:root {
  --bg: #f3f1ec; --card: #fff; --ink: #222; --muted: #777; --line: #e3dfd6;
  --accent: #2f6fed; --x: #d62f2f; --o: #1f6fd6; --win: #ffe27a; --good: #1a9a4a;
  --board: #e9c98b; --grid: #b8935a;
}
@media (prefers-color-scheme: dark) {
  :root { --bg:#16181c; --card:#1f2228; --ink:#e8e8e8; --muted:#9aa0a8; --line:#33373f;
    --board:#6b5532; --grid:#4a3a21; --win:#7a6a1a; --x:#ff6b6b; --o:#6aa8ff; }
}
* { box-sizing: border-box; }
body { margin:0; font-family: system-ui, -apple-system, "Segoe UI", sans-serif; background:var(--bg); color:var(--ink); }
.top { display:flex; justify-content:space-between; align-items:center; padding:12px 20px; gap:10px; flex-wrap:wrap; }
.top h1 { margin:0; font-size:22px; }
main { padding: 0 16px 32px; max-width:1300px; margin:0 auto; }
.card { background:var(--card); border:1px solid var(--line); border-radius:12px; padding:16px; }
.narrow { max-width:720px; margin:0 auto; }
h2 { margin-top:0; }
button, select, input { font:inherit; }
button { border:1px solid var(--line); background:var(--card); color:var(--ink); padding:6px 12px; border-radius:8px; cursor:pointer; }
button:hover:not(:disabled) { border-color:var(--accent); }
button:disabled { opacity:.5; cursor:default; }
button.primary { background:var(--accent); color:#fff; border-color:var(--accent); padding:8px 18px; }
button.danger { color:#c33; }
input, select { padding:5px 8px; border:1px solid var(--line); border-radius:6px; background:var(--card); color:var(--ink); }
.form-grid { display:grid; grid-template-columns:repeat(auto-fit,minmax(150px,1fr)); gap:12px; }
.form-grid label { display:flex; flex-direction:column; gap:4px; font-size:14px; }
.hint { color:var(--muted); font-size:13px; }
#nameInputs { display:grid; grid-template-columns:repeat(auto-fit,minmax(240px,1fr)); gap:12px; margin:12px 0 16px; }
fieldset { border:1px solid var(--line); border-radius:8px; }
fieldset .row { display:flex; gap:6px; align-items:center; margin:4px 0; }
fieldset .row input[type=text] { flex:1; min-width:0; }
fieldset .row label { font-size:13px; white-space:nowrap; }

.layout { display:grid; grid-template-columns: minmax(320px, 620px) 1fr; gap:16px; align-items:start; }
@media (max-width: 960px) { .layout { grid-template-columns:1fr; } }

.match-info { text-align:center; margin-bottom:10px; min-height:48px; }
.match-info .vs { font-size:18px; font-weight:600; }
.match-info .status { color:var(--muted); font-size:14px; margin-top:2px; }
.x { color:var(--x); } .o { color:var(--o); }
.board { display:grid; background:var(--board); border:2px solid var(--grid); width:100%; max-width:600px; margin:0 auto; user-select:none; }
.cell { aspect-ratio:1; border:1px solid var(--grid); display:flex; align-items:center; justify-content:center;
  font-weight:700; cursor:pointer; line-height:1; container-type:size; }
.cell span { font-size:70cqmin; }
.cell:hover:not(.taken) { background:rgba(255,255,255,.3); }
.cell.taken { cursor:default; }
.cell.X { color:var(--x); } .cell.O { color:var(--o); }
.cell.last { box-shadow: inset 0 0 0 2px var(--accent); }
.cell.win { background:var(--win); }
.board-actions { display:flex; justify-content:center; gap:8px; margin-top:10px; }

.tabs { display:flex; gap:6px; margin-bottom:12px; }
.tabs button.active { background:var(--accent); color:#fff; border-color:var(--accent); }
.group-block { margin-bottom:20px; }
.group-block h3 { margin:0 0 6px; }
table { width:100%; border-collapse:collapse; font-size:14px; }
th, td { padding:6px 8px; text-align:center; border-bottom:1px solid var(--line); }
th { color:var(--muted); font-weight:600; font-size:12px; }
td.name, th.name { text-align:left; }
tr.qual td:first-child { box-shadow: inset 3px 0 0 var(--good); }
td.pts { font-weight:700; }
.bot-tag { font-size:11px; color:var(--muted); border:1px solid var(--line); border-radius:4px; padding:0 4px; margin-left:4px; }
.legend { color:var(--muted); font-size:12px; margin-top:4px; }

.filters { display:flex; gap:12px; margin-bottom:10px; flex-wrap:wrap; }
.filters label { font-size:14px; display:flex; gap:6px; align-items:center; }
.round-title { font-weight:700; margin:14px 0 6px; padding-bottom:4px; border-bottom:2px solid var(--line); }
.match { display:grid; grid-template-columns: 70px 1fr auto auto; gap:8px; align-items:center; padding:6px 8px; border-radius:8px; border:1px solid transparent; }
.match:nth-child(even) { background:rgba(128,128,128,.06); }
.match.active { border-color:var(--accent); }
.match .tag { font-size:12px; color:var(--muted); }
.match .teams { display:flex; gap:8px; align-items:center; flex-wrap:wrap; }
.match .teams b.w { color:var(--good); }
.match .score { font-weight:700; min-width:48px; text-align:center; }
.match .leg { font-size:11px; color:var(--muted); }

.actions { display:flex; align-items:center; gap:10px; flex-wrap:wrap; }
.actions .me { font-size:14px; display:flex; gap:6px; align-items:center; }
.conn { width:10px; height:10px; border-radius:50%; background:#c33; display:inline-block; }
.conn.on { background:var(--good); }
.match .btns { display:flex; gap:4px; }

.match-info .series { font-size:14px; margin-top:2px; }

.board-wrap { overflow:auto; max-height:80vh; }

.undo-box { display:inline-flex; gap:6px; align-items:center; flex-wrap:wrap; font-size:14px; }
.board-actions { flex-wrap:wrap; align-items:center; }

.cell.block { background:repeating-linear-gradient(45deg,rgba(0,0,0,.35) 0 4px,rgba(0,0,0,.15) 4px 8px); cursor:not-allowed; }
.cell.block span { font-size:60cqmin; }
.cell.allowed { background:rgba(26,154,74,.45); }

/* đồng hồ */
.clocks { display:flex; gap:10px; justify-content:center; margin-bottom:8px; }
.clock { display:flex; justify-content:space-between; align-items:center; gap:12px; min-width:150px; padding:6px 12px; border:2px solid var(--line); border-radius:10px; opacity:.65; }
.clock b { font-size:22px; font-variant-numeric:tabular-nums; }
.clock.running { opacity:1; border-color:var(--accent); box-shadow:0 0 0 3px rgba(47,111,237,.2); }
.clock.low b { color:#d62f2f; }
.clock.low.running { animation:blink 1s steps(2) infinite; }
.clock.out { border-color:#d62f2f; }
@keyframes blink { 50% { background:rgba(214,47,47,.15); } }
.f-form { display:flex; flex-wrap:wrap; gap:10px; align-items:flex-end; margin:10px 0 14px; }
.f-form label { font-size:14px; display:flex; flex-direction:column; gap:4px; }
#btnFriendlyMode { margin-left:8px; }

[hidden] { display:none !important; }

/* tạm dừng */
.board-stage { position:relative; }
.board-stage.paused .board-wrap { filter:blur(7px) grayscale(.4); opacity:.45; pointer-events:none; user-select:none; transition:filter .25s, opacity .25s; }
.pause-overlay { position:absolute; inset:0; display:flex; align-items:center; justify-content:center; font-size:32px; font-weight:700; z-index:2; pointer-events:none; text-shadow:0 2px 12px rgba(0,0,0,.4); }