:root {
  --bg-a: #f2e6d0;
  --bg-b: #d9e8e2;
  --ink: #1f2929;
  --muted: #4b5959;
  --card: rgba(255, 255, 255, 0.92);
  --line: rgba(31, 41, 41, 0.16);
  --brand: #ab4d2e;
  --brand-deep: #7f3117;
  --focus: #0f6f6a;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: "Avenir Next", "Gill Sans", "Trebuchet MS", sans-serif;
  background:
    radial-gradient(circle at 90% 5%, rgba(171, 77, 46, 0.16), transparent 34%),
    radial-gradient(circle at 10% 95%, rgba(15, 111, 106, 0.14), transparent 28%),
    linear-gradient(150deg, var(--bg-a), var(--bg-b));
  min-height: 100dvh;
}

.shell {
  width: min(1100px, 100% - 2rem);
  margin: 1.25rem auto 2.5rem;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: 0 18px 34px rgba(31, 41, 41, 0.12);
  overflow: hidden;
}

.topbar {
  padding: 1.1rem 1.3rem;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.95), rgba(255, 255, 255, 0.7));
}

.kicker {
  display: inline-block;
  margin-bottom: 0.4rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 0.72rem;
  color: var(--brand);
  font-weight: 700;
}

h1 {
  margin: 0;
  font-family: "Bodoni MT", "Didot", serif;
  font-size: clamp(1.6rem, 3.2vw, 2.5rem);
  letter-spacing: 0.02em;
}

.subtitle {
  margin: 0.35rem 0 0;
  color: var(--muted);
  font-size: 0.98rem;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding: 0.95rem 1.3rem;
  border-bottom: 1px solid var(--line);
  background: rgba(247, 248, 246, 0.85);
}

.nav a {
  text-decoration: none;
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.42rem 0.8rem;
  font-size: 0.9rem;
  transition: 0.2s ease;
}

.nav a:hover,
.nav a:focus-visible {
  border-color: var(--focus);
  color: var(--focus);
  outline: none;
}

.nav a.active {
  background: var(--brand);
  color: #fff;
  border-color: var(--brand);
}

.content {
  padding: clamp(1rem, 2.4vw, 2rem);
}

.panel {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1rem;
  background: #fff;
  margin-bottom: 1rem;
}

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

h2 {
  margin: 0 0 0.6rem;
  font-size: clamp(1.15rem, 2.1vw, 1.4rem);
}

h3 {
  margin: 0.9rem 0 0.45rem;
  font-size: 1.02rem;
}

p {
  margin: 0 0 0.7rem;
  line-height: 1.65;
}

ul,
ol {
  margin: 0.2rem 0 0.9rem 1.35rem;
  padding: 0;
}

li {
  margin: 0.28rem 0;
  line-height: 1.55;
}

code {
  font-family: "SFMono-Regular", Menlo, Consolas, monospace;
  background: rgba(31, 41, 41, 0.07);
  padding: 0.1rem 0.28rem;
  border-radius: 6px;
}

pre {
  overflow-x: auto;
  padding: 0.82rem;
  margin: 0.45rem 0 1rem;
  border-radius: 10px;
  background: #1f2929;
  color: #edf3f3;
  font-family: "SFMono-Regular", Menlo, Consolas, monospace;
  font-size: 0.84rem;
  line-height: 1.45;
}

.code-block {
  position: relative;
  margin: 0.45rem 0 1rem;
}

.code-block pre {
  margin: 0;
  padding-top: 2.5rem;
}

.copy-btn {
  position: absolute;
  top: 0.55rem;
  right: 0.55rem;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  border: 1px solid rgba(237, 243, 243, 0.4);
  background: rgba(12, 20, 20, 0.68);
  color: #edf3f3;
  border-radius: 999px;
  font-size: 0.72rem;
  padding: 0.2rem 0.48rem;
  cursor: pointer;
}

.copy-btn svg {
  width: 0.88rem;
  height: 0.88rem;
  fill: currentColor;
}

.copy-btn:hover,
.copy-btn:focus-visible {
  border-color: rgba(237, 243, 243, 0.8);
  outline: none;
}

.copy-btn.copied {
  border-color: rgba(84, 221, 173, 0.9);
  color: #54ddad;
}

.note {
  padding: 0.75rem 0.85rem;
  border-left: 4px solid var(--brand);
  background: rgba(171, 77, 46, 0.08);
  border-radius: 0 8px 8px 0;
}

.footer {
  border-top: 1px solid var(--line);
  padding: 0.85rem 1.3rem 1rem;
  color: var(--muted);
  font-size: 0.86rem;
}

@media (max-width: 740px) {
  .shell {
    width: min(1100px, 100% - 1rem);
  }

  .nav {
    gap: 0.35rem;
    padding: 0.75rem;
  }

  .nav a {
    font-size: 0.84rem;
    padding: 0.4rem 0.72rem;
  }
}