/* ============================================================
   水墨五子棋 · Ink Gomoku
   宣纸 / 墨色 / 朱砂
   ============================================================ */

:root {
  --paper: #f3ecda;        /* 宣纸黄 */
  --paper-2: #f8f3e6;      /* 亮纸 */
  --paper-3: #e9e1cd;      /* 暗纸 */
  --ink: #2f2a26;          /* 浓墨 */
  --ink-soft: #5c554d;     /* 淡墨 */
  --ink-faint: #9a9284;    /* 极淡墨 */
  --cinnabar: #b03a2e;     /* 朱砂 */
  --kai: "Kaiti SC", "STKaiti", "KaiTi", "华文楷体", "楷体", "Songti SC", serif;
  --serif: "Songti SC", "Noto Serif SC", "Source Han Serif SC", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --grain: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.5'/%3E%3C/svg%3E");
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html, body { height: 100%; }

body {
  font-family: var(--serif);
  color: var(--ink);
  background:
    linear-gradient(160deg, var(--paper-2) 0%, var(--paper) 45%, var(--paper-3) 100%);
  background-attachment: fixed;
  overflow-x: hidden;
}

/* 宣纸噪点 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background-image: var(--grain);
  opacity: 0.16;
  pointer-events: none;
  z-index: 0;
}

.view { position: relative; z-index: 1; min-height: 100vh; }
.hidden { display: none !important; }

/* ==================== 全局水墨背景 ==================== */
.bg-ink {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0.95;
}
.bg-ink svg {
  width: 100%;
  height: 100%;
  display: block;
}

/* ==================== 首页 ==================== */
#home {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 60px 24px 90px;
  text-align: center;
}

.home-kicker {
  font-family: var(--kai);
  font-size: 15px;
  letter-spacing: 14px;
  color: var(--ink-soft);
  margin-bottom: 18px;
  text-indent: 14px;
}

.home-title {
  font-family: var(--kai);
  font-size: clamp(64px, 12vw, 118px);
  font-weight: 700;
  letter-spacing: 20px;
  text-indent: 20px;
  color: var(--ink);
  line-height: 1.15;
  text-shadow: 0 2px 0 rgba(255, 255, 255, 0.5);
}

.home-sub {
  margin-top: 22px;
  font-size: 15px;
  letter-spacing: 6px;
  color: var(--ink-faint);
}

/* 模式菜单 */
.menu {
  margin-top: 64px;
  display: flex;
  flex-direction: column;
  gap: 26px;
  align-items: center;
}

.ink-btn {
  position: relative;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  min-width: 260px;
  padding: 18px 44px;
  background: transparent;
  border: 2px solid var(--ink);
  font-family: var(--kai);
  color: var(--ink);
  cursor: pointer;
  box-shadow: 5px 5px 0 rgba(47, 42, 38, 0.35);
  transition: all 0.22s ease;
  overflow: hidden;
}
.ink-btn::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--ink);
  transform: translateY(101%);
  transition: transform 0.28s ease;
}
.ink-btn:hover::before { transform: translateY(0); }
.ink-btn:hover {
  color: #ffffff;
  box-shadow: 3px 3px 0 rgba(47, 42, 38, 0.5);
  transform: translate(-1px, -1px);
}
.ink-btn:active {
  transform: translate(3px, 3px);
  box-shadow: 1px 1px 0 rgba(47, 42, 38, 0.5);
}

.ink-btn .btn-cn { position: relative; z-index: 1; font-size: 26px; letter-spacing: 10px; text-indent: 10px; }
.ink-btn .btn-en { position: relative; z-index: 1; font-size: 11px; letter-spacing: 3px; color: var(--ink-faint); }
.ink-btn:hover .btn-en { color: rgba(255, 255, 255, 0.72); }

.ink-btn.small {
  min-width: 0;
  flex-direction: row;
  padding: 9px 18px;
  font-size: 15px;
  letter-spacing: 3px;
  box-shadow: 3px 3px 0 rgba(47, 42, 38, 0.35);
}

/* 快捷键键帽提示 */
.ink-btn kbd {
  font-family: var(--mono, "SF Mono", Consolas, "Courier New", monospace);
  font-size: 11px;
  letter-spacing: 1px;
  border: 1px solid currentColor;
  border-bottom-width: 2px;
  border-radius: 4px;
  padding: 1px 7px;
  margin-left: 8px;
  opacity: 0.7;
  white-space: nowrap;
}
.ink-btn.small kbd { margin-left: 4px; }

.home-foot {
  position: fixed;
  bottom: 26px;
  left: 0;
  right: 0;
  text-align: center;
  font-size: 12px;
  letter-spacing: 3px;
  color: var(--ink-faint);
  z-index: 2;
}

/* ==================== 游戏页 ==================== */
#game {
  display: flex;
  flex-direction: column;
  align-items: center;
  min-height: 100vh;
  padding: 24px 20px 48px;
}

.game-header {
  width: 100%;
  max-width: 720px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.game-title {
  font-family: var(--kai);
  font-size: 24px;
  letter-spacing: 6px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.mode-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink);
  box-shadow: 0 0 0 3px rgba(47, 42, 38, 0.15);
}

.game-status {
  margin: 26px 0 18px;
  padding: 10px 30px;
  border: 1.5px solid var(--ink);
  font-family: var(--kai);
  font-size: 20px;
  letter-spacing: 6px;
  background: rgba(248, 243, 230, 0.6);
  box-shadow: 3px 3px 0 rgba(47, 42, 38, 0.25);
  min-width: 220px;
  text-align: center;
}
.game-status.black-turn { color: var(--ink); }
.game-status.white-turn { color: var(--ink-soft); }
.game-status.win { color: var(--cinnabar); border-color: var(--cinnabar); }
.game-status.paused { color: var(--ink-faint); border-style: dashed; }

/* 状态行 + 倒计时 */
.status-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin: 26px 0 18px;
  flex-wrap: wrap;
}
.clock {
  font-family: var(--mono, "SF Mono", Consolas, "Courier New", monospace);
  font-size: 26px;
  letter-spacing: 2px;
  color: var(--ink);
  border: 1.5px solid var(--ink);
  background: rgba(248, 243, 230, 0.6);
  padding: 6px 18px;
  box-shadow: 3px 3px 0 rgba(47, 42, 38, 0.25);
  min-width: 78px;
  text-align: center;
}
.clock.danger {
  color: var(--cinnabar);
  border-color: var(--cinnabar);
  animation: clockBlink 0.6s ease infinite alternate;
}
@keyframes clockBlink {
  from { opacity: 1; }
  to { opacity: 0.45; }
}

.board-wrap {
  position: relative;
  width: 100%;
  max-width: 780px;
  background: var(--paper-2);
  border: 2px solid var(--ink);
  padding: 12px;
  box-shadow: 8px 8px 0 rgba(47, 42, 38, 0.28),
              inset 0 0 24px rgba(47, 42, 38, 0.06);
}

#board {
  display: block;
  width: 100%;
  height: auto;
  cursor: pointer;
  background: var(--paper-2);
}

/* 特效层（落子动画 / 神之一手特效） */
#fx {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

/* 工具栏（神之一手 / 悔棋） */
.toolbar {
  display: flex;
  gap: 14px;
  margin: 14px 0 16px;
  align-items: center;
}
.toolbar .ink-btn.small { font-size: 14px; letter-spacing: 2px; padding: 8px 16px; }

.game-hint {
  margin-top: 20px;
  font-size: 13px;
  letter-spacing: 3px;
  color: var(--ink-faint);
}

/* ==================== 单人模式 · AI 难度三档 ==================== */
.menu-ai { margin-top: 34px; gap: 18px; }
.menu-ai-title {
  font-size: 14px;
  letter-spacing: 5px;
  color: var(--ink-faint);
}
.menu-ai-row {
  display: flex;
  gap: 18px;
  justify-content: center;
  flex-wrap: wrap;
}
.menu-ai-row .ink-btn {
  min-width: 0;
  width: 200px;
  padding: 14px 18px;
}
.menu-ai-row .btn-cn { font-size: 23px; letter-spacing: 8px; text-indent: 8px; }

/* ==================== 胜利横幅 ==================== */
.victory {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 50;
  font-family: var(--kai);
  font-size: clamp(44px, 8vw, 84px);
  font-weight: 700;
  letter-spacing: 18px;
  text-indent: 18px;
  color: var(--ink);
  background: rgba(248, 243, 230, 0.88);
  border: 3px solid var(--ink);
  padding: 26px 64px;
  box-shadow: 10px 10px 0 rgba(47, 42, 38, 0.3);
  pointer-events: none;
  text-align: center;
}
.victory.pop { animation: victoryPop 2.2s ease forwards; }
@keyframes victoryPop {
  0% { opacity: 0; transform: translate(-50%, -50%) scale(0.6); }
  12% { opacity: 1; transform: translate(-50%, -50%) scale(1.08); }
  20% { transform: translate(-50%, -50%) scale(1); }
  82% { opacity: 1; }
  100% { opacity: 0; transform: translate(-50%, -50%) scale(1.02); }
}

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
  .ink-btn { min-width: 220px; }
  .ink-btn .btn-cn { font-size: 22px; letter-spacing: 8px; text-indent: 8px; }
  .home-title { letter-spacing: 12px; text-indent: 12px; }
  .game-title { font-size: 18px; letter-spacing: 3px; }
  .ink-btn.small { padding: 8px 12px; font-size: 13px; letter-spacing: 2px; }
  .game-status { font-size: 16px; letter-spacing: 4px; padding: 8px 18px; }
}