:root {
  --ink: #18212c;
  --ink-soft: #3d4a5c;
  --muted: #66758a;
  --accent: #1f6b5c;
  --accent-hover: #155248;
  --line: rgba(24, 33, 44, 0.12);
  --surface: rgba(252, 253, 255, 0.72);
  --bg-top: #dce6ef;
  --bg-mid: #e8edf2;
  --bg-bottom: #f4f6f8;
  --serif: "Fraunces", "Iowan Old Style", "Palatino Linotype", Palatino, serif;
  --sans: "Public Sans", "Segoe UI", sans-serif;
  --radius: 2px;
  --measure: 40rem;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.7;
  background: var(--bg-bottom);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.atmosphere {
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(ellipse 90% 55% at 12% -10%, rgba(120, 168, 196, 0.45), transparent 55%),
    radial-gradient(ellipse 70% 50% at 88% 8%, rgba(90, 150, 138, 0.22), transparent 50%),
    linear-gradient(180deg, var(--bg-top) 0%, var(--bg-mid) 38%, var(--bg-bottom) 100%);
}

.grain {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: 0.35;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.55'/%3E%3C/svg%3E");
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  z-index: 20;
  padding: 0.55rem 0.9rem;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
  border-radius: var(--radius);
  transition: top 0.2s var(--ease);
}

.skip-link:focus {
  top: 1rem;
}

.shell {
  width: min(1120px, calc(100% - 2.5rem));
  margin: 0 auto;
  padding: 3.5rem 0 4.5rem;
}

.hero {
  margin-bottom: 3.25rem;
  max-width: 36rem;
}

.brand {
  margin: 0 0 0.85rem;
  font-family: var(--serif);
  font-size: clamp(2.6rem, 6vw, 3.75rem);
  font-weight: 600;
  font-variation-settings: "SOFT" 40, "WONK" 0.4;
  letter-spacing: -0.03em;
  line-height: 1.05;
  color: var(--ink);
}

.hero h1 {
  margin: 0 0 0.65rem;
  font-family: var(--serif);
  font-size: clamp(1.55rem, 3.2vw, 2rem);
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--ink-soft);
}

.updated {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
  font-weight: 500;
}

.layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
}

@media (min-width: 920px) {
  .layout {
    grid-template-columns: 13.5rem minmax(0, 1fr);
    gap: 3.75rem;
    align-items: start;
  }
}

.toc {
  position: relative;
}

@media (min-width: 920px) {
  .toc {
    position: sticky;
    top: 1.75rem;
  }
}

.toc-label {
  margin: 0 0 0.75rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.toc ol {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  border-left: 1px solid var(--line);
  padding-left: 0.95rem;
}

.toc a {
  display: inline-block;
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 0.9rem;
  line-height: 1.35;
  transition: color 0.2s var(--ease), transform 0.2s var(--ease);
}

.toc a:hover,
.toc a:focus-visible {
  color: var(--accent);
}

.toc a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

@media (max-width: 919px) {
  .toc {
    padding: 1rem 1.1rem;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 10px;
    backdrop-filter: blur(10px);
  }

  .toc ol {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.45rem 1rem;
    border-left: none;
    padding-left: 0;
  }
}

@media (max-width: 560px) {
  .toc ol {
    grid-template-columns: 1fr;
  }
}

main {
  min-width: 0;
}

section {
  max-width: var(--measure);
  padding: 1.65rem 0 1.85rem;
  border-top: 1px solid var(--line);
}

section:first-child {
  border-top: none;
  padding-top: 0;
}

.lead-section {
  padding-bottom: 2.25rem;
}

h2 {
  margin: 0 0 0.9rem;
  font-family: var(--serif);
  font-size: clamp(1.35rem, 2.4vw, 1.65rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.25;
}

h3 {
  margin: 1.35rem 0 0.55rem;
  font-family: var(--serif);
  font-size: 1.12rem;
  font-weight: 600;
  color: var(--ink-soft);
}

p,
ul {
  margin: 0 0 1rem;
}

p:last-child,
ul:last-child {
  margin-bottom: 0;
}

.lead {
  font-size: clamp(1.12rem, 2vw, 1.28rem);
  line-height: 1.65;
  color: var(--ink);
}

.emphasis {
  margin-top: 1.15rem;
  font-family: var(--serif);
  font-size: 1.15rem;
  font-weight: 600;
  font-style: italic;
  color: var(--ink);
}

ul {
  padding-left: 1.15rem;
}

li {
  margin-bottom: 0.55rem;
  padding-left: 0.2rem;
}

li:last-child {
  margin-bottom: 0;
}

.plain-list {
  list-style: none;
  padding-left: 0;
}

.plain-list li {
  position: relative;
  padding-left: 1.15rem;
}

.plain-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 0.4rem;
  height: 0.4rem;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.7;
}

a {
  color: var(--accent);
  text-underline-offset: 0.18em;
  text-decoration-thickness: 1px;
  transition: color 0.2s var(--ease);
}

a:hover {
  color: var(--accent-hover);
}

a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

.site-footer {
  margin-top: 3.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.92rem;
}

.site-footer p {
  margin: 0;
}

.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition:
    opacity 0.7s var(--ease),
    transform 0.7s var(--ease);
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

.hero.reveal {
  transition-delay: 0.05s;
}

main section.reveal:nth-of-type(1) {
  transition-delay: 0.08s;
}

@media (max-width: 640px) {
  .shell {
    width: min(100% - 1.5rem, 1120px);
    padding-top: 2.5rem;
  }

  .brand {
    font-size: 2.45rem;
  }
}