/* ── Reset / base ─────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0d1117;
  --bg-card:   #161b22;
  --bg-hover:  #1c2330;
  --border:    #30363d;
  --accent:    #238636;
  --accent-h:  #2ea043;
  --text:      #e6edf3;
  --muted:     #8b949e;
  --link:      #58a6ff;
  --radius:    8px;
  --max-w:     760px;
}

html { font-size: 16px; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }

code {
  font-family: ui-monospace, "SFMono-Regular", Menlo, monospace;
  font-size: 0.875em;
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 1px 6px;
  border-radius: 4px;
}

/* ── Header ───────────────────────────────────────────── */
header {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  padding: 2.5rem 1.5rem 2rem;
  text-align: center;
}

header h1 {
  font-size: 2.25rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 0.5rem;
}

.tagline {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.5;
}

/* ── Main ─────────────────────────────────────────────── */
main {
  flex: 1;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2rem 1.25rem;
  width: 100%;
}

/* ── Steps ────────────────────────────────────────────── */
.step {
  margin-bottom: 2.5rem;
}

.step h2 {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--text);
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.6rem;
  height: 1.6rem;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 700;
  flex-shrink: 0;
}

/* ── Board cards ──────────────────────────────────────── */
.board-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(155px, 1fr));
  gap: 0.75rem;
}

.board-card {
  cursor: pointer;
  display: block;
}

.board-card input[type="radio"] {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.card-body {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
  transition: border-color 0.15s, background 0.15s;
  height: 100%;
}

.board-card:hover .card-body {
  background: var(--bg-hover);
  border-color: #58a6ff55;
}

.board-card.selected .card-body {
  border-color: var(--accent);
  background: #1a2e1f;
}

.board-name {
  font-weight: 600;
  font-size: 0.9rem;
  line-height: 1.35;
  margin-bottom: 0.35rem;
}

.board-chip {
  color: var(--muted);
  font-size: 0.78rem;
}

.board-untested {
  font-size: 0.72rem;
  color: #e3b341;
  margin-top: 0.3rem;
}

/* ── Flash row ────────────────────────────────────────── */
.hint {
  color: var(--muted);
  font-size: 0.875rem;
  margin-bottom: 1.25rem;
}

.flash-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.install-btn {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  padding: 0.65rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}

.install-btn:hover { background: var(--accent-h); }

.status-line {
  color: var(--muted);
  font-size: 0.8rem;
  margin-top: 0.6rem;
}

.channel-link {
  margin-top: 0.4rem;
  font-size: 0.82rem;
}
.channel-link a { color: var(--link); }

/* ── Channel cards ────────────────────────────────────── */
.channel-row {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 0.5rem;
}

.channel-card {
  cursor: pointer;
  display: block;
  min-width: 160px;
}

.channel-card input[type="radio"] {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.channel-body {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.75rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  transition: border-color 0.15s, background 0.15s;
}

.channel-card:hover .channel-body {
  background: var(--bg-hover);
  border-color: #58a6ff55;
}

.channel-card.selected .channel-body {
  border-color: var(--accent);
  background: #1a2e1f;
}

.channel-name {
  font-weight: 600;
  font-size: 0.9rem;
}

.channel-badge {
  font-size: 0.72rem;
  padding: 1px 6px;
  border-radius: 10px;
  font-weight: 600;
}
.badge-stable { background: #1f6feb44; color: #58a6ff; }
.badge-dev    { background: #6e40c944; color: #bc8cff; }

.channel-ver {
  font-size: 0.78rem;
  color: var(--muted);
  margin-left: auto;
}

/* ── First use steps ──────────────────────────────────── */
.step ol {
  padding-left: 1.35rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.step ol li { margin-bottom: 0.35rem; }
.step ol strong { color: var(--text); }
.step > p { color: var(--muted); font-size: 0.9rem; }
.step > p a { color: var(--link); }

/* ── Footer ───────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 1.5rem 1rem;
  color: var(--muted);
  font-size: 0.85rem;
}

footer p + p { margin-top: 0.4rem; }
footer .small { font-size: 0.78rem; }
footer a { color: var(--muted); }
footer a:hover { color: var(--link); text-decoration: underline; }

/* ── Responsive ───────────────────────────────────────── */
@media (max-width: 500px) {
  header h1 { font-size: 1.75rem; }
  .board-grid { grid-template-columns: 1fr 1fr; }
}

/* ── Back link ────────────────────────────────────────── */
.back {
  display: inline-block;
  color: var(--muted);
  font-size: 0.85rem;
  margin-bottom: 0.75rem;
  text-decoration: none;
}
.back:hover { color: var(--link); }