:root {
  --bg: #f4f6f8;
  --surface: #ffffff;
  --text: #17191c;
  --muted: #5c6470;
  --border: #dfe3e8;
  --accent: #0a8f6a;
  --accent-soft: #e2f5ee;
  --code-bg: #eef1f4;
  --warn-bg: #fff1f0;
  --warn-border: #e5484d;
  --todo-bg: #fff4c2;
  --todo-text: #6b5300;
  --shadow: 0 1px 2px rgba(0,0,0,.05), 0 4px 16px rgba(0,0,0,.05);
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101215;
    --surface: #181b20;
    --text: #e8eaed;
    --muted: #9aa3ad;
    --border: #2a2f37;
    --accent: #0dbd8b;
    --accent-soft: #10302a;
    --code-bg: #232831;
    --warn-bg: #2c1517;
    --warn-border: #ff6369;
    --todo-bg: #3d3300;
    --todo-text: #ffe27a;
    --shadow: 0 1px 2px rgba(0,0,0,.3), 0 4px 16px rgba(0,0,0,.25);
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 72px; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  -webkit-text-size-adjust: 100%;
}

.wrap { max-width: 860px; margin: 0 auto; padding: 0 16px; }

a { color: var(--accent); text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }

/* Header */
.hero { padding: 56px 0 32px; }
.eyebrow {
  margin: 0 0 8px;
  color: var(--accent);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: .04em;
}
h1 { font-size: clamp(28px, 5vw, 40px); line-height: 1.15; margin: 0 0 16px; text-wrap: balance; }
.lead { color: var(--muted); margin: 0; max-width: 68ch; }

/* Step nav */
.steps-nav {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.steps-nav ol {
  position: relative;
  display: flex;
  gap: 6px;
  list-style: none;
  margin: 0;
  padding: 10px 0;
  overflow-x: auto;
  scrollbar-width: none;
}
.steps-nav ol::-webkit-scrollbar { display: none; }
.steps-nav a {
  display: block;
  white-space: nowrap;
  padding: 6px 12px;
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
}
.steps-nav a:hover { color: var(--text); background: var(--code-bg); }
.steps-nav a.active { color: var(--accent); background: var(--accent-soft); }

/* Cards */
main { padding: 24px 16px 8px; }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 24px clamp(16px, 4vw, 32px);
  margin-bottom: 20px;
  box-shadow: var(--shadow);
}
.card > :last-child { margin-bottom: 0; }

h2 {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: clamp(20px, 3.4vw, 24px);
  line-height: 1.25;
  margin: 0 0 16px;
}
h3 { font-size: 17px; margin: 24px 0 8px; }
.num {
  flex: none;
  display: inline-grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 16px;
}

ul, ol { padding-left: 1.4em; }
li { margin: 6px 0; }
li::marker { color: var(--muted); }
.instructions > li { margin: 12px 0; padding-left: 4px; }

.lexicon { columns: 2 320px; column-gap: 32px; }
.lexicon li { break-inside: avoid; }
.note { color: var(--muted); font-size: 15px; }

/* Code + copy */
code, kbd {
  font: 0.88em/1.4 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 6px;
  overflow-wrap: anywhere;
}
kbd { border: 1px solid var(--border); border-bottom-width: 2px; }
code.copy { cursor: pointer; border: 1px dashed var(--accent); }
code.copy::after { content: " ⧉"; color: var(--accent); }
code.copy.copied::after { content: " ✓ copied"; }

.todo, code.todo {
  background: var(--todo-bg);
  color: var(--todo-text);
  padding: 2px 6px;
  border-radius: 6px;
  font-weight: 600;
}

/* Screenshots */
figure { margin: 12px 0 16px; }
figure img {
  display: block;
  max-width: min(100%, 640px);
  height: auto;
  border-radius: 10px;
  border: 1px solid var(--border);
  cursor: zoom-in;
}

/* Warning */
.warning {
  margin-top: 20px;
  padding: 16px 20px;
  background: var(--warn-bg);
  border-left: 5px solid var(--warn-border);
  border-radius: 8px;
}
.warning p { margin: 4px 0; }

/* Footer */
.footer { color: var(--muted); font-size: 14px; padding-bottom: 40px; text-align: center; }

/* Lightbox */
dialog {
  border: none;
  padding: 0;
  background: transparent;
  max-width: 96vw;
  max-height: 96vh;
}
dialog::backdrop { background: rgba(0,0,0,.82); }
dialog img { display: block; max-width: 96vw; max-height: 90vh; border-radius: 10px; }
dialog form { text-align: right; }
dialog .close {
  margin-bottom: 8px;
  background: rgba(255,255,255,.15);
  color: #fff;
  border: none;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  font-size: 16px;
  cursor: pointer;
}

@media (max-width: 520px) {
  body { font-size: 16px; }
  .hero { padding: 36px 0 24px; }
  main { padding-top: 16px; }
}