/* 棋弈 · Swiss minimal: white / black (inverted in dark), one accent #FF4F00, sans only, 8px grid, 1px hairlines, radius 0–4px */
:root { color-scheme: light dark; }
:root[data-theme="light"] { color-scheme: light; }
:root[data-theme="dark"] { color-scheme: dark; }
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; -webkit-font-smoothing: antialiased; overflow-x: hidden; }
b, strong { font-weight: 700; }
[hidden] { display: none !important; }
h1, h2, h3 { margin: 0; }
svg { flex: none; }

:root {
  --x-accent: #ff4f00;
  --x-ink: light-dark(#000000, #ffffff);
  --x-bg: light-dark(#ffffff, #000000);
  --x-mute: light-dark(#595959, #a6a6a6);
  --x-hair: light-dark(#0000001f, #ffffff2e);
  --x-off: light-dark(#f0f0f0, #1a1a1a);
  --x-board: var(--x-bg);
  --x-line: light-dark(#000000, #ffffff);
  --x-sq-l: light-dark(#ffffff, #000000);
  --x-sq-d: light-dark(#d6d6d6, #3d3d3d);
  --x-ease: cubic-bezier(0.2, 0, 0, 1);
  --x-fast: 150ms; --x-mid: 200ms; --x-slow: 220ms;
  --x-font: "Geist", "Helvetica Neue", Helvetica, Arial, "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --x-mono: "Geist Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --x-tabh: 56px;
  --x-safe-b: env(safe-area-inset-bottom, 0px);
  --x-safe-t: env(safe-area-inset-top, 0px);
}
body { background: var(--x-bg); color: var(--x-ink); font-family: var(--x-font); overscroll-behavior-y: none; -webkit-tap-highlight-color: transparent; }
body button, body input { font-family: var(--x-font); }
:focus-visible { outline: 2px solid var(--x-accent); outline-offset: 2px; }
button { -webkit-user-select: none; user-select: none; }

/* ---------- shell ---------- */
.x-app {
  max-width: 560px; margin: 0 auto; min-height: 100dvh;
  padding: calc(16px + var(--x-safe-t)) max(16px, env(safe-area-inset-right)) calc(var(--x-tabh) + 32px + var(--x-safe-b)) max(16px, env(safe-area-inset-left));
}
.x-screen { display: none; }
.x-screen.is-on { display: block; animation: x-in var(--x-mid) var(--x-ease); }
@keyframes x-in { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

.x-eyebrow { margin: 0; font: 600 12px/16px var(--x-font); letter-spacing: .08em; text-transform: uppercase; color: var(--x-mute); }
.x-sec { margin: 40px 0 8px; font: 600 12px/16px var(--x-font); letter-spacing: .08em; text-transform: uppercase; color: var(--x-mute); }
.x-sec--first { margin-top: 0; }
.x-note { margin: 24px 0 0; font: 400 13px/20px var(--x-font); color: var(--x-mute); }
.x-link { color: inherit; text-underline-offset: 4px; }

/* home */
.x-head { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 44px; }
.x-chip {
  display: inline-flex; align-items: center; gap: 8px; min-height: 44px; max-width: 60%; padding: 0 16px 0 4px; border: 1px solid var(--x-ink);
  border-radius: 2px; background: none; color: inherit; cursor: pointer; font: 600 14px/20px var(--x-font);
  transition: transform var(--x-fast) var(--x-ease), background var(--x-fast) var(--x-ease);
}
.x-chip.is-guest { padding: 0 16px; }
.x-chip__t { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.x-chip:hover { background: var(--x-off); }
.x-hero { padding: 24px 0 32px; border-bottom: 1px solid var(--x-ink); }
.x-hero h1 { font: 700 72px/72px var(--x-font); letter-spacing: -0.05em; }
.x-hero p { margin: 16px 0 0; color: var(--x-mute); font: 500 16px/24px var(--x-font); }

.x-quick { display: grid; grid-template-columns: repeat(2, 1fr); border-left: 1px solid var(--x-ink); margin-top: 24px; }
.x-quick button {
  display: grid; grid-template-columns: 28px 1fr; grid-template-rows: auto auto; column-gap: 12px; align-items: center; text-align: left;
  min-height: 72px; padding: 16px; background: none; color: inherit; cursor: pointer;
  border: 0; border-right: 1px solid var(--x-ink); border-top: 1px solid var(--x-ink); border-bottom: 1px solid var(--x-ink); margin-bottom: -1px; border-radius: 0;
  transition: background var(--x-fast) var(--x-ease), transform var(--x-fast) var(--x-ease);
}
.x-quick svg { grid-row: 1 / 3; width: 28px; height: 28px; fill: none; stroke: currentColor; stroke-width: 1.75; stroke-linecap: round; stroke-linejoin: round; transition: stroke var(--x-fast) var(--x-ease); }
.x-quick b { font: 700 16px/24px var(--x-font); }
.x-quick span { font: 400 12px/16px var(--x-font); color: var(--x-mute); }
.x-quick button:hover { background: var(--x-off); }
.x-quick button:hover svg, .x-quick button:focus-visible svg { stroke: var(--x-accent); }

.x-cards { display: grid; border-top: 1px solid var(--x-ink); }
.x-card {
  display: flex; align-items: center; gap: 16px; width: 100%; text-align: left; color: inherit; cursor: pointer;
  background: none; border: 0; border-bottom: 1px solid var(--x-ink); border-radius: 0; padding: 16px 0; min-height: 88px;
  transition: transform var(--x-fast) var(--x-ease);
}
.x-card .x-grow { flex: 1; min-width: 0; }
.x-num { flex: none; min-width: 56px; font: 700 40px/40px var(--x-font); letter-spacing: -0.04em; font-variant-numeric: tabular-nums; transition: color var(--x-fast) var(--x-ease); }
.x-card:hover .x-num, .x-card:focus-visible .x-num { color: var(--x-accent); }
.x-card .x-h { display: block; font: 700 24px/32px var(--x-font); letter-spacing: -0.03em; }
.x-en { display: block; font: 600 12px/16px var(--x-font); letter-spacing: .08em; text-transform: uppercase; color: var(--x-mute); }
.x-card .x-p { display: block; margin-top: 4px; font: 400 14px/20px var(--x-font); color: var(--x-mute); }
.x-arrow { flex: none; font: 400 24px/32px var(--x-font); transition: transform var(--x-fast) var(--x-ease); }
.x-card:hover .x-arrow { transform: translateX(4px); }
.x-card--resume { border: 1px solid var(--x-ink); border-left: 4px solid var(--x-accent); padding: 16px; min-height: 72px; margin-top: 24px; }
.x-banner { display: flex; align-items: center; gap: 16px; margin-top: 24px; padding: 16px; border: 1px solid var(--x-ink); border-left: 4px solid var(--x-accent); border-radius: 2px; }
.x-banner p { flex: 1; margin: 0; font: 500 14px/20px var(--x-font); }

/* tabs: bottom bar on phones, top bar on desktop */
.x-tabs {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 40; display: grid; grid-template-columns: repeat(3, 1fr);
  background: var(--x-bg); border-top: 1px solid var(--x-ink); padding: 0 env(safe-area-inset-right) var(--x-safe-b) env(safe-area-inset-left);
}
.x-tabs__brand { display: none; }
.x-tabs button {
  position: relative; background: none; border: 0; color: var(--x-mute); font: 600 12px/16px var(--x-font);
  padding: 8px 0; min-height: var(--x-tabh); display: grid; gap: 4px; justify-items: center; align-content: center; cursor: pointer;
  transition: transform var(--x-fast) var(--x-ease), color var(--x-fast) var(--x-ease);
}
.x-tabs button.is-on { color: var(--x-ink); }
.x-tabs button.is-on::before { content: ""; position: absolute; top: -1px; left: 50%; width: 32px; margin-left: -16px; height: 2px; background: var(--x-accent); }
.x-tabs .x-ti { width: 24px; height: 24px; display: block; }
body.is-playing .x-tabs { display: none; }
body.is-playing .x-app { padding-bottom: calc(16px + var(--x-safe-b)); }

/* ---------- generic controls ---------- */
.x-btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border: 1px solid var(--x-ink); background: var(--x-bg); color: var(--x-ink); border-radius: 2px; min-height: 44px;
  font: 600 14px/20px var(--x-font); padding: 0 16px; cursor: pointer; text-decoration: none;
  transition: transform var(--x-fast) var(--x-ease), background var(--x-fast) var(--x-ease), color var(--x-fast) var(--x-ease), opacity var(--x-fast) var(--x-ease);
}
.x-btn:hover { background: var(--x-off); }
.x-btn--on, .x-btn--on:hover { background: var(--x-ink); color: var(--x-bg); }
.x-btn--s { min-height: 36px; padding: 0 12px; font-size: 13px; }
.x-btn--danger { border-color: var(--x-accent); color: var(--x-accent); }
.x-btn:disabled { opacity: .4; cursor: default; }
.x-btn:active, .x-card:active, .x-icon:active, .x-tabs button:active, .x-cta:not(:disabled):active, .x-room:active, .x-textbtn:active,
.x-act:not(:disabled):active, .x-quick button:active, .x-chip:active, .x-seg button:active { transform: scale(.97); }
.x-icon {
  flex: none; width: 44px; height: 44px; border-radius: 2px; border: 1px solid var(--x-ink); background: none; color: inherit;
  cursor: pointer; display: grid; place-items: center; transition: transform var(--x-fast) var(--x-ease), background var(--x-fast) var(--x-ease);
}
.x-icon svg, .x-act svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round; }
.x-icon--ghost { border-color: transparent; }
.x-icon:hover { background: var(--x-off); }
.x-cta {
  display: block; width: 100%; min-height: 56px; border: 0; border-radius: 2px; background: var(--x-off); color: var(--x-mute);
  font: 700 16px/24px var(--x-font); cursor: not-allowed; transition: background var(--x-mid) var(--x-ease), color var(--x-mid) var(--x-ease), transform var(--x-fast) var(--x-ease);
}
.x-cta:not(:disabled) { background: var(--x-accent); color: #000000; cursor: pointer; }
.x-textbtn { display: block; width: 100%; min-height: 44px; margin-top: 8px; background: none; border: 0; color: var(--x-ink); font: 600 14px/20px var(--x-font); text-decoration: underline; text-underline-offset: 4px; cursor: pointer; transition: transform var(--x-fast) var(--x-ease); }
.x-in {
  display: block; width: 100%; min-height: 48px; border: 1px solid var(--x-ink); border-radius: 2px; background: none; color: inherit;
  padding: 0 16px; font: 500 16px/24px var(--x-font); transition: border-color var(--x-fast) var(--x-ease);
}
.x-in::placeholder { color: var(--x-mute); font-weight: 400; }
.x-in[aria-invalid="true"] { border-color: var(--x-accent); }
.x-label { display: block; margin: 16px 0 8px; font: 600 12px/16px var(--x-font); letter-spacing: .04em; color: var(--x-mute); }
.x-err { min-height: 20px; margin: 8px 0 0; font: 600 13px/20px var(--x-font); color: var(--x-accent); }
.x-err:empty { min-height: 0; margin: 0; }
.x-hint { margin: 8px 0 0; font: 400 12px/16px var(--x-font); color: var(--x-mute); }
.x-tag { display: inline-block; font: 600 12px/16px var(--x-font); border: 1px solid var(--x-ink); border-radius: 2px; padding: 4px 8px; color: var(--x-ink); white-space: nowrap; }
.x-tag--on { background: var(--x-accent); border-color: var(--x-accent); color: #000000; }
.x-tag--mute { border-color: var(--x-hair); color: var(--x-mute); }

/* avatars */
.x-av {
  width: 40px; height: 40px; border-radius: 2px; display: grid; place-items: center; flex: none; overflow: hidden;
  background: var(--x-ink); color: var(--x-bg); font: 700 16px/1 var(--x-font); text-transform: uppercase;
}
.x-av--accent { background: var(--x-accent); color: #000; }
.x-av--mute { background: var(--x-mute); color: var(--x-bg); }
.x-av--line { background: none; color: var(--x-ink); border: 1px solid var(--x-ink); }
.x-av--ai { background: none; color: var(--x-ink); border: 1px dashed var(--x-ink); }
.x-av--sm { width: 32px; height: 32px; font-size: 14px; }
.x-av--xs { width: 36px; height: 36px; font-size: 14px; }
.x-av--lg { width: 64px; height: 64px; font-size: 24px; }
.x-chip .x-av { width: 36px; height: 36px; font-size: 14px; }

/* ---------- play ---------- */
.x-bar { display: flex; align-items: center; gap: 16px; padding: 0 0 16px; margin-bottom: 16px; border-bottom: 1px solid var(--x-ink); }
.x-bar__t { flex: 1; min-width: 0; }
.x-bar h2 { font: 700 24px/32px var(--x-font); letter-spacing: -0.03em; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.x-bar__sub { display: block; font: 500 12px/16px var(--x-font); color: var(--x-mute); font-variant-numeric: tabular-nums; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.x-playgrid { display: grid; grid-template-columns: minmax(0, 1fr); grid-template-areas: "players" "board" "status" "offer" "acts"; }
.x-players { grid-area: players; }
.x-boardcol { grid-area: board; position: relative; }
.x-status { grid-area: status; }
.x-offerslot { grid-area: offer; }
.x-acts { grid-area: acts; }
.x-movelist { grid-area: moves; display: none; }
.x-chatpanel { grid-area: chat; }

.x-players { position: relative; display: grid; grid-template-columns: 1fr 1fr; border: 1px solid var(--x-ink); margin-bottom: 16px; }
.x-pl { display: flex; align-items: center; gap: 8px; padding: 8px 12px; min-height: 56px; min-width: 0; transition: opacity var(--x-mid) var(--x-ease); }
.x-pl + .x-pl { border-left: 1px solid var(--x-ink); }
.x-pl:not(.is-turn) { opacity: .62; }
.x-players.is-over .x-pl { opacity: 1; }
.x-pl .x-grow { min-width: 0; flex: 1; }
.x-pl b { display: block; font: 700 16px/24px var(--x-font); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.x-pl__sub { display: flex; align-items: center; gap: 6px; font: 400 12px/16px var(--x-font); color: var(--x-mute); white-space: nowrap; overflow: hidden; }
.x-ind { position: absolute; left: 0; bottom: -1px; width: 50%; height: 4px; background: var(--x-accent); transition: transform var(--x-slow) var(--x-ease), opacity var(--x-mid) var(--x-ease); }
.x-players.is-b .x-ind { transform: translateX(100%); }
.x-players.is-over .x-ind { opacity: 0; }
.x-stone { width: 12px; height: 12px; border-radius: 50%; flex: none; border: 1px solid var(--x-ink); }
.x-stone--b { background: #000000; }
.x-stone--w { background: #ffffff; }
.x-stone--r { background: var(--x-accent); border-color: var(--x-accent); }
.x-pl .x-on { display: inline-block; width: 8px; height: 8px; border-radius: 50%; margin-left: 6px; vertical-align: middle; background: var(--x-accent); }
.x-pl .x-on.is-off { background: none; border: 1px solid var(--x-mute); }

/* board: as large as the viewport allows, never pushed by chat */
.x-boardwrap {
  --ar: 1; position: relative; width: min(100%, calc((100dvh - 312px - var(--x-safe-t) - var(--x-safe-b)) * var(--ar))); min-width: min(100%, 280px);
  margin: 0 auto; aspect-ratio: var(--ar); border: 1px solid var(--x-ink); overflow: hidden; background: var(--x-board);
}
.x-boardwrap svg { display: block; width: 100%; height: 100%; touch-action: manipulation; }
.x-drop { animation: x-drop var(--x-mid) var(--x-ease); transform-origin: center; }
@keyframes x-drop { from { opacity: 0; transform: scale(1.35); } to { opacity: 1; transform: scale(1); } }
.x-slide { animation: x-slide var(--x-slow) var(--x-ease); }
@keyframes x-slide { from { transform: translate(var(--dx), var(--dy)); } to { transform: none; } }
.x-flip { transform-origin: center; animation: x-flip var(--x-mid) var(--x-ease) var(--d, 0ms) backwards; }
.x-flip circle { animation: x-fb var(--x-mid) linear var(--d, 0ms) backwards; }
.x-flip.x-fw circle { animation-name: x-fw; }
@keyframes x-flip { 0% { transform: scaleX(1); } 50% { transform: scaleX(0); } 100% { transform: scaleX(1); } }
@keyframes x-fw { 0%, 50% { fill: #ffffff; } 50.01%, 100% { fill: #000000; } }
@keyframes x-fb { 0%, 50% { fill: #000000; } 50.01%, 100% { fill: #ffffff; } }

.x-status { margin: 0; padding: 8px 0; font: 500 14px/24px var(--x-font); color: var(--x-mute); min-height: 40px; text-align: center; }
.x-acts { display: grid; grid-auto-flow: column; grid-auto-columns: minmax(0, 1fr); border: 1px solid var(--x-ink); }
.x-act {
  position: relative; display: grid; justify-items: center; align-content: center; gap: 2px; min-height: 56px; padding: 4px; border: 0; border-radius: 0;
  background: none; color: inherit; font: 600 12px/16px var(--x-font); cursor: pointer; transition: background var(--x-fast) var(--x-ease), transform var(--x-fast) var(--x-ease);
}
.x-act + .x-act { border-left: 1px solid var(--x-hair); }
.x-act:hover:not(:disabled) { background: var(--x-off); }
.x-act:disabled { opacity: .35; cursor: default; }
.x-act[aria-expanded="true"] { color: var(--x-accent); }
.x-badge { position: absolute; top: 8px; right: calc(50% - 18px); width: 8px; height: 8px; border-radius: 50%; background: var(--x-accent); }
.x-offer { display: flex; align-items: center; gap: 8px; margin: 0 0 16px; padding: 8px 8px 8px 16px; border: 1px solid var(--x-ink); border-left: 4px solid var(--x-accent); border-radius: 2px; font: 600 14px/20px var(--x-font); animation: x-in var(--x-mid) var(--x-ease); }
.x-offer span { flex: 1; min-width: 0; }
.x-offer .x-btn { min-height: 40px; padding: 0 12px; }

/* chat bubbles float over the board top; never reflow the layout */
.x-bubbles { position: absolute; left: 8px; right: 8px; top: 8px; display: grid; gap: 8px; pointer-events: none; z-index: 2; }
.x-bub { justify-self: start; max-width: 85%; border: 1px solid var(--x-ink); border-radius: 2px; padding: 8px 12px; font: 500 14px/20px var(--x-font); background: var(--x-bg); animation: x-in var(--x-mid) var(--x-ease); box-shadow: 0 2px 0 var(--x-ink); }
.x-bub.is-me { justify-self: end; background: var(--x-ink); color: var(--x-bg); }

/* chat: bottom drawer on phones, inline panel on desktop */
.x-chatpanel {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 55; max-width: 560px; margin: 0 auto; display: flex; flex-direction: column; max-height: 70dvh;
  background: var(--x-bg); border: 1px solid var(--x-ink); border-bottom: 0; border-radius: 4px 4px 0 0; padding: 8px 16px calc(16px + var(--x-safe-b));
  transform: translateY(100%); visibility: hidden; transition: transform var(--x-slow) var(--x-ease), visibility 0s var(--x-slow);
}
.x-chatpanel.is-on { transform: none; visibility: visible; transition: transform var(--x-slow) var(--x-ease); }
.x-chatpanel__head { display: flex; align-items: center; justify-content: space-between; }
.x-chatpanel__head .x-sec { margin: 0; }
.x-chatlog { flex: 1; min-height: 96px; max-height: 40dvh; overflow-y: auto; display: flex; flex-direction: column; gap: 8px; padding: 8px 0; border-top: 1px solid var(--x-hair); border-bottom: 1px solid var(--x-hair); }
.x-msg { align-self: flex-start; max-width: 85%; font: 400 14px/20px var(--x-font); }
.x-msg b { display: block; font: 600 12px/16px var(--x-font); color: var(--x-mute); }
.x-msg span { display: inline-block; border: 1px solid var(--x-ink); border-radius: 2px; padding: 6px 12px; overflow-wrap: anywhere; }
.x-msg.is-me { align-self: flex-end; text-align: right; }
.x-msg.is-me span { background: var(--x-ink); color: var(--x-bg); }
.x-chatlog .x-empty { margin: auto; }
.x-emotes { display: flex; gap: 8px; overflow-x: auto; padding: 8px 0; scrollbar-width: none; }
.x-emotes button { white-space: nowrap; flex: none; }
.x-chatrow { display: flex; gap: 8px; }
.x-chatrow input { flex: 1; min-width: 0; min-height: 44px; border: 1px solid var(--x-ink); border-radius: 2px; background: none; color: inherit; padding: 0 16px; font: 400 16px/20px var(--x-font); }
.x-chatrow input::placeholder { color: var(--x-mute); }

.x-movelist__ol { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: 40px 1fr 1fr; font: 400 13px/24px var(--x-mono); max-height: 240px; overflow-y: auto; border-top: 1px solid var(--x-hair); }
.x-movelist__ol li { display: contents; }
.x-movelist__ol .n { color: var(--x-mute); }
.x-movelist__ol .is-last { color: var(--x-accent); font-weight: 700; }
.x-movelist .x-empty { grid-column: 1 / -1; padding: 8px 0; }

/* ---------- lists, rows, stats ---------- */
.x-top { padding: 8px 0 24px; margin-bottom: 24px; border-bottom: 1px solid var(--x-ink); }
.x-top h1 { font: 700 48px/56px var(--x-font); letter-spacing: -0.05em; margin-top: 8px; }
.x-top p { margin: 16px 0 0; color: var(--x-mute); font: 500 14px/24px var(--x-font); }
.x-list { border-top: 1px solid var(--x-ink); border-bottom: 1px solid var(--x-ink); }
.x-row { display: flex; align-items: center; gap: 16px; padding: 12px 0; border-bottom: 1px solid var(--x-hair); min-height: 64px; }
.x-row:last-child { border-bottom: 0; }
.x-row b { font: 700 16px/24px var(--x-font); }
.x-row .x-grow { flex: 1; min-width: 0; }
.x-row .x-grow > * { display: block; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.x-row .x-btn { flex: none; }
.x-row.is-click { cursor: pointer; }
.x-row.is-click:hover { background: var(--x-off); }
.x-meta { font: 400 12px/16px var(--x-font); color: var(--x-mute); }
.x-dotg, .x-doto, .x-dotp { width: 8px; height: 8px; border-radius: 50%; display: inline-block; margin-right: 8px; vertical-align: 1px; }
.x-dotg { background: var(--x-ink); } .x-doto { background: var(--x-accent); } .x-dotp { border: 1px solid var(--x-mute); }
.x-res { flex: none; width: 32px; height: 32px; display: grid; place-items: center; border: 1px solid var(--x-ink); border-radius: 2px; font: 700 14px/1 var(--x-font); }
.x-res--win { background: var(--x-accent); border-color: var(--x-accent); color: #000; }
.x-res--loss { background: var(--x-ink); color: var(--x-bg); }
.x-empty { margin: 0; padding: 24px 0; font: 400 14px/24px var(--x-font); color: var(--x-mute); text-align: center; }
.x-skel { height: 64px; border-bottom: 1px solid var(--x-hair); background: linear-gradient(90deg, transparent 0, var(--x-off) 40%, transparent 80%) 0 0 / 200% 100%; animation: x-skel 1.2s linear infinite; }
@keyframes x-skel { to { background-position: -200% 0; } }

.x-acct { display: flex; align-items: center; gap: 16px; padding: 16px; border: 1px solid var(--x-ink); }
.x-acct .x-grow { flex: 1; min-width: 0; }
.x-acct b { display: block; font: 700 24px/32px var(--x-font); letter-spacing: -0.02em; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.x-stats { display: grid; grid-template-columns: repeat(4, 1fr); border: 1px solid var(--x-ink); }
.x-statc { padding: 16px 12px; min-width: 0; }
.x-statc + .x-statc { border-left: 1px solid var(--x-ink); }
.x-statc b { display: block; font: 700 32px/40px var(--x-font); letter-spacing: -0.04em; font-variant-numeric: tabular-nums; }
.x-statc span { font: 400 12px/16px var(--x-font); color: var(--x-mute); }
.x-statc.is-win b { color: var(--x-accent); }
.x-bygame { width: 100%; border-collapse: collapse; margin-top: 8px; font: 400 14px/20px var(--x-font); font-variant-numeric: tabular-nums; }
.x-bygame th, .x-bygame td { padding: 8px 0; border-bottom: 1px solid var(--x-hair); text-align: right; }
.x-bygame th { font: 600 12px/16px var(--x-font); color: var(--x-mute); }
.x-bygame th:first-child, .x-bygame td:first-child { text-align: left; }
.x-sw { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 8px 0; min-height: 56px; border-bottom: 1px solid var(--x-hair); font: 500 16px/24px var(--x-font); }
.x-sw:last-child { border-bottom: 0; }
.x-seg { display: inline-flex; border: 1px solid var(--x-ink); border-radius: 2px; }
.x-seg button { min-height: 40px; min-width: 56px; padding: 0 12px; border: 0; background: none; color: inherit; font: 600 13px/20px var(--x-font); cursor: pointer; transition: background var(--x-fast) var(--x-ease), color var(--x-fast) var(--x-ease); }
.x-seg button + button { border-left: 1px solid var(--x-ink); }
.x-seg button[aria-pressed="true"] { background: var(--x-ink); color: var(--x-bg); }
.x-switch { position: relative; width: 52px; height: 32px; border: 1px solid var(--x-ink); border-radius: 16px; background: none; cursor: pointer; padding: 0; flex: none; transition: background var(--x-fast) var(--x-ease); }
.x-switch::after { content: ""; position: absolute; top: 3px; left: 3px; width: 24px; height: 24px; border-radius: 50%; background: var(--x-ink); transition: transform var(--x-mid) var(--x-ease), background var(--x-mid) var(--x-ease); }
.x-switch[aria-checked="true"] { background: var(--x-accent); border-color: var(--x-accent); }
.x-switch[aria-checked="true"]::after { transform: translateX(20px); background: #000; }
.x-menu .x-row { min-height: 56px; }
.x-menu .x-row .x-arrow { font-size: 20px; color: var(--x-mute); }
.x-keyrow { padding: 16px 0; border-bottom: 1px solid var(--x-hair); }
.x-keyrow:last-child { border-bottom: 0; }
.x-keyrow__h { display: flex; align-items: baseline; gap: 8px; min-width: 0; }
.x-keyrow__h b { font: 700 16px/24px var(--x-font); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.x-keyrow code { font: 400 12px/16px var(--x-mono); color: var(--x-mute); }
.x-keyrow__acts { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 8px; }
.x-off-note { padding: 16px; border: 1px dashed var(--x-hair); color: var(--x-mute); font: 400 13px/20px var(--x-font); }

/* auth form */
.x-auth { padding: 24px 16px; border: 1px solid var(--x-ink); border-top: 4px solid var(--x-accent); }
.x-auth h3 { font: 700 32px/40px var(--x-font); letter-spacing: -0.03em; }
.x-auth > p { margin: 8px 0 0; font: 400 14px/20px var(--x-font); color: var(--x-mute); }
.x-auth .x-cta { margin-top: 24px; }
.x-pw { position: relative; }
.x-pw .x-in { padding-right: 56px; }
.x-pw button { position: absolute; right: 2px; top: 2px; bottom: 2px; width: 48px; border: 0; background: none; color: var(--x-mute); font: 600 12px/16px var(--x-font); cursor: pointer; }

/* ---------- sheet, modal, toast ---------- */
.x-sheet-bg { position: fixed; inset: 0; z-index: 50; background: #00000099; opacity: 0; transition: opacity var(--x-mid) var(--x-ease); }
.x-sheet-bg.is-on { opacity: 1; }
.x-sheet {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 51; max-width: 560px; margin: 0 auto;
  background: var(--x-bg); border: 1px solid var(--x-ink); border-bottom: 0; border-radius: 4px 4px 0 0;
  padding: 24px 16px calc(24px + var(--x-safe-b)); max-height: 90dvh; overflow: auto; overscroll-behavior: contain;
  transform: translateY(100%); transition: transform var(--x-slow) var(--x-ease);
}
.x-sheet.is-on { transform: none; }
.x-sheet h3 { margin: 0 0 16px; font: 700 32px/40px var(--x-font); letter-spacing: -0.03em; }
.x-sheet h3.x-big { margin: 0 0 8px; font-size: 48px; line-height: 56px; letter-spacing: -0.05em; }
.x-sheet p { margin: 0 0 16px; font: 400 14px/24px var(--x-font); color: var(--x-mute); }
.x-sheet .x-eyebrow { margin-bottom: 8px; }
.x-sheet .x-btn:not(.x-btn--s):not(.x-inl) { width: 100%; margin-top: 8px; }
.x-sheet .x-cta { margin-top: 16px; }
.x-sheet .x-auth { border: 0; padding: 0; }
.x-sheet .x-in + .x-in { margin-top: 8px; }
.x-sizes { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; margin-bottom: 8px; }
.x-sheet .x-sizes .x-btn { margin-top: 0; }
.x-picker { border-top: 1px solid var(--x-ink); margin-bottom: 8px; }
.x-picker .x-card { min-height: 64px; padding: 8px 0; }
.x-picker .x-num { font-size: 24px; line-height: 32px; min-width: 40px; }
.x-picker .x-card .x-h { font-size: 18px; line-height: 24px; }
.x-swatches { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; }
.x-swatches button { min-height: 72px; border: 1px solid var(--x-hair); border-radius: 2px; background: none; cursor: pointer; display: grid; place-items: center; }
.x-swatches button[aria-pressed="true"] { border: 2px solid var(--x-accent); }
.x-replay__board { width: min(100%, 60dvh); margin: 0 auto 16px; border: 1px solid var(--x-ink); aspect-ratio: var(--ar, 1); }
.x-replay__board svg { display: block; width: 100%; height: 100%; }
.x-replay__nav { display: grid; grid-template-columns: 44px 44px 1fr 44px 44px; gap: 8px; align-items: center; }
.x-replay__nav span { text-align: center; font: 600 14px/20px var(--x-font); font-variant-numeric: tabular-nums; }
.x-sheet .x-replay__nav .x-btn { width: auto; margin: 0; padding: 0; }

.x-room { display: block; width: 100%; text-align: left; color: inherit; background: none; border: 1px solid var(--x-ink); border-radius: 0; padding: 16px; margin: 8px 0 16px; cursor: pointer; transition: transform var(--x-fast) var(--x-ease); }
.x-room__label { display: flex; justify-content: space-between; font: 600 12px/16px var(--x-font); letter-spacing: .08em; text-transform: uppercase; color: var(--x-mute); }
.x-room__code { display: block; margin-top: 8px; font: 700 48px/56px var(--x-font); letter-spacing: -0.02em; font-variant-numeric: tabular-nums; }
.x-linkrow { display: flex; gap: 8px; }
.x-linkrow input { flex: 1; min-width: 0; min-height: 44px; border: 1px solid var(--x-hair); border-radius: 2px; background: none; color: var(--x-mute); padding: 0 16px; font: 400 14px/20px var(--x-font); }
.x-sheet .x-linkrow .x-btn { width: auto; margin-top: 0; }
.x-wait { display: flex; align-items: center; gap: 8px; margin: 24px 0 16px; font: 600 14px/24px var(--x-font); }
.x-spin { width: 16px; height: 16px; border: 2px solid var(--x-hair); border-top-color: var(--x-accent); border-radius: 50%; animation: x-spin 800ms linear infinite; }
.x-wait.is-done .x-spin { display: none; }
.x-wait.is-done::before { content: ""; width: 8px; height: 8px; background: var(--x-accent); }
@keyframes x-spin { to { transform: rotate(360deg); } }
.x-seats { display: flex; gap: 8px; margin-bottom: 24px; }
.x-seat { width: 48px; height: 48px; display: grid; place-items: center; border: 1px dashed var(--x-mute); border-radius: 2px; color: var(--x-mute); font: 700 16px/24px var(--x-font); }
.x-seat.is-in { border: 1px solid var(--x-ink); background: var(--x-ink); color: var(--x-bg); animation: x-drop var(--x-mid) var(--x-ease); }
.x-code { display: block; width: 100%; overflow-wrap: anywhere; border: 1px solid var(--x-ink); border-radius: 2px; padding: 16px; margin: 8px 0; font: 400 13px/20px var(--x-mono); background: var(--x-off); color: var(--x-ink); white-space: pre-wrap; user-select: all; }
.x-field { display: flex; gap: 8px; margin-top: 8px; }
.x-field input {
  flex: 1; min-width: 0; min-height: 56px; border: 1px solid var(--x-ink); border-radius: 2px; background: none; color: inherit;
  padding: 0 16px; font: 700 24px/32px var(--x-font); letter-spacing: .04em; text-transform: uppercase; font-variant-numeric: tabular-nums;
}
.x-field input::placeholder { color: var(--x-mute); font-weight: 400; }
.x-field .x-btn { min-height: 56px; min-width: 88px; }

.x-modal { position: fixed; inset: 0; z-index: 60; display: flex; align-items: flex-end; justify-content: center; background: #00000099; opacity: 0; transition: opacity var(--x-mid) var(--x-ease); }
.x-modal.is-on { opacity: 1; }
.x-modal__card {
  width: 100%; max-width: 560px; background: var(--x-bg); border: 1px solid var(--x-ink); border-top: 4px solid var(--x-accent); border-bottom: 0;
  border-radius: 4px 4px 0 0; padding: 32px 16px calc(24px + var(--x-safe-b)); transform: translateY(100%); transition: transform var(--x-slow) var(--x-ease);
}
.x-modal.is-on .x-modal__card { transform: none; }
.x-modal h3 { margin: 8px 0 16px; font: 700 64px/64px var(--x-font); letter-spacing: -0.05em; }
.x-modal p.x-res-p { margin: 0 0 24px; font: 400 14px/24px var(--x-font); color: var(--x-mute); }
.x-modal .x-btn { width: 100%; margin-top: 8px; }

.x-toast {
  position: fixed; left: 50%; top: calc(16px + var(--x-safe-t)); z-index: 70; max-width: calc(100% - 32px);
  transform: translate(-50%, -16px); opacity: 0; pointer-events: none; background: var(--x-ink); color: var(--x-bg);
  border-left: 4px solid var(--x-accent); border-radius: 2px; padding: 8px 16px; font: 600 14px/24px var(--x-font);
  transition: opacity var(--x-mid) var(--x-ease), transform var(--x-mid) var(--x-ease);
}
.x-toast.is-on { opacity: 1; transform: translate(-50%, 0); }
.x-net { position: fixed; right: 16px; top: calc(16px + var(--x-safe-t)); z-index: 45; font: 600 12px/16px var(--x-font); padding: 4px 8px; border-radius: 2px; background: var(--x-accent); color: #000; }

/* ---------- markdown (Agent 接入) ---------- */
.x-md { font: 400 15px/24px var(--x-font); }
.x-md h1 { display: none; }
.x-md h2 { margin: 40px 0 8px; padding-top: 16px; border-top: 1px solid var(--x-ink); font: 700 24px/32px var(--x-font); letter-spacing: -0.02em; }
.x-md h2:first-of-type { margin-top: 24px; }
.x-md h3 { margin: 24px 0 8px; font: 700 16px/24px var(--x-font); }
.x-md p, .x-md li { color: var(--x-ink); }
.x-md p { margin: 8px 0; }
.x-md ul, .x-md ol { margin: 8px 0; padding-left: 24px; }
.x-md li { margin: 4px 0; }
.x-md blockquote { margin: 16px 0; padding: 12px 16px; border-left: 4px solid var(--x-accent); background: var(--x-off); }
.x-md blockquote p { margin: 0; }
.x-md code { font: 400 13px/20px var(--x-mono); background: var(--x-off); padding: 1px 4px; border-radius: 2px; }
.x-md a { color: inherit; text-underline-offset: 4px; overflow-wrap: anywhere; }
.x-pre { position: relative; margin: 8px 0 16px; border: 1px solid var(--x-ink); background: var(--x-off); }
.x-pre pre { margin: 0; padding: 16px; padding-right: 72px; overflow-x: auto; font: 400 13px/20px var(--x-mono); white-space: pre; }
.x-pre code { background: none; padding: 0; }
.x-pre .x-btn { position: absolute; top: 8px; right: 8px; min-height: 32px; padding: 0 10px; font-size: 12px; }
.x-pre--wrap pre { white-space: pre-wrap; }
.x-tablewrap { overflow-x: auto; margin: 8px 0 16px; }
.x-md table { border-collapse: collapse; width: 100%; font-size: 13px; line-height: 20px; }
.x-md th, .x-md td { text-align: left; padding: 8px 12px 8px 0; border-bottom: 1px solid var(--x-hair); vertical-align: top; }
.x-md th { font-weight: 600; color: var(--x-mute); border-bottom-color: var(--x-ink); }

/* ---------- tablet & desktop ---------- */
@media (min-width: 720px) {
  .x-quick { grid-template-columns: repeat(4, 1fr); }
  .x-hero h1 { font-size: 96px; line-height: 96px; }
  .x-sheet { border-bottom: 1px solid var(--x-ink); border-radius: 4px; bottom: 50%; }
  .x-sheet { transform: translateY(calc(50% + 24px)); opacity: 0; transition: transform var(--x-slow) var(--x-ease), opacity var(--x-mid) var(--x-ease); max-height: 86dvh; }
  .x-sheet.is-on { transform: translateY(50%); opacity: 1; }
  .x-modal { align-items: center; }
  .x-modal__card { transform: translateY(24px); border-bottom: 1px solid var(--x-ink); }
}
@media (min-width: 960px) {
  :root { --x-tabh: 64px; }
  .x-app { max-width: 1200px; padding: calc(var(--x-tabh) + 32px) 32px 48px; }
  /* top bar aligned with the content column (880px; 1136px while playing) */
  .x-tabs { top: 0; bottom: auto; border-top: 0; border-bottom: 1px solid var(--x-ink); grid-template-columns: 1fr auto auto auto; align-items: stretch;
    padding: 0 max(32px, calc((100vw - 880px) / 2)); height: var(--x-tabh); }
  body.is-playing .x-tabs { padding: 0 max(32px, calc((100vw - 1136px) / 2)); }
  .x-tabs__brand { display: block; align-self: center; font: 700 24px/32px var(--x-font); letter-spacing: -0.04em; }
  .x-tabs button { display: flex; align-items: center; justify-content: center; gap: 8px; height: 100%; min-height: 0; padding: 0 16px; font-size: 14px; line-height: 20px; }
  .x-tabs .x-ti { width: 20px; height: 20px; }
  .x-tabs button.is-on::before { top: auto; bottom: 0; left: 16px; right: 16px; width: auto; margin: 0; height: 3px; }
  body.is-playing .x-tabs { display: grid; }
  body.is-playing .x-app { padding-bottom: 48px; }
  #s-home, #s-friends, #s-me, #s-agent { max-width: 880px; margin: 0 auto; }
  .x-playgrid {
    grid-template-columns: minmax(0, 1fr) 360px; column-gap: 32px;
    grid-template-areas: "board players" "board status" "board offer" "board acts" "board moves" "board chat";
    grid-template-rows: auto auto auto auto auto minmax(0, 1fr);
  }
  .x-boardwrap { width: min(100%, calc((100dvh - 220px) * var(--ar))); }
  .x-status { text-align: left; padding: 16px 0; }
  .x-movelist { display: block; }
  .x-movelist .x-sec { margin-top: 24px; }
  .x-bubbles { display: none; }
  #btn-chat { display: none !important; }
  .x-chatpanel { position: static; transform: none; visibility: visible; max-width: none; margin: 24px 0 0; padding: 0; border: 0; border-radius: 0; max-height: none; }
  .x-chatpanel #chat-close { display: none; }
  .x-chatlog { max-height: 220px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 1ms !important; animation-delay: 0ms !important; animation-iteration-count: 1 !important; transition-duration: 1ms !important; transition-delay: 0ms !important; }
}