:root {
  --red: #FF2D55;
  --red-hot: #FF6B82;
  --red-deep: #c81e3a;
  --bg: #0B0B09;
  --raised: #12100d;
  --raised-2: #1b1813;
  --cream: #F0EDE6;
  --muted: #9c948a;
  --gold: #c9a84c;
  --line: #2a2620;
  --light-sq: #ece5d6;
  --dark-sq: #7a6a55;
  --sel: #ff2d5566;
  --last: #c9a84c55;
  --check: #ff2d5599;
  --ok: #4caf7d;
  --mono: 'IBM Plex Mono', ui-monospace, monospace;
  --display: 'Syne', system-ui, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; }
body {
  background: radial-gradient(1200px 600px at 70% -10%, #17140f 0%, var(--bg) 55%);
  color: var(--cream);
  font-family: system-ui, 'Segoe UI', Inter, sans-serif;
  min-height: 100%;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }

/* ---------- top bar ---------- */
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 22px; border-bottom: 1px solid var(--line);
  background: rgba(11,11,9,.7); backdrop-filter: blur(8px);
  position: sticky; top: 0; z-index: 30;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-mark { font-size: 26px; color: var(--red); filter: drop-shadow(0 0 10px #ff2d5566); }
.brand-word { font-family: var(--display); font-weight: 800; letter-spacing: .5px; font-size: 19px; }
.brand-accent { color: var(--red); }
.topnav { display: flex; gap: 18px; font-family: var(--mono); font-size: 13px; color: var(--muted); }
.topnav a:hover { color: var(--cream); }

main { flex: 1; width: 100%; }
.footsig { text-align: center; color: var(--muted); font-size: 12px; padding: 18px; font-family: var(--mono); }
.footsig a { color: var(--gold); }

/* ---------- home ---------- */
.home { max-width: 1000px; margin: 0 auto; padding: 40px 22px 60px; }
.hero { text-align: center; margin-bottom: 38px; }
.hero h1 { font-family: var(--display); font-weight: 800; font-size: clamp(34px, 6vw, 62px); line-height: 1; }
.hero h1 .g { color: var(--red); }
.hero p { color: var(--muted); margin-top: 14px; font-size: 16px; }

.panels { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 18px; }
.card {
  background: linear-gradient(180deg, var(--raised) 0%, var(--raised-2) 100%);
  border: 1px solid var(--line); border-radius: 16px; padding: 22px;
}
.card h2 { font-family: var(--display); font-weight: 700; font-size: 20px; margin-bottom: 6px; }
.card .sub { color: var(--muted); font-size: 13px; margin-bottom: 16px; }

.tc-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; margin-bottom: 16px; }
.tc {
  border: 1px solid var(--line); background: #0e0c08; border-radius: 10px;
  padding: 12px 6px; text-align: center; cursor: pointer; transition: .12s;
}
.tc:hover { border-color: var(--red); }
.tc.on { border-color: var(--red); background: #1a0d10; box-shadow: 0 0 0 1px var(--red) inset; }
.tc b { display: block; font-family: var(--mono); font-weight: 700; font-size: 18px; }
.tc span { color: var(--muted); font-size: 11px; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-family: var(--display); font-weight: 700; font-size: 15px;
  padding: 13px 18px; border-radius: 12px; border: 1px solid transparent;
  cursor: pointer; width: 100%; transition: .14s; background: var(--raised-2); color: var(--cream);
}
.btn:hover { transform: translateY(-1px); }
.btn.primary { background: linear-gradient(180deg, var(--red) 0%, var(--red-deep) 100%); color: #fff; box-shadow: 0 6px 22px #ff2d5533; }
.btn.ghost { background: transparent; border-color: var(--line); }
.btn.ghost:hover { border-color: var(--red); }
.btn.sm { width: auto; padding: 9px 14px; font-size: 13px; }
.btn:disabled { opacity: .5; cursor: default; transform: none; }

.seg { display: flex; gap: 8px; margin-bottom: 14px; }
.seg button {
  flex: 1; padding: 10px; border-radius: 10px; border: 1px solid var(--line);
  background: #0e0c08; color: var(--muted); cursor: pointer; font-family: var(--mono); font-size: 13px;
}
.seg button.on { color: #fff; border-color: var(--red); background: #1a0d10; }

.diff { display: flex; gap: 8px; margin-bottom: 14px; }
.diff button { flex: 1; padding: 9px; border-radius: 9px; border: 1px solid var(--line); background: #0e0c08; color: var(--muted); cursor: pointer; font-family: var(--mono); font-size: 12px; }
.diff button.on { color: #fff; border-color: var(--gold); }

/* ---------- game layout ---------- */
.game-wrap { max-width: 1120px; margin: 0 auto; padding: 22px; display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 24px; align-items: start; }
.board-col { display: flex; flex-direction: column; gap: 10px; }

.playerbar { display: flex; align-items: center; justify-content: space-between; padding: 4px 2px; }
.pname { display: flex; align-items: center; gap: 8px; font-weight: 600; }
.pdot { width: 9px; height: 9px; border-radius: 50%; background: var(--muted); }
.pdot.on { background: var(--ok); box-shadow: 0 0 8px var(--ok); }
.clock {
  font-family: var(--mono); font-weight: 700; font-size: 26px; letter-spacing: 1px;
  background: #0e0c08; border: 1px solid var(--line); border-radius: 10px; padding: 4px 14px; min-width: 108px; text-align: center;
}
.clock.active { border-color: var(--red); color: #fff; box-shadow: 0 0 0 1px var(--red) inset; }
.clock.low { color: var(--red-hot); }

/* board */
.board {
  width: min(72vh, 100%); aspect-ratio: 1; margin: 0 auto;
  display: grid; grid-template-columns: repeat(8, 1fr); grid-template-rows: repeat(8, 1fr);
  border-radius: 10px; overflow: hidden; border: 1px solid var(--line);
  box-shadow: 0 18px 60px rgba(0,0,0,.5); touch-action: none; user-select: none;
}
.sq { position: relative; display: flex; align-items: center; justify-content: center; }
.sq.light { background: var(--light-sq); }
.sq.dark { background: var(--dark-sq); }
.sq.last::after { content: ''; position: absolute; inset: 0; background: var(--last); }
.sq.sel::after { content: ''; position: absolute; inset: 0; background: var(--sel); }
.sq.check .piece { filter: drop-shadow(0 0 6px var(--red)); }
.sq .coord { position: absolute; font-size: 10px; font-family: var(--mono); opacity: .5; }
.sq .coord.file { bottom: 2px; right: 3px; }
.sq .coord.rank { top: 2px; left: 3px; }
.sq.light .coord { color: #6b5c46; }
.sq.dark .coord { color: #e6dcc8; }

.piece {
  font-size: min(9vh, 12vw); line-height: 1; cursor: grab; z-index: 2;
  position: relative; width: 100%; height: 100%;
  display: flex; align-items: center; justify-content: center;
}
.piece.dragging { cursor: grabbing; opacity: .35; }
.piece.w { color: #f7f4ec; text-shadow: 0 1px 0 #0007, 0 0 1px #000, 1px 0 0 #0006, -1px 0 0 #0006, 0 2px 4px #0009; }
.piece.b { color: #1a1712; text-shadow: 0 1px 0 #fff5, 0 2px 4px #0008; }
.hint { position: absolute; width: 30%; height: 30%; border-radius: 50%; background: #0003; z-index: 1; }
.sq.light .hint { background: #7a6a5555; }
.hint.cap { width: 100%; height: 100%; background: none; border-radius: 0; box-shadow: inset 0 0 0 6px #0002; }
.drag-ghost { position: fixed; pointer-events: none; z-index: 100; transform: translate(-50%, -50%); }

/* promotion */
.promo { position: absolute; inset: 0; background: #000a; display: flex; align-items: center; justify-content: center; z-index: 40; }
.promo-inner { display: flex; gap: 8px; background: var(--raised); padding: 14px; border-radius: 12px; border: 1px solid var(--red); }
.promo-inner .piece { font-size: 44px; cursor: pointer; width: 56px; height: 56px; border-radius: 8px; }
.promo-inner .piece:hover { background: #1a0d10; }

/* side panel */
.side { display: flex; flex-direction: column; gap: 16px; }
.box { background: var(--raised); border: 1px solid var(--line); border-radius: 14px; overflow: hidden; }
.box h3 { font-family: var(--mono); font-size: 11px; letter-spacing: 1px; text-transform: uppercase; color: var(--muted); padding: 12px 14px 0; }
.status-msg { padding: 12px 14px; font-family: var(--display); font-weight: 700; }
.status-msg .reason { font-family: system-ui; font-weight: 400; color: var(--muted); font-size: 13px; display: block; margin-top: 2px; }

.moves { max-height: 260px; overflow-y: auto; padding: 10px 12px; font-family: var(--mono); font-size: 13px; line-height: 1.9; }
.moves .mv { display: inline-block; min-width: 62px; padding: 1px 5px; border-radius: 4px; cursor: default; }
.moves .num { color: var(--muted); display: inline-block; min-width: 26px; }
.moves .mv.cur { background: var(--red); color: #fff; }

.actions { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; padding: 12px 14px; }
.actions .btn.sm { width: 100%; }

.share { padding: 12px 14px; display: flex; flex-direction: column; gap: 8px; }
.share .link { font-family: var(--mono); font-size: 12px; background: #0e0c08; border: 1px solid var(--line); border-radius: 8px; padding: 9px; word-break: break-all; color: var(--red-hot); }

.chat { display: flex; flex-direction: column; height: 220px; }
.chat-log { flex: 1; overflow-y: auto; padding: 10px 12px; font-size: 13px; display: flex; flex-direction: column; gap: 5px; }
.chat-log .cm { line-height: 1.35; }
.chat-log .cm b { color: var(--gold); font-weight: 600; }
.chat-log .cm.w b { color: var(--cream); }
.chat-log .cm.b b { color: var(--muted); }
.chat-in { display: flex; border-top: 1px solid var(--line); }
.chat-in input { flex: 1; background: transparent; border: 0; color: var(--cream); padding: 11px 12px; font-family: var(--mono); font-size: 13px; outline: none; }

.toast { position: fixed; bottom: 24px; left: 50%; transform: translateX(-50%); background: var(--raised); border: 1px solid var(--red); color: var(--cream); padding: 12px 18px; border-radius: 12px; font-family: var(--mono); font-size: 13px; z-index: 80; box-shadow: 0 10px 30px #000a; }
.banner { background: #1a0d10; border: 1px solid var(--red); border-radius: 10px; padding: 10px 12px; font-size: 13px; display: flex; align-items: center; justify-content: space-between; gap: 8px; }

/* watch/list */
.list { max-width: 720px; margin: 0 auto; padding: 30px 22px; }
.list h1 { font-family: var(--display); font-weight: 800; font-size: 30px; margin-bottom: 18px; }
.grow-row { display: flex; justify-content: space-between; padding: 12px 14px; border: 1px solid var(--line); border-radius: 10px; margin-bottom: 8px; background: var(--raised); font-family: var(--mono); font-size: 13px; }
.grow-row .res { color: var(--gold); }
.empty { color: var(--muted); text-align: center; padding: 40px; font-family: var(--mono); }

@media (max-width: 900px) {
  .game-wrap { grid-template-columns: 1fr; }
  .board { width: min(94vw, 72vh); }
  .side { order: 2; }
}