:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --border: #e2e8f0;
  --border-strong: #cbd5e1;
  --shadow: 0 10px 30px rgba(2, 6, 23, 0.08);
  --radius: 14px;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Ubuntu, Cantarell, "Helvetica Neue", Arial, sans-serif;
  --focus: 0 0 0 3px rgba(15, 23, 42, 0.16);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0f14;
    --surface: #0f1620;
    --text: rgba(255, 255, 255, 0.92);
    --muted: rgba(255, 255, 255, 0.70);
    --border: rgba(255, 255, 255, 0.10);
    --border-strong: rgba(255, 255, 255, 0.18);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.45);
    --focus: 0 0 0 3px rgba(255, 255, 255, 0.18);
  }
}

* { box-sizing: border-box; }
html, body { height: 100%; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--text);
  background: var(--bg);
}

a { color: inherit; }
a:focus-visible { outline: none; box-shadow: var(--focus); border-radius: 8px; }

.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 28px 16px 52px;
}

.topbar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.title {
  margin: 0;
  font-size: 1.85rem;
  letter-spacing: -0.02em;
  line-height: 1.1;
}

.subtitle {
  margin: 10px 0 0;
  color: var(--muted);
  max-width: 78ch;
  line-height: 1.55;
  font-size: 1rem;
}

.badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
  margin-top: 2px;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  box-shadow: 0 1px 0 rgba(2, 6, 23, 0.04);
  font-size: 0.86rem;
  color: var(--muted);
  white-space: nowrap;
}

.badge svg {
  width: 16px;
  height: 16px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.card-header {
  padding: 18px 18px 8px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.card-header h2 {
  margin: 0;
  font-size: 1.12rem;
  letter-spacing: -0.01em;
}

.card-header svg {
  width: 22px;
  height: 22px;
  flex: 0 0 auto;
  color: var(--muted);
}

.card-body {
  padding: 0 18px 18px;
  color: var(--muted);
  line-height: 1.6;
}

.grid {
  display: block;
  margin-top: 14px;
}

.grid > .panel {
  margin-bottom: 16px;
}

.grid > .panel:last-child {
  margin-bottom: 0;
}

@media (min-width: 860px) {
  .grid {
    grid-template-columns: 1.2fr 0.8fr;
    align-items: start;
  }
}

.panel {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: transparent;
  overflow: hidden;
}

.panel-title {
  padding: 12px 12px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 600;
  font-size: 0.98rem;
  background: rgba(2, 6, 23, 0.02);
}

@media (prefers-color-scheme: dark) {
  .panel-title { background: rgba(255, 255, 255, 0.03); }
}

.panel-title svg {
  width: 18px;
  height: 18px;
  color: var(--muted);
}

.panel-body {
  padding: 12px 12px;
}

.steps {
  display: grid;
  gap: 14px;
  margin-top: 10px;
}

.step-label {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 600;
  margin-bottom: 8px;
}

.step-label svg {
  width: 18px;
  height: 18px;
  color: var(--muted);
}

.small {
  font-size: 0.95rem;
  color: var(--muted);
  margin: 0 0 10px;
}

/* Code block */
.codeblock {
  position: relative;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: rgba(2, 6, 23, 0.03);
  overflow: hidden;
}

@media (prefers-color-scheme: dark) {
  .codeblock { background: rgba(255, 255, 255, 0.04); }
}

.codeblock pre {
  margin: 0;
  padding: 12px 12px;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 0.95rem;
  color: var(--text);
  line-height: 1.45;
  white-space: pre; /* do not wrap */
}

.codeblock pre::-webkit-scrollbar { height: 10px; }
.codeblock pre::-webkit-scrollbar-thumb {
  background: rgba(2, 6, 23, 0.18);
  border-radius: 999px;
}
@media (prefers-color-scheme: dark) {
  .codeblock pre::-webkit-scrollbar-thumb { background: rgba(255, 255, 255, 0.18); }
}

/* Copy button: hidden until hover OR focus-within */
.copy-btn {
  position: absolute;
  top: 8px;
  right: 8px;

  display: inline-flex;
  align-items: center;
  justify-content: center;

  padding: 8px;
  border-radius: 10px;
  border: 1px solid var(--border-strong);
  background: var(--surface);
  color: var(--muted);

  cursor: pointer;

  opacity: 0;
  pointer-events: none;
  transform: translateY(-2px);
  transition: opacity 0.15s ease, transform 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
}

.codeblock:hover .copy-btn,
.codeblock:focus-within .copy-btn {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.copy-btn:hover { color: var(--text); }
.copy-btn:focus-visible {
  outline: none;
  box-shadow: var(--focus);
  color: var(--text);
}

.copy-btn svg { width: 18px; height: 18px; }

.copy-status {
  position: absolute;
  top: 11px;
  right: 50px;
  font-size: 0.85rem;
  color: var(--muted);
  opacity: 0;
  transition: opacity 0.18s ease;
  user-select: none;
  pointer-events: none;
}

.codeblock.copied .copy-status { opacity: 1; }

.list {
  margin: 8px 0 0;
  padding-left: 18px;
  color: var(--muted);
}

.footer {
  margin-top: 16px;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--muted);
  text-align: center;
  box-shadow: 0 2px 0 rgba(2, 6, 23, 0.03);
}

/* Inline code */
code.inline {
  font-family: var(--mono);
  font-size: 0.95em;
  padding: 2px 6px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: rgba(2, 6, 23, 0.02);
  color: var(--text);
}

@media (prefers-color-scheme: dark) {
  code.inline { background: rgba(255, 255, 255, 0.04); }
}

/* Responsive: stack topbar on small screens */
@media (max-width: 720px) {
  .topbar { flex-direction: column; }
  .badges { justify-content: flex-start; }
}