
  box-shadow: var(--shadow-neon);
}
.cf-side-btn.active.gold {
  background: linear-gradient(135deg, rgba(245,158,11,0.55), rgba(217,119,6,0.55));
  border-color: var(--gold-2);
  box-shadow: var(--shadow-gold);
}

/* ============== 游戏区 ============== */
.cf-game {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 28px;
  align-items: flex-start;
}
@media (max-width: 880px) {
  .cf-game { grid-template-columns: 1fr; }
}

/* ============== 棋盘 ============== */
.cf-board-wrap {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 18px;
  border-radius: 18px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  transition: box-shadow 0.4s ease;
}
.cf-board-wrap.thinking { box-shadow: var(--shadow-neon); }
.cf-board-wrap.stage-win  { box-shadow: var(--shadow-gold); }
.cf-board-wrap.stage-lose { box-shadow: var(--shadow-red); }
.cf-board-wrap.stage-draw { box-shadow: 0 0 0 1px rgba(148,163,184,0.35), 0 0 28px rgba(148,163,184,0.18); }

.cf-col-hint {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 6px;
}
.cf-col-hint-cell {
  height: 26px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  color: var(--text-muted);
  background: rgba(15,23,42,0.4);
  border: 1px solid var(--border-soft);
  cursor: pointer;
  user-select: none;
  transition: all 0.15s ease;
}
.cf-col-hint-cell:hover:not(.disabled) {
  color: var(--accent-soft);
  border-color: var(--accent-soft);
  background: rgba(59,130,246,0.10);
}
.cf-col-hint-cell.disabled { opacity: 0.35; cursor: not-allowed; }

.cf-board {
  position: relative;
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 6px;
  padding: 14px;
  border-radius: 14px;
  background: var(--board-bg);
  border: 1px solid var(--board-border);
  box-shadow: inset 0 0 0 1px rgba(148,163,184,0.06), inset 0 8px 22px rgba(0,0,0,0.35);
}

.cf-cell {
  position: relative;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: var(--board-hole);
  box-shadow: inset 0 4px 8px rgba(0,0,0,0.55), inset 0 -2px 4px rgba(255,255,255,0.04);
  display: flex;
  align-items: center;
  justify-content: center;
}

.cf-stone {
  position: absolute;
  inset: 6%;
  border-radius: 50%;
  background: radial-gradient(circle at 32% 28%, var(--stone-blue-1) 0%, var(--stone-blue-2) 80%);
  box-shadow: 0 4px 10px rgba(0,0,0,0.45), inset 0 -3px 6px rgba(0,0,0,0.35);
  animation: cf-drop 0.42s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.cf-stone.ai {
  background: radial-gradient(circle at 32% 28%, var(--stone-gold-1) 0%, var(--stone-gold-2) 80%);
  box-shadow: 0 4px 10px rgba(0,0,0,0.45), inset 0 -3px 6px rgba(0,0,0,0.35), 0 0 14px rgba(245,158,11,0.35);
}
.cf-stone.last {
  outline: 2px solid var(--gold-2);
  outline-offset: 3px;
  box-shadow: var(--shadow-gold), inset 0 -3px 6px rgba(0,0,0,0.35);
}
.cf-stone.win {
  outline: 3px solid var(--danger);
  outline-offset: 2px;
  box-shadow: var(--shadow-red), inset 0 -3px 6px rgba(0,0,0,0.35);
}
@keyframes cf-drop {
  0%   { transform: translateY(-260%); opacity: 0.4; }
  60%  { opacity: 1; }
  100% { transform: translateY(0);     opacity: 1; }
}

.cf-status {
  text-align: center;
  font-size: 13px;
  color: var(--text-secondary);
  letter-spacing: 0.06em;
  min-height: 22px;
}
.cf-status.win  { color: var(--gold-2); }
.cf-status.lose { color: var(--danger); }
.cf-status.draw { color: var(--text-muted); }

/* ============== 侧栏 ============== */
.cf-panel {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.cf-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}
.cf-stat-card {
  padding: 14px 16px;
  border-radius: 14px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
.cf-stat-card .l { color: var(--text-muted); font-size: 11px; letter-spacing: 0.1em; text-transform: uppercase; }
.cf-stat-card .v { color: var(--text-primary); font-size: 22px; font-weight: 700; letter-spacing: 0.04em; margin-top: 4px; }
.cf-stat-card .v small { font-size: 12px; color: var(--text-muted); margin-left: 4px; font-weight: 500; }
.cf-stat-card.is-time .v { color: var(--accent-soft); }
.cf-stat-card.is-best .v { color: var(--gold-2); }

.cf-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 14px;
  border-radius: 14px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
.cf-btn {
  flex: 1 1 auto;
  min-width: 90px;
  padding: 9px 14px;
  border-radius: 999px;
  background: rgba(15,23,42,0.45);
  color: var(--text-secondary);
  font-size: 12px;
  letter-spacing: 0.06em;
  border: 1px solid var(--border);
  cursor: pointer;
  transition: all 0.18s ease;
}
.cf-btn:hover:not(:disabled) {
  color: var(--text-primary);
  border-color: var(--accent-soft);
}
.cf-btn:disabled { opacity: 0.35; cursor: not-allowed; }
.cf-btn.primary {
  background: linear-gradient(135deg, rgba(59,130,246,0.55), rgba(37,99,235,0.55));
  color: var(--text-on-accent);
  border-color: var(--accent-soft);
  box-shadow: var(--shadow-neon);
}
.cf-btn.primary:hover:not(:disabled) { box-shadow: 0 0 0 1px rgba(59,130,246,0.55), 0 0 36px rgba(59,130,246,0.30); }
.cf-btn.danger { color: var(--danger); }
.cf-btn.danger:hover:not(:disabled) { border-color: var(--danger); }

.cf-status-info {
  padding: 12px 16px;
  border-radius: 14px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 12px;
  letter-spacing: 0.04em;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
.cf-status-info .guest { color: var(--text-hint); }

/* ============== Modal ============== */
.cf-modal-mask {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.75);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 100;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}
.cf-modal-mask.show { display: flex; }
.cf-modal {
  width: min(420px, 92vw);
  padding: 28px 26px 22px;
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(30,41,59,0.92), rgba(15,23,42,0.92));
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  text-align: center;
}
.cf-modal h2 {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: 0.06em;
  margin-bottom: 6px;
}
.cf-modal h2.win  { color: var(--gold-2); text-shadow: 0 0 18px rgba(245,158,11,0.35); }
.cf-modal h2.lose { color: var(--danger); text-shadow: 0 0 18px rgba(248,113,113,0.35); }
.cf-modal h2.draw { color: var(--text-primary); }
.cf-modal .sub { color: var(--text-secondary); font-size: 13px; margin-bottom: 18px; }
.cf-modal .result {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 18px;
}
.cf-modal .r {
  padding: 10px 6px;
  border-radius: 12px;
  background: rgba(15,23,42,0.55);
  border: 1px solid var(--border-soft);
}
.cf-modal .r .l { color: var(--text-muted); font-size: 10px; letter-spacing: 0.1em; text-transform: uppercase; }
.cf-modal .r .v { color: var(--text-primary); font-size: 16px; font-weight: 700; margin-top: 4px; }
.cf-modal .actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
}
.cf-badge {
  display: inline-block;
  margin-bottom: 14px;
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--gold-bg);
  color: var(--gold-2);
  border: 1px solid var(--gold-border);
  font-size: 12px;
  letter-spacing: 0.06em;
}
.cf-badge.guest {
  background: rgba(148,163,184,0.10);
  color: var(--text-muted);
  border-color: var(--border);
}

/* ============== Toast ============== */
.cf-toast {
  position: fixed;
  left: 50%;
  bottom: 60px;
  transform: translateX(-50%);
  padding: 10px 18px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.92);
  border: 1px solid var(--border);
  color: var(--text-primary);
  font-size: 13px;
  letter-spacing: 0.04em;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 200;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
.cf-toast.show { opacity: 1; transform: translateX(-50%) translateY(-6px); }
.cf-toast.error { color: var(--danger); border-color: var(--danger); }
.cf-toast.success { color: var(--success); border-color: var(--success); }

/* ============== Back link ============== */
.cf-back-wrap {
  position: relative;
  z-index: 1;
  padding: 18px 40px 0;
  max-width: 1080px;
  margin: 0 auto;
  width: 100%;
}
.cf-back {
  display: inline-block;
  color: var(--text-secondary);
  font-size: 13px;
  letter-spacing: 0.06em;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
.cf-back:hover { color: var(--accent-soft); border-color: var(--accent-soft); }

/* ============== Topbar 适配（深色玻璃 + 霓虹；统一方案 A） ==============
   顶栏统一化：原深色玻璃 !important 覆盖块（含 dead 的 .wordmark .mark 规则）
   已删除，严格使用共享 topbar 样式。 */