:root {
  --bg: #f4f3ef;
  --card: #ffffff;
  --ink: #1c1c1a;
  --muted: #6d6c66;
  --line: #e2e0d8;
  --accent: #5b3fa8;
  --on-accent: #ffffff;
  --peach: #c4622d;
  --green: #2f7d4f;
  --blue: #2f5fa8;
  --sel: #efeaf9;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.06);
  --tabbar: 56px;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #141417;
    --card: #1d1d22;
    --ink: #e8e6df;
    --muted: #9a988f;
    --line: #2d2d33;
    --accent: #b9a2f2;
    --on-accent: #141417;
    --peach: #f0a070;
    --green: #7fcf98;
    --blue: #8db4f5;
    --sel: #2a2440;
    --shadow: none;
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --bg: #141417;
  --card: #1d1d22;
  --ink: #e8e6df;
  --muted: #9a988f;
  --line: #2d2d33;
  --accent: #b9a2f2;
  --on-accent: #141417;
  --peach: #f0a070;
  --green: #7fcf98;
  --blue: #8db4f5;
  --sel: #2a2440;
  --shadow: none;
  color-scheme: dark;
}

* { box-sizing: border-box; }

html { background: var(--bg); -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.5 -apple-system, system-ui, sans-serif;
  -webkit-tap-highlight-color: transparent;
}

.screen {
  max-width: 480px;
  min-height: 100dvh;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: calc(env(safe-area-inset-top) + 10px) calc(env(safe-area-inset-right) + 16px) calc(var(--tabbar) + env(safe-area-inset-bottom) + 20px) calc(env(safe-area-inset-left) + 16px);
}

.top { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; padding: 4px 8px; }
.top b { font-size: 22px; min-width: 0; overflow-wrap: anywhere; }
.top span { color: var(--muted); font-size: 13px; white-space: nowrap; }

.group { font-size: 12px; font-weight: 700; letter-spacing: 0.06em; text-transform: uppercase; padding: 4px 8px 0; margin: 0; }
.g-peach { color: var(--peach); }
.g-blue { color: var(--blue); }
.g-green { color: var(--green); }
.g-muted { color: var(--muted); }

.task {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px 14px;
  box-shadow: var(--shadow);
  display: grid;
  gap: 4px;
  color: inherit;
  text-decoration: none;
  min-width: 0;
  overflow-wrap: anywhere;
}
a.task:active { background: var(--sel); }
.task .name { font-weight: 650; }
.task .meta, .meta { color: var(--muted); font-size: 13px; }
.you { font-size: 14px; }
.you b { color: var(--peach); font-weight: 600; }
.machine { display: inline-block; font-size: 12px; font-weight: 400; color: var(--muted); border: 1px solid var(--line); border-radius: 999px; padding: 0 8px; margin-left: 6px; }
.asleep { opacity: 0.55; }

.btn {
  display: block;
  width: 100%;
  min-height: 46px;
  text-align: center;
  border-radius: 12px;
  padding: 12px;
  font: inherit;
  font-weight: 600;
  border: 1px solid var(--line);
  background: var(--card);
  color: var(--ink);
  text-decoration: none;
  cursor: pointer;
}
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.btn.off, .btn:disabled { opacity: 0.45; cursor: default; }

.code { font: 600 34px ui-monospace, Menlo, monospace; letter-spacing: 0.12em; text-align: center; padding: 18px 0; }
.center { text-align: center; color: var(--muted); font-size: 14px; padding: 0 12px; }
.center.left { text-align: left; padding: 0 8px; }
.center b { color: var(--ink); }
.ok, .task .meta.ok { color: var(--green); }
.warn, .task .meta.warn, .center.warn { color: var(--peach); }
.link { color: var(--accent); text-decoration: none; padding: 8px 12px; }
.mono { font-family: ui-monospace, Menlo, monospace; font-size: 13px; }
.pad { padding-left: 8px; padding-right: 8px; }

.sec { font-size: 12px; font-weight: 700; letter-spacing: 0.06em; color: var(--muted); text-transform: uppercase; border-bottom: 1px solid var(--line); padding-bottom: 4px; margin: 6px 0 0; }
.plan { font-size: 14px; display: grid; gap: 6px; }

.chips { display: flex; gap: 6px; flex-wrap: wrap; }
.chip { border: 1px solid var(--line); border-radius: 999px; padding: 6px 12px; min-height: 36px; font: inherit; font-size: 14px; background: var(--card); color: var(--ink); cursor: pointer; }
.chip.on { background: var(--sel); border-color: var(--accent); color: var(--accent); font-weight: 600; }

.stack { display: grid; gap: 12px; margin: 0; }
.field input {
  width: 100%;
  border: 0;
  padding: 0;
  margin: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-size: 18px;
  outline: none;
}
.field:focus-within { border-color: var(--accent); }
.field .code-input { font: 600 22px ui-monospace, Menlo, monospace; letter-spacing: 0.1em; text-transform: uppercase; }
.field input::placeholder { color: var(--line); }

.hint { display: flex; gap: 8px; align-items: flex-start; background: var(--sel); border: 1px solid var(--line); border-radius: 14px; padding: 12px 14px; font-size: 14px; }
.hint .close { border: 0; background: transparent; color: var(--muted); font-size: 22px; line-height: 1; padding: 0 4px; min-width: 32px; min-height: 32px; cursor: pointer; }

.tabbar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  justify-content: space-around;
  border-top: 1px solid var(--line);
  background: var(--bg);
  padding: 0 env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left);
  font-size: 12px;
}
.tabbar a { flex: 1; max-width: 160px; min-height: var(--tabbar); display: flex; align-items: center; justify-content: center; color: var(--muted); text-decoration: none; }
.tabbar a.on { color: var(--accent); font-weight: 600; }
.pair-answer { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }