:root {
  --bg: #efe6d6;
  --paper: #fbf5ea;
  --ink: #2b211a;
  --muted: #7a6a58;
  --wood: #5a3b1e;
  --board: #e9cf9c;
  --board-line: #5a3b1e;
  --red: #b8332a;
  --black: #1f1a17;
  --disc: #f7ecd3;
  --accent: #2f6f4e;
  --warn: #a33;
  --radius: 12px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #1b1713; --paper: #26201b; --ink: #efe6d6; --muted: #b7a48c; --board: #d9bd87; }
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg); color: var(--ink);
  font: 15px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
}
a { color: var(--accent); }

.top { display: flex; align-items: baseline; gap: 14px; padding: 14px 20px 6px; flex-wrap: wrap; }
.top h1 { margin: 0; font-size: 22px; letter-spacing: .08em; font-family: "KaiTi", "STKaiti", "Kaiti SC", "Noto Serif SC", serif; }
.top .sub { color: var(--muted); font-size: 13px; }

.layout { display: grid; grid-template-columns: minmax(280px, 62vh) minmax(260px, 380px); gap: 20px; padding: 8px 20px 20px; justify-content: center; align-items: start; }
@media (max-width: 760px) { .layout { grid-template-columns: 1fr; padding: 4px 10px 16px; } }

.board-wrap { position: relative; }
.board { width: 100%; height: auto; display: block; border-radius: var(--radius); box-shadow: 0 6px 24px rgba(0,0,0,.18); user-select: none; -webkit-tap-highlight-color: transparent; }
.board .bg { fill: var(--board); }
.board .frame { fill: none; stroke: var(--board-line); stroke-width: 3; }
.board .grid, .board .mark { stroke: var(--board-line); fill: none; stroke-linecap: square; }
.board .mark { stroke-width: 3; }
.board .river { font-family: "KaiTi", "STKaiti", "Kaiti SC", "Noto Serif SC", serif; font-size: 52px; fill: var(--board-line); text-anchor: middle; dominant-baseline: central; opacity: .75; letter-spacing: .3em; }
.board .coord { font-size: 30px; fill: var(--board-line); text-anchor: middle; opacity: .7; }
.board .hit { fill: transparent; cursor: pointer; }
.board .last { fill: rgba(47, 111, 78, .22); }
.board .selected { fill: none; stroke: #2f6f4e; stroke-width: 6; }
.board .target { fill: rgba(47, 111, 78, .55); }
.board .target.capture { fill: none; stroke: rgba(184, 51, 42, .8); stroke-width: 6; stroke-dasharray: 14 10; }
.board .piece .disc { fill: var(--disc); stroke: #8a6a3a; stroke-width: 2; filter: drop-shadow(0 3px 2px rgba(0,0,0,.35)); }
.board .piece .ring { fill: none; stroke-width: 3; }
.board .piece .glyph { font-family: "KaiTi", "STKaiti", "Kaiti SC", "Noto Serif SC", serif; font-size: 54px; font-weight: 700; text-anchor: middle; dominant-baseline: central; }
.board .piece.red .ring, .board .piece.red .glyph { stroke: var(--red); fill: var(--red); }
.board .piece.red .ring { fill: none; }
.board .piece.black .ring, .board .piece.black .glyph { stroke: var(--black); fill: var(--black); }
.board .piece.black .ring { fill: none; }
.board .piece.check .disc { stroke: #e03; stroke-width: 6; filter: drop-shadow(0 0 10px rgba(230, 0, 50, .8)); }

.loader { position: absolute; inset: auto 12px 12px 12px; background: rgba(251, 245, 234, .95); color: #2b211a; border-radius: 10px; padding: 10px 14px; font-size: 13px; box-shadow: 0 4px 14px rgba(0,0,0,.2); }
.loader progress { width: 100%; height: 8px; }
.loader.done { display: none; }
.loader.error { background: #fde8e6; color: #7a1a12; }

.panel { background: var(--paper); border-radius: var(--radius); padding: 14px 16px; box-shadow: 0 2px 10px rgba(0,0,0,.08); display: flex; flex-direction: column; gap: 10px; min-height: 0; }
.status { font-size: 17px; font-weight: 600; min-height: 1.6em; }
.status.thinking { color: var(--muted); }
.status.over { color: var(--red); }
.status.warn { color: var(--warn); font-weight: 500; font-size: 14px; }
.think { font-size: 12px; color: var(--muted); min-height: 1.4em; font-variant-numeric: tabular-nums; }

.controls { display: grid; grid-template-columns: 1fr 1fr; gap: 8px 12px; align-items: center; font-size: 14px; }
.controls label { display: flex; align-items: center; gap: 6px; white-space: nowrap; }
.controls select { flex: 1; min-width: 0; font: inherit; padding: 5px 6px; border-radius: 8px; border: 1px solid #c9b79a; background: #fff; color: #222; }
.tag { font-size: 12px; color: var(--accent); }

.buttons { display: flex; flex-wrap: wrap; gap: 8px; }
button { font: inherit; padding: 8px 14px; border-radius: 10px; border: 1px solid #c9b79a; background: #fff; color: #222; cursor: pointer; }
button:hover:not(:disabled) { border-color: var(--wood); }
button:disabled { opacity: .5; cursor: default; }
button.primary { background: var(--wood); color: #fff; border-color: var(--wood); }

.moves-wrap { max-height: 300px; overflow: auto; border: 1px solid #e3d6bf; border-radius: 8px; background: #fff; color: #222; }
@media (max-width: 760px) { .moves-wrap { max-height: 180px; } }
.moves { width: 100%; border-collapse: collapse; font-size: 14px; font-variant-numeric: tabular-nums; }
.moves td { padding: 3px 8px; border-bottom: 1px solid #f0e8d8; }
.moves td.n { color: #999; width: 2.5em; text-align: right; }
.moves td.empty { color: #999; text-align: center; padding: 14px; }
.moves sup { color: var(--red); font-size: 10px; margin-left: 2px; }

.help { font-size: 13px; color: var(--muted); }
.help summary { cursor: pointer; }
.help ul { padding-left: 18px; margin: 6px 0 0; }

.foot { text-align: center; color: var(--muted); font-size: 12px; padding: 6px 12px 18px; }