/* =========================================================
   高智商人机五子棋 - 墨水屏(E-ink)高对比度极简风格
   ========================================================= */

/* 禁用一切动画与过渡，防止墨水屏刷新残影 */
*, *::before, *::after {
  box-sizing: border-box;
  -webkit-animation: none !important;
  animation: none !important;
  -webkit-transition: none !important;
  transition: none !important;
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
}

:root {
  --bg: #ffffff;
  --fg: #000000;
  --panel: #e8e8e8;
  --panel-border: #9a9a9a;
  --btn-face: #dcdcdc;
  --accent: #000000;
}

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--fg);
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  overflow: hidden;
  -webkit-user-select: none;
  user-select: none;
  touch-action: manipulation;
}

#app {
  height: 100vh;
  height: 100dvh;
  display: flex;
  flex-direction: column;
}

/* ============ 顶部栏 ============ */
#topbar {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: var(--panel);
  border-bottom: 3px solid var(--fg);
  font-weight: bold;
}

.player {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 20px;
}

.player .mark {
  font-size: 12px;
  line-height: 1;
  display: none;
  color: #000;
}

.player.active .mark { display: inline; }
.player.active { color: var(--fg); }
.player:not(.active) { color: #808080; }
.player .mark { font-weight: normal; }

/* 顶部棋子 */
.stone {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  display: inline-block;
  border: 2px solid #000;
}
.stone.black { background: #111; }
.stone.white { background: #ffffff; }

.score {
  font-size: 26px;
  letter-spacing: 4px;
  color: var(--fg);
}

/* ============ 棋盘区 ============ */
#board-wrap {
  position: relative;
  flex: 1 1 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 6px;
  min-height: 0;
  width: 100%;
}

canvas#board {
  display: block;
  background: #f2ecd8;
  border: 3px solid var(--fg);
  touch-action: none;                        /* 交给 JS 处理，禁用页面滚动缩放 */
  -webkit-user-select: none;
  -webkit-touch-callout: none;               /* 长按不出系统菜单，提升触控落子流畅 */
  max-width: 98%;
  max-height: 100%;
  width: auto;
  height: auto;
}

#status-bar {
  margin-top: 8px;
  font-size: 18px;
  color: var(--fg);
  padding: 6px 18px;
  border: 2px solid var(--fg);
  background: #fff;
  text-align: center;
  letter-spacing: 1px;
}

/* 终局状态：反色高对比横幅，强化输赢辨识（墨水屏黑底白字） */
#status-bar.game-over {
  background: #000000;
  color: #ffffff;
  font-weight: bold;
  border-width: 3px;
  font-size: 20px;
}

/* ============ 底部工具栏 ============ */
#toolbar {
  flex: 0 0 auto;
  display: flex;
  gap: 8px;
  padding: 12px 10px calc(12px + env(safe-area-inset-bottom));
  background: var(--panel);
  border-top: 3px solid var(--fg);
}

.tool-btn {
  flex: 1;
  height: 74px;
  font-size: 26px;
  font-weight: bold;
  color: var(--fg);
  background: var(--btn-face);
  border: 3px solid var(--fg);
  border-radius: 10px;
  cursor: pointer;
  box-shadow: 0 4px 0 #000;
}

.tool-btn:active {
  background: #ffffff;
  box-shadow: 0 1px 0 #000;
  -webkit-transform: translateY(3px);
  transform: translateY(3px);
}

/* ============ 覆盖层 ============ */
#overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 20px;
}
#overlay.hidden { display: none; }

#overlay-box {
  background: #fff;
  border: 3px solid var(--fg);
  border-radius: 12px;
  padding: 22px;
  max-width: 90%;
  width: 420px;
  text-align: center;
  max-height: 90vh;
  overflow-y: auto;
}
#overlay-box h2 {
  margin: 0 0 10px;
  font-size: 26px;
}
#overlay-box p {
  margin: 6px 0 16px;
  font-size: 18px;
  line-height: 1.6;
  text-align: left;
  color: #111;
}
#choice-row { display: flex; gap: 10px; justify-content: center; margin-bottom: 14px; }
#choice-row button,
#ov-close {
  flex: 1;
  padding: 14px 0;
  font-size: 22px;
  font-weight: bold;
  color: var(--fg);
  background: var(--btn-face);
  border: 3px solid var(--fg);
  border-radius: 8px;
  cursor: pointer;
}
#ov-close { flex: 1; width: 100%; margin-top: 2px; }
#choice-row button:active, #ov-close:active { background: #fff; }

/* ============ 设置面板 ============ */
.setting-group {
  margin-bottom: 20px;
  text-align: left;
}
.setting-group h3 {
  margin: 0 0 10px;
  font-size: 20px;
  border-bottom: 2px solid var(--fg);
  padding-bottom: 4px;
}
.seg-row {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}
.seg {
  flex: 1;
  min-width: 46px;
  padding: 12px 4px;
  font-size: 19px;
  font-weight: bold;
  text-align: center;
  background: var(--btn-face);
  border: 3px solid var(--fg);
  border-radius: 8px;
  cursor: pointer;
  color: var(--fg);
}
.seg.active {
  background: var(--fg);
  color: #fff;
}
.seg.disabled {
  opacity: 0.35;
  cursor: default;
}
/* 设置面板提示行 */
.hint {
  margin-top: 6px;
  font-size: 15px;
  color: #333;
  text-align: center;
}
.switch-label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 19px;
  padding: 4px 0;
  cursor: pointer;
}
.switch {
  width: 74px;
  height: 40px;
  border: 3px solid var(--fg);
  border-radius: 22px;
  background: #fff;
  position: relative;
  cursor: pointer;
}
.switch::after {
  content: "";
  position: absolute;
  top: 2px;
  left: 2px;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: #bbb;
  border: 2px solid var(--fg);
}
.switch.on { background: var(--fg); }
.switch.on::after { left: 38px; background: #fff; }

#about-text {
  font-size: 16px;
  line-height: 1.7;
  color: #111;
}
#about-text b { display: block; margin-bottom: 6px; }