:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-2: #f0f2f5;
  --border: #dde1e7;
  --text: #1c2330;
  --muted: #5b6576;
  --accent: #2456d6;
  --accent-text: #ffffff;
  --ok: #1f7a45;
  --ok-bg: #e5f5ec;
  --bad: #b3261e;
  --bad-bg: #fbe9e7;
  --warn: #8a5a00;
  --warn-bg: #fff4d6;
  --mono: ui-monospace, "Cascadia Code", Consolas, "Liberation Mono", monospace;
  --radius: 10px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #11151c;
    --surface: #1a1f29;
    --surface-2: #222835;
    --border: #2f3746;
    --text: #e6e9ef;
    --muted: #9aa4b5;
    --accent: #6f98ff;
    --accent-text: #0c1020;
    --ok: #62d394;
    --ok-bg: #173325;
    --bad: #ff8a80;
    --bad-bg: #3a1c1a;
    --warn: #f2c35b;
    --warn-bg: #3a2f14;
  }
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
header.top {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}
header.top .inner, main {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 16px;
}
header.top .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 60px;
}
header.top h1 { font-size: 18px; margin: 0; }
header.top nav a { margin-left: 16px; text-decoration: none; color: var(--muted); font-size: 14px; }
header.top nav a.active { color: var(--text); font-weight: 600; }
main { padding-top: 24px; padding-bottom: 64px; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 20px;
}
.card h2 { margin: 0 0 4px; font-size: 17px; }
.step { color: var(--muted); font-size: 13px; text-transform: uppercase; letter-spacing: .06em; margin-bottom: 6px; }
.muted { color: var(--muted); }
.small { font-size: 13px; }

.assignments { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 12px; margin-top: 12px; }
.assignment {
  text-align: left;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface-2);
  color: var(--text);
  padding: 14px;
  cursor: pointer;
  font: inherit;
}
.assignment[aria-pressed="true"] { border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent) inset; }
.assignment strong { display: block; margin-bottom: 4px; }

.meta { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0; }
.chip {
  display: inline-block;
  padding: 2px 10px;
  border-radius: 999px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  font-size: 13px;
}
.chip.ok { background: var(--ok-bg); color: var(--ok); border-color: transparent; }
.chip.bad { background: var(--bad-bg); color: var(--bad); border-color: transparent; }
.chip.warn { background: var(--warn-bg); color: var(--warn); border-color: transparent; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  padding: 8px 14px;
  border-radius: 8px;
  font: inherit;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
}
.btn.primary { background: var(--accent); color: var(--accent-text); border-color: var(--accent); }
.btn:disabled { opacity: .55; cursor: not-allowed; }
.row { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }

form .grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 14px; }
label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 4px; }
input[type=text], input[type=password], select {
  width: 100%;
  padding: 9px 11px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  color: var(--text);
  font: inherit;
}
.drop {
  margin-top: 14px;
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 22px;
  text-align: center;
  color: var(--muted);
}
.drop.over { border-color: var(--accent); color: var(--text); }
.drop input { display: none; }

.alert { padding: 12px 14px; border-radius: 8px; margin: 12px 0; }
.alert.bad { background: var(--bad-bg); color: var(--bad); }
.alert.ok { background: var(--ok-bg); color: var(--ok); }
.alert.warn { background: var(--warn-bg); color: var(--warn); }

.score { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.score .big { font-size: 44px; font-weight: 700; line-height: 1; }

details.test {
  border: 1px solid var(--border);
  border-radius: 8px;
  margin: 8px 0;
  background: var(--surface);
}
details.test summary {
  cursor: pointer;
  padding: 10px 12px;
  display: flex;
  justify-content: space-between;
  gap: 10px;
  list-style: none;
}
details.test summary::-webkit-details-marker { display: none; }
details.test .body { padding: 0 12px 12px; }
.io { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 10px; }
pre {
  margin: 4px 0 0;
  padding: 10px;
  background: var(--surface-2);
  border-radius: 6px;
  font: 13px/1.45 var(--mono);
  font-variant-ligatures: none; /* show "->" as typed, not as an arrow glyph */
  font-feature-settings: "liga" 0, "calt" 0;
  overflow-x: auto;
  white-space: pre;
}
.hidden-list { display: flex; flex-wrap: wrap; gap: 8px; }

table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td { text-align: left; padding: 8px; border-bottom: 1px solid var(--border); vertical-align: top; }
th { color: var(--muted); font-weight: 600; font-size: 13px; }
.table-wrap { overflow-x: auto; }

.spinner {
  width: 16px; height: 16px;
  border: 2px solid currentColor;
  border-right-color: transparent;
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
[hidden] { display: none !important; }