:root {
  color-scheme: light dark;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --bg: #f7f7f5;
  --panel: #ffffff;
  --line: #d7d7d2;
  --text: #151515;
  --muted: #5f6368;
  --brand: #1f2937;
  --accent: #2563eb;
  --code: #f1f1ee;
  --good: #15803d;
  --bad: #b91c1c;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
}

main {
  width: min(72rem, calc(100% - 2rem));
  margin: 0 auto;
  padding: 3rem 0;
  flex: 1;
}

main.narrow { width: min(44rem, calc(100% - 2rem)); }

.hero, .card {
  border: 1px solid var(--line);
  background: var(--panel);
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.06);
}

.hero { padding: clamp(1.25rem, 4vw, 2.5rem); }
.card { padding: 1.25rem; margin-top: 1rem; }
main.narrow .card { padding: 1.5rem; }

.badge {
  display: inline-flex;
  gap: 0.5rem;
  align-items: center;
  padding: 0.4rem 0.7rem;
  border: 1px solid var(--line);
  background: var(--code);
  color: var(--muted);
  font-weight: 700;
}

.status-badge { color: var(--good); font-weight: 800; }

h1 {
  margin: 0.75rem 0 0.5rem;
  font-size: clamp(2.25rem, 7vw, 4.75rem);
  letter-spacing: -0.055em;
  line-height: 1;
}

main.narrow h1 { font-size: 2rem; letter-spacing: -0.04em; }
h2 { margin-top: 0; }
p { color: var(--muted); line-height: 1.6; }
a { color: inherit; }

form {
  display: grid;
  grid-template-columns: 1.4fr 1fr 0.45fr auto;
  gap: 0.75rem;
  align-items: end;
  margin-top: 1.5rem;
}

label {
  display: grid;
  gap: 0.35rem;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 700;
}

input {
  width: 100%;
  border: 1px solid var(--line);
  padding: 0.85rem 0.95rem;
  background: #fff;
  color: var(--text);
  font: inherit;
}

.checks {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

.checks label {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.95rem;
}

.checks input { width: auto; }

button, .button-link {
  display: inline-block;
  border: 1px solid var(--brand);
  padding: 0.9rem 1.1rem;
  background: var(--brand);
  color: white;
  font-weight: 900;
  cursor: pointer;
  min-width: 8rem;
  text-align: center;
  text-decoration: none;
}

button:disabled { opacity: 0.65; cursor: wait; }

.status-row, .status {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  align-items: center;
}

.status {
  border-top: 1px solid var(--line);
  margin-top: 1.25rem;
  padding-top: 1.25rem;
}

#message { font-weight: 800; }
.ok { color: var(--good); }
.err { color: var(--bad); }

.loading {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.85rem;
  align-items: center;
  margin: 0.9rem 0;
  padding: 0.85rem;
  border: 1px solid var(--line);
  background: linear-gradient(90deg, var(--code), var(--panel));
}

.loading[hidden] { display: none; }

.spinner {
  width: 2rem;
  height: 2rem;
  border: 3px solid var(--line);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.75s linear infinite;
}

.progress {
  height: 0.45rem;
  margin-top: 0.55rem;
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--panel);
}

.progress span {
  display: block;
  width: 0;
  height: 100%;
  background: var(--accent);
  transition: width 220ms ease;
}

@keyframes spin { to { transform: rotate(360deg); } }

.tree {
  margin: 1rem 0 0;
  padding: 0;
  list-style: none;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.93rem;
}

.tree-info {
  margin: 0.75rem 0 0.5rem;
  padding: 0.65rem 0.75rem;
  border: 1px solid var(--line);
  background: var(--code);
  font-weight: 700;
}

.filter {
  display: block;
  margin: 0.75rem 0;
}

.tree ul {
  margin: 0.25rem 0 0.25rem 1.2rem;
  padding-left: 1rem;
  border-left: 1px dashed var(--line);
  list-style: none;
}

.tree summary {
  cursor: pointer;
  list-style-position: outside;
}

.node {
  display: inline-flex;
  gap: 0.45rem;
  align-items: center;
  margin: 0.18rem 0;
  padding: 0.35rem 0.5rem;
  border: 1px solid var(--line);
  background: var(--code);
}

.node.repeated { border-style: dashed; }
.node.cyclic { border-color: var(--bad); }
.badge.warn { color: var(--bad); }
.badge.repeat { color: var(--accent); }

.name { font-weight: 900; }
.version { color: var(--accent); }
.meta { color: var(--muted); font-size: 0.9rem; }

pre {
  max-height: 28rem;
  overflow: auto;
  padding: 1rem;
  border: 1px solid var(--line);
  background: var(--code);
}

footer {
  width: min(72rem, calc(100% - 2rem));
  margin: auto auto 0;
  padding: 0 0 1rem;
  color: var(--muted);
  font-size: 0.9rem;
}

footer.narrow { width: min(44rem, calc(100% - 2rem)); }

@media (max-width: 760px) {
  form { grid-template-columns: 1fr; }
  button { width: 100%; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111111;
    --panel: #181818;
    --line: #333333;
    --text: #f2f2f2;
    --muted: #b8b8b8;
    --code: #202020;
    --brand: #f2f2f2;
    --accent: #60a5fa;
    --good: #4ade80;
    --bad: #f87171;
  }

  input { background: #111111; }
  button, .button-link { background: var(--text); color: var(--bg); }
  .badge { background: var(--code); color: var(--muted); }
}