:root {
  --fg: #1a1a1a;
  --muted: #555;
  --bg: #fafafa;
  --card: #ffffff;
  --line: #e5e5e5;
  --accent: #6b5800;
  --accent-bg: #fff3cd;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  color: var(--fg);
  background: var(--bg);
  line-height: 1.5;
}

* { box-sizing: border-box; }
body { margin: 0; }
a { color: inherit; }

.container { max-width: 1100px; margin: 0 auto; padding: 2rem 1.25rem; }

.site-header {
  border-bottom: 1px solid var(--line);
  background: var(--card);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
}
.brand { font-weight: 700; font-size: 1.05rem; text-decoration: none; }
.tag {
  display: inline-block;
  background: var(--accent-bg);
  color: var(--accent);
  padding: .15rem .55rem;
  border-radius: .25rem;
  font-size: .75rem;
  font-weight: 600;
  letter-spacing: .04em;
  text-transform: uppercase;
}

h1 { font-size: 2rem; line-height: 1.15; margin: 0 0 1rem; }
h2 { font-size: 1.2rem; margin: 2rem 0 .75rem; }
.lead { font-size: 1.1rem; color: var(--muted); margin: 0 0 2rem; max-width: 60ch; }

.design-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
  margin: 2rem 0;
}
.design-card {
  display: block;
  text-decoration: none;
  color: inherit;
  border: 1px solid var(--line);
  border-radius: .5rem;
  padding: 1.25rem;
  background: var(--card);
  transition: border-color .15s ease, transform .15s ease;
}
.design-card:hover { border-color: var(--fg); transform: translateY(-2px); }
.design-card .num {
  font-size: .75rem;
  font-weight: 700;
  color: #888;
  letter-spacing: .1em;
}
.design-card h3 { margin: .35rem 0 .5rem; font-size: 1.1rem; }
.design-card p { margin: 0; color: var(--muted); font-size: .95rem; }

.back-link { display: inline-block; margin-bottom: 1rem; color: var(--muted); text-decoration: none; }
.back-link:hover { color: var(--fg); }

.mock {
  border: 1px dashed #c0c0c0;
  border-radius: .5rem;
  padding: 1.25rem;
  background: var(--card);
  margin: 1rem 0 2rem;
}
.mock h2 { margin-top: 0; }
.mock-row { display: flex; gap: 1rem; flex-wrap: wrap; }
.mock-col {
  flex: 1 1 220px;
  padding: 1rem;
  background: #f5f5f5;
  border-radius: .35rem;
}
.mock-col h3 { margin: 0 0 .35rem; font-size: 1rem; }
.mock-list { padding-left: 1.25rem; margin: .25rem 0 0; }
.mock-list li { margin: .15rem 0; }

.compare {
  width: 100%;
  border-collapse: collapse;
  margin-top: .5rem;
  background: var(--card);
}
.compare th,
.compare td {
  padding: .55rem .75rem;
  text-align: left;
  border-bottom: 1px solid var(--line);
  font-size: .95rem;
}
.compare thead { background: #f5f5f5; }

.chat { max-width: 640px; }
.bubble {
  padding: .65rem 1rem;
  border-radius: 1rem;
  margin: .5rem 0;
  display: block;
  width: fit-content;
  max-width: 85%;
}
.bubble.user { background: var(--fg); color: var(--card); margin-left: auto; }
.bubble.bot { background: #f0f0f0; }

.field {
  display: block;
  margin: .5rem 0;
  font-size: .9rem;
  color: var(--muted);
}
.field input,
.field select {
  width: 100%;
  padding: .5rem .65rem;
  border: 1px solid var(--line);
  border-radius: .35rem;
  font: inherit;
  background: var(--card);
}

.note {
  font-size: .9rem;
  color: var(--muted);
  margin: 1rem 0 0;
}