/* Interview Room. Colours are tokens on :root, redefined for dark mode. */
:root {
  --bg: #f4f5f8; --panel: #ffffff; --panel-2: #f8f9fb; --border: #e1e4ea; --border-strong: #cfd4dc;
  --fg: #1b2230; --muted: #5d6879; --faint: #8a93a3;
  --accent: #4263eb; --accent-fg: #ffffff; --accent-soft: #e8edff;
  --ok: #2b8a3e; --ok-soft: #e6f4ea; --bad: #d6336c; --bad-soft: #fdebf1; --warn: #e67700; --warn-soft: #fff4e0;
  --editor-bg: #fbfcfd; --gutter: #a0a8b6; --selection: rgba(66, 99, 235, .22);
  --t-keyword: #7c3aed; --t-string: #2b8a3e; --t-number: #c2410c; --t-comment: #8a94a3; --t-function: #1c5fd4;
  --t-literal: #c2410c; --t-builtin: #0e7490; --t-type: #a15c07; --t-decorator: #be185d;
  --c0: #3b6cf6; --c1: #f76707; --c2: #12b886; --c3: #9c36b5; --c4: #e03131; --c5: #d9a400; --c6: #1098ad; --c7: #d6336c;
  --shadow: 0 1px 2px rgba(16, 24, 40, .06), 0 4px 16px rgba(16, 24, 40, .06);
  --radius: 10px;
  --mono: ui-monospace, "Cascadia Code", "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --code-size: 14px; --code-lh: 21px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0d1117; --panel: #151a22; --panel-2: #1a2029; --border: #262e3a; --border-strong: #354050;
    --fg: #e6e9ef; --muted: #9aa4b5; --faint: #6d7788;
    --accent: #7b96ff; --accent-fg: #0d1117; --accent-soft: #1e2744;
    --ok: #69db7c; --ok-soft: #13291a; --bad: #ff8fab; --bad-soft: #33161f; --warn: #ffb54a; --warn-soft: #33260f;
    --editor-bg: #10151c; --gutter: #4f5a6b; --selection: rgba(123, 150, 255, .28);
    --t-keyword: #c7a6ff; --t-string: #94d79c; --t-number: #ffb07a; --t-comment: #6f7a8c; --t-function: #85adff;
    --t-literal: #ffb07a; --t-builtin: #6ad3e6; --t-type: #f5c876; --t-decorator: #f59ac4;
    --c0: #6c95ff; --c1: #ff922b; --c2: #38d9a9; --c3: #cc5de8; --c4: #ff6b6b; --c5: #ffd43b; --c6: #3bc9db; --c7: #f783ac;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 6px 20px rgba(0, 0, 0, .25);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0d1117; --panel: #151a22; --panel-2: #1a2029; --border: #262e3a; --border-strong: #354050;
  --fg: #e6e9ef; --muted: #9aa4b5; --faint: #6d7788;
  --accent: #7b96ff; --accent-fg: #0d1117; --accent-soft: #1e2744;
  --ok: #69db7c; --ok-soft: #13291a; --bad: #ff8fab; --bad-soft: #33161f; --warn: #ffb54a; --warn-soft: #33260f;
  --editor-bg: #10151c; --gutter: #4f5a6b; --selection: rgba(123, 150, 255, .28);
  --t-keyword: #c7a6ff; --t-string: #94d79c; --t-number: #ffb07a; --t-comment: #6f7a8c; --t-function: #85adff;
  --t-literal: #ffb07a; --t-builtin: #6ad3e6; --t-type: #f5c876; --t-decorator: #f59ac4;
  --c0: #6c95ff; --c1: #ff922b; --c2: #38d9a9; --c3: #cc5de8; --c4: #ff6b6b; --c5: #ffd43b; --c6: #3bc9db; --c7: #f783ac;
  --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 6px 20px rgba(0, 0, 0, .25);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body { margin: 0; background: var(--bg); color: var(--fg); font: 15px/1.5 var(--sans); display: flex; flex-direction: column; }
[hidden] { display: none !important; }
h1, h2, h3 { line-height: 1.25; margin: 0; }
code, pre, kbd { font-family: var(--mono); font-variant-ligatures: none; }
.muted { color: var(--muted); }
.spacer { flex: 1; }
a { color: var(--accent); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- buttons and inputs ---------- */
.btn { font: inherit; font-weight: 600; font-size: 14px; border: 1px solid var(--border-strong); background: var(--panel); color: var(--fg);
  padding: 8px 14px; border-radius: 8px; cursor: pointer; display: inline-flex; align-items: center; gap: 6px; white-space: nowrap; }
.btn:hover { border-color: var(--accent); }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.btn.small { padding: 5px 10px; font-size: 13px; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-fg); }
.btn.primary:hover { filter: brightness(1.08); }
.btn.ghost { background: transparent; border-color: transparent; color: var(--muted); }
.btn.ghost:hover { color: var(--fg); background: var(--panel-2); }
.btn.danger { color: var(--bad); border-color: var(--bad); background: transparent; }
.btn.danger:hover { background: var(--bad-soft); }
.btn.icon { padding: 6px; width: 34px; height: 34px; justify-content: center; }
.btn svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.btn .i-moon { fill: currentColor; stroke: none; }
:root .i-sun { display: none; }
:root[data-theme="dark"] .i-sun { display: block; }
:root[data-theme="dark"] .i-moon { display: none; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .i-sun { display: block; }
  :root:not([data-theme="light"]) .i-moon { display: none; }
}
input, select, textarea { font: inherit; color: var(--fg); background: var(--panel); border: 1px solid var(--border-strong); border-radius: 8px; padding: 8px 10px; }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
select { padding: 4px 8px; font-size: 13px; }

/* ---------- top bar ---------- */
.topbar { display: flex; align-items: center; gap: 14px; padding: 8px 16px; background: var(--panel); border-bottom: 1px solid var(--border); min-height: 54px; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: 8px; color: var(--fg); text-decoration: none; font-weight: 700; font-size: 16px; }
.brand svg { width: 28px; height: 28px; }
.logo-bg { fill: var(--accent); }
.logo-fg { fill: none; stroke: var(--accent-fg); stroke-width: 2.6; stroke-linecap: round; stroke-linejoin: round; }
.room-chip { display: flex; align-items: center; gap: 6px; padding: 3px 4px 3px 12px; border: 1px solid var(--border); border-radius: 999px; font-size: 14px; }
.room-chip strong { font-family: var(--mono); letter-spacing: .08em; }
.timer { display: flex; align-items: center; gap: 8px; padding: 3px 6px 3px 12px; border-radius: 999px; background: var(--panel-2); border: 1px solid var(--border); }
.timer-time { font: 600 18px/1 var(--mono); min-width: 64px; text-align: center; font-variant-numeric: tabular-nums; }
.timer.paused .timer-time { color: var(--muted); }
.timer.warn { background: var(--warn-soft); border-color: var(--warn); }
.timer.warn .timer-time { color: var(--warn); }
.timer.over { background: var(--bad-soft); border-color: var(--bad); }
.timer.over .timer-time { color: var(--bad); }
.timer-controls { display: inline-flex; gap: 4px; align-items: center; }
.people { display: flex; gap: 6px; flex-wrap: wrap; }
.person { display: inline-flex; align-items: center; gap: 6px; padding: 3px 10px 3px 6px; border-radius: 999px; background: var(--panel-2); border: 1px solid var(--border); font-size: 13px; }
.person .dot { width: 10px; height: 10px; border-radius: 50%; background: var(--pc); box-shadow: 0 0 0 2px color-mix(in srgb, var(--pc) 25%, transparent); }
.person .who { font-weight: 600; }
.person .what { color: var(--muted); }
.person.offline { opacity: .55; }
.person.offline .dot { background: transparent; border: 2px solid var(--pc); box-shadow: none; }
.person button { border: 0; background: none; color: var(--muted); cursor: pointer; padding: 0 0 0 2px; font-size: 15px; line-height: 1; }
.person button:hover { color: var(--bad); }
.conn { font-size: 13px; color: var(--warn); font-weight: 600; }
.c0 { --pc: var(--c0); } .c1 { --pc: var(--c1); } .c2 { --pc: var(--c2); } .c3 { --pc: var(--c3); }
.c4 { --pc: var(--c4); } .c5 { --pc: var(--c5); } .c6 { --pc: var(--c6); } .c7 { --pc: var(--c7); }

/* ---------- home ---------- */
.home { max-width: 1040px; width: 100%; margin: 0 auto; padding: 56px 16px 40px; }
.hero { text-align: center; margin-bottom: 36px; }
.hero h1 { font-size: clamp(28px, 4vw, 40px); letter-spacing: -.02em; }
.lead { color: var(--muted); font-size: 18px; max-width: 640px; margin: 14px auto 0; }
.home-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 20px; }
.card { background: var(--panel); border: 1px solid var(--border); border-radius: 14px; padding: 24px; box-shadow: var(--shadow); display: flex; flex-direction: column; gap: 14px; }
.card h2 { font-size: 20px; }
.card p { margin: 0; }
.card label { display: flex; flex-direction: column; gap: 6px; font-weight: 600; font-size: 14px; }
.card .btn { align-self: flex-start; margin-top: 4px; }
#joinCode { font-family: var(--mono); letter-spacing: .15em; text-transform: uppercase; }
.roles { border: 0; padding: 0; margin: 0; display: flex; gap: 18px; flex-wrap: wrap; }
.roles legend { font-weight: 600; font-size: 14px; margin-bottom: 6px; padding: 0; }
.card label.radio, .check { flex-direction: row; align-items: center; gap: 8px; font-weight: 500; }
.form-msg { color: var(--bad); font-size: 14px; min-height: 1em; }
.form-msg .btn { margin: 8px 0 0; }
.features { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 36px; }
.features div { display: flex; flex-direction: column; gap: 4px; padding: 4px; }
.features span { color: var(--muted); font-size: 14px; }

/* ---------- room layout ---------- */
.room { flex: 1; min-height: 0; display: grid; grid-template-columns: minmax(340px, 30%) 1fr; }
.side { display: flex; flex-direction: column; min-height: 0; border-right: 1px solid var(--border); background: var(--panel); }
.tabs { display: flex; gap: 2px; padding: 8px 10px 0; border-bottom: 1px solid var(--border); }
.tab { font: inherit; font-size: 14px; font-weight: 600; border: 0; background: none; color: var(--muted); padding: 8px 12px; border-bottom: 2px solid transparent; cursor: pointer; display: inline-flex; gap: 6px; align-items: center; }
.tab:hover { color: var(--fg); }
.tab.active { color: var(--fg); border-bottom-color: var(--accent); }
.tab.private-tab { color: var(--warn); }
.tabs.small { padding: 0; border: 0; }
.tabs.small .tab { padding: 6px 10px; font-size: 13px; }
.badge { background: var(--accent); color: var(--accent-fg); border-radius: 999px; font-size: 11px; padding: 0 6px; line-height: 17px; }
.pane { flex: 1; min-height: 0; overflow: auto; padding: 18px 20px 24px; }
.pane[data-pane="chat"] { display: flex; flex-direction: column; padding: 0; }

/* problem */
.problem h2 { font-size: 20px; margin-bottom: 8px; }
.problem-meta { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 14px; align-items: center; }
.diff { font-size: 12px; font-weight: 700; padding: 2px 8px; border-radius: 999px; }
.diff.Easy { color: var(--ok); background: var(--ok-soft); }
.diff.Medium { color: var(--warn); background: var(--warn-soft); }
.diff.Hard { color: var(--bad); background: var(--bad-soft); }
.topic { font-size: 12px; color: var(--muted); background: var(--panel-2); border: 1px solid var(--border); padding: 1px 8px; border-radius: 999px; }
.statement p { margin: 0 0 10px; }
.statement code, .ex code, .hint code { background: var(--panel-2); border: 1px solid var(--border); border-radius: 4px; padding: 0 4px; font-size: 13px; }
.ex { background: var(--panel-2); border: 1px solid var(--border); border-radius: 8px; padding: 10px 12px; margin: 10px 0; font-size: 13px; }
.ex-title { font-weight: 700; font-size: 13px; margin-bottom: 4px; }
.ex pre { margin: 0; white-space: pre-wrap; word-break: break-word; font-size: 13px; }
.ex .note { color: var(--muted); margin-top: 4px; }
.constraints { padding-left: 18px; color: var(--muted); font-size: 13px; }
.block { margin-top: 18px; }
.block h3 { font-size: 13px; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); margin-bottom: 8px; }
.empty-state { color: var(--muted); text-align: center; padding: 30px 10px; }
.empty-state strong { display: block; color: var(--fg); font-size: 16px; margin-bottom: 6px; }
.change-row { display: flex; justify-content: flex-end; margin-bottom: 8px; }

/* picker */
.picker { border: 1px solid var(--border); border-radius: var(--radius); margin-bottom: 18px; background: var(--panel-2); }
.picker-head { display: flex; flex-direction: column; gap: 4px; padding: 12px 14px; border-bottom: 1px solid var(--border); }
.picker-head .check { display: flex; font-size: 13px; color: var(--muted); }
.picker-list { max-height: 420px; overflow: auto; padding: 6px; }
.picker-group { font-size: 12px; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; padding: 8px 8px 4px; }
.pick { display: flex; width: 100%; text-align: left; justify-content: space-between; align-items: center; gap: 10px; font: inherit; font-size: 14px; background: none; border: 0; border-radius: 6px; padding: 7px 8px; color: var(--fg); cursor: pointer; }
.pick:hover { background: var(--accent-soft); }
.pick.current { background: var(--accent-soft); font-weight: 700; }
.pick small { color: var(--muted); font-size: 12px; text-align: right; }

/* private tab */
.private-note { background: var(--warn-soft); color: var(--fg); border: 1px solid var(--warn); border-radius: 8px; padding: 8px 12px; font-size: 13px; margin: 0 0 6px; }
.hint { margin: 0 0 6px; }
.solution pre, .code-view { background: var(--editor-bg); border: 1px solid var(--border); border-radius: 8px; padding: 10px 12px; overflow: auto; font-size: 13px; line-height: 1.5; margin: 8px 0 0; tab-size: 4; }
.solution summary { cursor: pointer; font-weight: 600; }
.seg { display: inline-flex; border: 1px solid var(--border-strong); border-radius: 8px; overflow: hidden; }
.seg-btn { font: inherit; font-size: 13px; font-weight: 600; border: 0; background: var(--panel); color: var(--muted); padding: 5px 12px; cursor: pointer; }
.seg-btn + .seg-btn { border-left: 1px solid var(--border-strong); }
.seg-btn.active { background: var(--accent-soft); color: var(--accent); }
.seg-btn:disabled { cursor: not-allowed; }
.hidden-tests { font-size: 13px; padding-left: 18px; margin: 0; }
.hidden-tests li { margin-bottom: 4px; }
.hidden-tests code { font-size: 12px; word-break: break-word; }
#notes { width: 100%; resize: vertical; font-size: 14px; }
.scores { display: grid; gap: 8px; }
.score-row { display: flex; align-items: center; justify-content: space-between; gap: 10px; font-size: 14px; }
.score-row .seg-btn { padding: 4px 9px; }

/* chat */
.chat-list { list-style: none; margin: 0; padding: 14px 16px; flex: 1; overflow: auto; display: flex; flex-direction: column; gap: 10px; }
.chat-list li { font-size: 14px; }
.chat-list .from { font-weight: 700; margin-right: 6px; color: var(--pc); }
.chat-list time { color: var(--faint); font-size: 12px; }
.chat-list .text { white-space: pre-wrap; word-break: break-word; }
.chat-form { display: flex; gap: 8px; padding: 10px; border-top: 1px solid var(--border); }
.chat-form input { flex: 1; min-width: 0; }

/* ---------- work area ---------- */
.work { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.toolbar { display: flex; align-items: center; gap: 10px; padding: 8px 12px; border-bottom: 1px solid var(--border); background: var(--panel); flex-wrap: wrap; }
.sync { font-size: 13px; color: var(--muted); display: inline-flex; align-items: center; gap: 6px; }
.sync::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--ok); }
.sync.sending::before { background: var(--warn); }
.sync.offline::before { background: var(--bad); }
.role-tag { font-size: 13px; color: var(--muted); }
.editor { flex: 1; min-height: 160px; }
.output { height: 34%; min-height: 150px; border-top: 1px solid var(--border); background: var(--panel); display: flex; flex-direction: column; }
.output-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 4px 12px; border-bottom: 1px solid var(--border); }
.run-summary { font-size: 13px; color: var(--muted); }
.run-summary strong.ok { color: var(--ok); }
.run-summary strong.bad { color: var(--bad); }
.out-pane { flex: 1; overflow: auto; padding: 10px 12px; font-size: 13px; }
.out-pane .empty { margin: 6px 0; }
.case { display: grid; grid-template-columns: 22px 1fr; gap: 2px 8px; padding: 8px 10px; border: 1px solid var(--border); border-radius: 8px; margin-bottom: 6px; background: var(--panel-2); }
.case .mark { font-weight: 800; font-size: 15px; line-height: 20px; }
.case.pass .mark { color: var(--ok); }
.case.fail .mark { color: var(--bad); }
.case.pending .mark { color: var(--faint); }
.case-title { font-weight: 700; }
.case-title small { font-weight: 500; color: var(--muted); margin-left: 6px; }
.case dl { grid-column: 2; display: grid; grid-template-columns: auto 1fr; gap: 1px 10px; margin: 2px 0 0; }
.case dt { color: var(--muted); }
.case dd { margin: 0; font-family: var(--mono); font-size: 12.5px; white-space: pre-wrap; word-break: break-word; }
.case dd.err { color: var(--bad); }
.case dd.plain { font-family: var(--sans); font-size: 13px; }
.run-error { color: var(--bad); background: var(--bad-soft); border-radius: 8px; padding: 8px 10px; font-family: var(--mono); font-size: 12.5px; white-space: pre-wrap; margin: 0 0 8px; }
.run-note { color: var(--muted); margin: 0 0 8px; }
.log { font-family: var(--mono); font-size: 12.5px; white-space: pre-wrap; word-break: break-word; padding: 2px 0; border-bottom: 1px dashed var(--border); }
.log.warn { color: var(--warn); }
.log.error { color: var(--bad); }
.log .from { color: var(--faint); margin-right: 8px; }

/* ---------- the editor ---------- */
.ed { display: flex; height: 100%; background: var(--editor-bg); overflow: hidden; position: relative; }
.ed-gutter { width: 52px; flex: none; overflow: hidden; border-right: 1px solid var(--border); background: var(--editor-bg); }
.ed-lines { margin: 0; padding: 12px 10px 12px 0; text-align: right; color: var(--gutter); font: var(--code-size)/var(--code-lh) var(--mono); user-select: none; }
.ed-code { position: relative; flex: 1; min-width: 0; overflow: hidden; }
.ed-hl, .ed-input { margin: 0; padding: 12px 16px; font: var(--code-size)/var(--code-lh) var(--mono); tab-size: 4; white-space: pre; letter-spacing: 0; word-spacing: 0; font-variant-ligatures: none; }
.ed-hl { position: absolute; top: 0; left: 0; min-width: 100%; pointer-events: none; color: var(--fg); will-change: transform; }
.ed-input { position: absolute; inset: 0; width: 100%; height: 100%; resize: none; border: 0; border-radius: 0; background: transparent; color: transparent; caret-color: var(--fg); overflow: auto; outline: none; box-shadow: none; }
.ed-input:focus { box-shadow: none; }
.ed-input::selection { background: var(--selection); color: transparent; }
.ed.ro .ed-input { caret-color: transparent; }
.t-keyword { color: var(--t-keyword); }
.t-string { color: var(--t-string); }
.t-number { color: var(--t-number); }
.t-comment { color: var(--t-comment); font-style: italic; }
.t-function { color: var(--t-function); }
.t-literal { color: var(--t-literal); }
.t-builtin { color: var(--t-builtin); }
.t-type { color: var(--t-type); }
.t-decorator { color: var(--t-decorator); }
/* other people's selections and cursors */
.rs { background: color-mix(in srgb, var(--pc) 24%, transparent); border-radius: 2px; }
.rc { display: inline-block; position: relative; width: 0; height: var(--code-lh); vertical-align: top; }
.rc::before { content: ""; position: absolute; left: -1px; top: 0; bottom: 0; border-left: 2px solid var(--pc); }
.rc::after { content: attr(data-name); position: absolute; left: -1px; bottom: 100%; font: 600 11px/16px var(--sans); color: #fff; background: var(--pc); padding: 0 5px; border-radius: 4px 4px 4px 0; white-space: nowrap; opacity: 0; transition: opacity .4s; z-index: 1; }
.rc.fresh::after { opacity: .95; transition: none; }
.rc.first::after { bottom: auto; top: 100%; border-radius: 0 4px 4px 4px; }

/* ---------- overlay, dialog, toasts ---------- */
.overlay { position: fixed; inset: 0; background: rgba(10, 14, 22, .45); display: grid; place-items: center; z-index: 50; padding: 16px; }
.overlay-card { background: var(--panel); border: 1px solid var(--border); border-radius: 14px; padding: 22px; max-width: 420px; box-shadow: var(--shadow); }
.overlay-card p { margin: 0 0 14px; }
.overlay-actions { display: flex; gap: 8px; justify-content: flex-end; }
.summary { border: 1px solid var(--border); border-radius: 14px; padding: 0; background: var(--panel); color: var(--fg); width: min(760px, calc(100vw - 32px)); box-shadow: var(--shadow); }
.summary::backdrop { background: rgba(10, 14, 22, .5); }
.summary-inner { padding: 22px 24px; display: flex; flex-direction: column; gap: 14px; max-height: calc(100vh - 60px); }
.summary-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 10px; }
.stat { background: var(--panel-2); border: 1px solid var(--border); border-radius: 10px; padding: 10px 12px; }
.stat span { display: block; font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: .05em; }
.stat strong { font-size: 18px; }
#summaryBody .code-view { max-height: 260px; }
.summary-actions { display: flex; gap: 8px; justify-content: flex-end; flex-wrap: wrap; }
.toasts { position: fixed; right: 16px; bottom: 16px; display: flex; flex-direction: column; gap: 8px; z-index: 60; max-width: min(380px, calc(100vw - 32px)); }
.toast { background: var(--fg); color: var(--bg); padding: 10px 14px; border-radius: 10px; font-size: 14px; box-shadow: var(--shadow); animation: pop .18s ease-out; }
.toast.warn { background: var(--warn); color: #1b1300; }
@keyframes pop { from { transform: translateY(6px); opacity: 0; } }

/* ---------- smaller screens (tablets) ---------- */
@media (max-width: 1180px) {
  .room { grid-template-columns: minmax(300px, 34%) 1fr; }
  .topbar { gap: 10px; }
  .person .what, .role-tag { display: none; }
  .features { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 900px) {
  body { min-height: 100%; height: auto; }
  .room { display: flex; flex-direction: column; }
  .side { border-right: 0; border-bottom: 1px solid var(--border); max-height: 42vh; }
  .work { min-height: 72vh; }
  .output { height: 30vh; }
  .home { padding-top: 32px; }
}
@media (max-width: 560px) {
  .topbar { padding: 8px 12px; }
  .brand span { display: none; }
  .timer-controls select { display: none; }
  .features { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) { .toast { animation: none; } }

/* ---------- community problems in the room ---------- */
.community { font-size: 12px; font-weight: 600; color: var(--c3); background: color-mix(in srgb, var(--c3) 12%, transparent); border: 1px solid color-mix(in srgb, var(--c3) 35%, transparent); padding: 1px 8px; border-radius: 999px; }
.community.small { font-size: 11px; padding: 0 6px; margin-left: 8px; vertical-align: 1px; }
.pre-line { white-space: pre-line; }

/* ---------- home: submit a problem ---------- */
.contribute { margin-top: 36px; display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap; background: var(--panel); border: 1px solid var(--border); border-radius: 14px; padding: 20px 24px; }
.contribute h2 { font-size: 18px; margin-bottom: 4px; }
.contribute p { margin: 0; }
.contribute-actions { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
a.btn { text-decoration: none; }

/* ---------- submit / status / review pages ---------- */
body.page { height: auto; min-height: 100%; }
.page-name { color: var(--muted); font-weight: 600; font-size: 14px; padding-left: 12px; border-left: 1px solid var(--border); }
.who-chip { font-size: 13px; color: var(--muted); }
.page-main { max-width: 1120px; width: 100%; margin: 0 auto; padding: 28px 16px 64px; display: flex; flex-direction: column; gap: 18px; }
.page-intro h1, .signin h1, .detail-head h1 { font-size: clamp(24px, 3vw, 30px); letter-spacing: -.01em; }
.lead-sm { color: var(--muted); font-size: 16px; max-width: 820px; margin: 10px 0; }
.small { font-size: 13px; }
.linkish { font: inherit; background: none; border: 0; padding: 0; color: var(--accent); cursor: pointer; text-decoration: underline; }
.row { display: flex; align-items: center; gap: 10px; }
.row.space { justify-content: space-between; }
.row.wrap { flex-wrap: wrap; }
.problem-form { display: flex; flex-direction: column; gap: 18px; }
.pf-card { background: var(--panel); border: 1px solid var(--border); border-radius: 14px; padding: 20px 22px; box-shadow: var(--shadow); display: flex; flex-direction: column; gap: 14px; min-width: 0; }
.pf-card h2 { font-size: 17px; }
.pf-card h3 { font-size: 13px; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); margin: 4px 0 0; }
.pf-card.private { border-color: color-mix(in srgb, var(--warn) 45%, var(--border)); }
.small-h { font-size: 13px !important; text-transform: uppercase; letter-spacing: .06em; }
.pf-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 14px; }
.pf-split { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.field-label { font-weight: 600; font-size: 14px; }
.help { color: var(--muted); font-size: 13px; margin: 0; }
.help code, .statement.preview code { background: var(--panel-2); border: 1px solid var(--border); border-radius: 4px; padding: 0 4px; font-size: 12.5px; }
.field textarea, .field input, .field select { width: 100%; }
.field select { padding: 8px 10px; font-size: 14px; }
.statement.preview { background: var(--panel-2); border: 1px dashed var(--border-strong); border-radius: 8px; padding: 10px 12px; min-height: 120px; overflow: auto; max-height: 260px; }
.code-input, input.mono { font-family: var(--mono); font-size: 13px; tab-size: 2; }
textarea.code-input { white-space: pre; overflow: auto; line-height: 1.5; resize: vertical; }
input.bad, textarea.bad, select.bad { border-color: var(--bad) !important; background: var(--bad-soft); }
.params { display: flex; flex-direction: column; gap: 8px; align-items: flex-start; }
.param-row { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.param-row input { width: 180px; font-family: var(--mono); }
.param-row select { padding: 8px 10px; font-size: 14px; }
.case-table { display: flex; flex-direction: column; gap: 6px; overflow-x: auto; padding-bottom: 2px; }
.case-table > .btn { align-self: flex-start; }
.case-row { display: grid; grid-template-columns: var(--grid); gap: 6px; align-items: center; min-width: min-content; }
.case-row input { padding: 6px 8px; min-width: 0; }
.case-row.head { font-size: 12px; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
.case-row .num { color: var(--faint); font-size: 12px; text-align: right; }
.case-row .th { font-family: var(--mono); text-transform: none; letter-spacing: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.json-mode { display: flex; flex-direction: column; gap: 8px; }
.json-mode textarea { width: 100%; }
details.starter summary { cursor: pointer; font-weight: 600; font-size: 14px; color: var(--muted); }
details.starter[open] summary { margin-bottom: 10px; }
.pf-errors { background: var(--bad-soft); border: 1px solid var(--bad); border-radius: 8px; padding: 10px 14px; font-size: 14px; }
.pf-errors ul { margin: 6px 0 0; padding-left: 18px; }
.check-status { margin: 0; font-weight: 600; font-size: 14px; color: var(--muted); }
.check-status.ok { color: var(--ok); }
.check-status.bad { color: var(--bad); }
.check-status.warn { color: var(--warn); }
.check-results { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 6px; font-size: 13px; }
.check-results .case { margin: 0; }
.submit-bar { display: flex; align-items: center; justify-content: flex-end; gap: 14px; flex-wrap: wrap; position: sticky; bottom: 0; background: color-mix(in srgb, var(--bg) 92%, transparent); backdrop-filter: blur(6px); padding: 12px 0; border-top: 1px solid var(--border); z-index: 5; }
.submit-bar p { margin: 0; }
.submit-bar p:first-child { margin-right: auto; }
.submit-bar .form-msg:empty { display: none; }
.btn.big { padding: 11px 20px; font-size: 15px; }
.thanks { border-color: var(--ok); }
.thanks p { margin: 0; }
.link-box { display: flex; gap: 8px; flex-wrap: wrap; }
.link-box input { flex: 1; min-width: 220px; font-family: var(--mono); font-size: 13px; }
.chip { display: inline-block; font-size: 12px; font-weight: 700; padding: 3px 10px; border-radius: 999px; white-space: nowrap; }
.chip.pending { color: var(--accent); background: var(--accent-soft); }
.chip.changes { color: var(--warn); background: var(--warn-soft); }
.chip.rejected { color: var(--bad); background: var(--bad-soft); }
.chip.approved { color: var(--ok); background: var(--ok-soft); }
.status-line { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin: 6px 0 12px; }
.review-note { background: var(--warn-soft); border: 1px solid var(--warn); border-radius: 10px; padding: 10px 14px; margin-bottom: 12px; }
.review-note p { margin: 4px 0 0; }
.problem.readonly .block { margin-top: 14px; }
/* review page */
.signin { max-width: 560px; margin: 24px auto 0; }
.signin p { margin: 0; }
.signin-form { display: flex; flex-direction: column; gap: 12px; }
.signin-form .btn { align-self: flex-start; }
.review-head { display: flex; align-items: flex-end; gap: 12px; justify-content: space-between; flex-wrap: wrap; border-bottom: 1px solid var(--border); margin-bottom: 14px; }
.review-tabs { border-bottom: 0; padding: 0; flex-wrap: wrap; }
.review-head > .btn { margin-bottom: 8px; }
.count { font-size: 12px; background: var(--panel-2); border: 1px solid var(--border); border-radius: 999px; padding: 0 7px; color: var(--muted); }
.count.hot { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }
.review-list { display: flex; flex-direction: column; gap: 8px; }
.review-row { display: flex; justify-content: space-between; align-items: center; gap: 14px; width: 100%; text-align: left; font: inherit; color: var(--fg); background: var(--panel); border: 1px solid var(--border); border-radius: 12px; padding: 14px 16px; cursor: pointer; }
.review-row:hover { border-color: var(--accent); }
.rr-main { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.rr-meta { display: flex; gap: 6px; flex-wrap: wrap; align-items: center; font-size: 13px; }
.rr-side { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; justify-content: flex-end; text-align: right; }
.detail-head p { margin: 2px 0; }
.history { list-style: none; padding: 0; margin: 4px 0 0; font-size: 13px; display: flex; flex-direction: column; gap: 4px; }
#detail { display: flex; flex-direction: column; gap: 18px; }
#detail > p { margin: 0; }
.actions-card { border-color: var(--accent); }
.actions-card textarea { width: 100%; }
.actions-card p { margin: 0; }
.btn.danger-text { color: var(--bad); }
.reviewers-table { width: 100%; border-collapse: collapse; font-size: 14px; }
.reviewers-table th { text-align: left; font-size: 12px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); padding: 6px 8px; border-bottom: 1px solid var(--border); }
.reviewers-table td { padding: 8px; border-bottom: 1px solid var(--border); }
.reviewers-table td.actions { text-align: right; }
.invite-form { align-items: flex-end; }
.invite-form .field input { width: 220px; }
.invite-result { background: var(--ok-soft); border: 1px solid var(--ok); border-radius: 10px; padding: 12px 14px; display: flex; flex-direction: column; gap: 6px; }
.invite-result p { margin: 0; }
#reviewers { display: flex; flex-direction: column; gap: 18px; }
@media (max-width: 900px) {
  .pf-split { grid-template-columns: 1fr; }
  .page-main { padding-top: 18px; }
}
@media (max-width: 560px) {
  .pf-card { padding: 16px 14px; }
  .page-name { display: none; }
  .review-row { flex-direction: column; align-items: flex-start; }
  .rr-side { justify-content: flex-start; text-align: left; }
  .reviewers-table { display: block; overflow-x: auto; }
}
.field .param-row input { width: 180px; }
.field .param-row select { width: auto; }
.case-row .th.plain { font-family: var(--sans); text-transform: uppercase; letter-spacing: .04em; }
.json-mode .form-msg:empty { display: none; }
.review-note.ok { background: var(--ok-soft); border-color: var(--ok); }