:root {
  --paper: #f4f1e9;
  --paper-deep: #ebe4d4;
  --ink: #111111;
  --muted: #4a463c;
  --rule: rgba(17, 17, 17, 0.18);
  --serif: "Songti SC", "STSong", "Songti SC Regular", Georgia, "Times New Roman", serif;
  --meta: Georgia, "Times New Roman", serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --measure: 38rem;
}

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

html {
  background: var(--paper);
  color: var(--ink);
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--serif);
  font-size: 1.05rem;
  line-height: 1.7;
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(255, 255, 255, 0.35), transparent 55%),
    var(--paper);
  color: var(--ink);
}

img { max-width: 100%; height: auto; display: block; }
a { color: var(--ink); text-underline-offset: 0.18em; }
a:hover { text-decoration-thickness: 2px; }
strong { font-weight: 600; }
code { font-family: var(--mono); font-size: 0.92em; }

.skip {
  position: absolute;
  left: 1rem;
  top: -3rem;
  background: var(--ink);
  color: var(--paper);
  padding: 0.4rem 0.8rem;
  z-index: 10;
}
.skip:focus { top: 0.6rem; }

:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
}

.mast {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  max-width: 1120px;
  margin: 0 auto;
  padding: 1.4rem 1.25rem 1.1rem;
  border-bottom: 1px solid var(--ink);
}

.wordmark {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  font-family: var(--meta);
  font-size: 1.15rem;
  letter-spacing: 0.08em;
}
.wordmark img { width: 28px; height: 28px; }

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1.15rem;
  font-family: var(--meta);
  font-size: 0.92rem;
  letter-spacing: 0.04em;
}
nav a { text-decoration: none; }
nav a:hover { text-decoration: underline; }

.hero,
.sheet,
.colophon {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 3rem 3.5rem;
  align-items: center;
  padding-top: 3.4rem;
  padding-bottom: 3.2rem;
  border-bottom: 1px solid var(--ink);
}
.hero-copy { min-width: 0; }

.kicker {
  margin: 0 0 0.85rem;
  font-family: var(--meta);
  font-size: 0.78rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--muted);
}

h1, h2, h3 { font-weight: 600; letter-spacing: 0.02em; line-height: 1.15; }
h1 { font-size: clamp(1.9rem, 8vw, 4.35rem); margin: 0 0 1.15rem; }
h2 { font-size: clamp(1.7rem, 3vw, 2.35rem); margin: 0; }
h3 { font-size: 1.2rem; margin: 0 0 0.45rem; }

.lede {
  max-width: var(--measure);
  margin: 0 0 1.5rem;
  font-size: 1.12rem;
  color: var(--ink);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.85rem 1.4rem;
  margin: 0 0 1rem;
}

.btn {
  display: inline-block;
  background: var(--ink);
  color: var(--paper);
  text-decoration: none;
  padding: 0.7rem 1.25rem;
  letter-spacing: 0.08em;
  font-family: var(--meta);
  font-size: 0.95rem;
}
.btn:hover { color: var(--paper); }

.text-btn {
  font-family: var(--meta);
  letter-spacing: 0.04em;
}

.fine, .note, .more {
  color: var(--muted);
  font-size: 0.95rem;
}
.fine { margin: 0; max-width: 28rem; }

.oasis { margin: 0; }
.oasis-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 18px;
  background: #1c1a16;
  border-radius: 18px 8px 8px 18px;
  padding: 14px 7px 14px 14px;
  max-width: 380px;
  margin-left: auto;
}
.oasis-screen {
  background: #f4efe4;
  border-radius: 3px;
  overflow: hidden;
  border: 1px solid #111;
  aspect-ratio: 1072 / 1448;
}
.oasis-screen img {
  width: 100%;
  height: 100%;
  max-width: none;
  object-fit: cover;
}
.oasis-keys {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 22px;
  padding: 48px 3px;
}
.oasis-keys span {
  display: block;
  height: 42px;
  background: #2f2c27;
  border-radius: 2px;
}
.oasis figcaption {
  margin-top: 0.7rem;
  text-align: right;
  font-family: var(--meta);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.sheet {
  padding-top: 3.1rem;
  padding-bottom: 3.1rem;
  border-bottom: 1px solid var(--rule);
}
.sheet-head { margin-bottom: 1.8rem; max-width: 36rem; }

.folio {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.5rem 2rem;
}
.folio article {
  padding-top: 1rem;
  border-top: 1px solid var(--ink);
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem 3rem;
}
.split ul {
  margin: 0;
  padding-left: 1.1rem;
}
.split li + li { margin-top: 0.35rem; }
.note { margin: 1.6rem 0 0; max-width: 46rem; }

.steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.6rem;
  counter-reset: step;
}
.steps li {
  counter-increment: step;
  padding-top: 1rem;
  border-top: 1px solid var(--rule);
}
.steps h3::before {
  content: counter(step, decimal-leading-zero) "  ";
  font-family: var(--meta);
  letter-spacing: 0.12em;
  color: var(--muted);
  font-size: 0.85em;
}

.cmd {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.6rem;
  align-items: start;
  margin-top: 0.7rem;
  background: var(--paper-deep);
  border: 1px solid var(--ink);
  padding: 0.7rem 0.75rem;
}
.cmd pre {
  margin: 0;
  min-width: 0;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 0.86rem;
  line-height: 1.55;
}
.cmd button {
  font-family: var(--meta);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  background: var(--ink);
  color: var(--paper);
  border: 0;
  padding: 0.4rem 0.7rem;
  cursor: pointer;
}
.cmd button[data-copied="1"] { background: transparent; color: var(--ink); border: 1px solid var(--ink); }

.more { margin: 1.8rem 0 0; }

.colophon {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.7rem 1.2rem;
  padding-top: 1.6rem;
  padding-bottom: 2.4rem;
  font-family: var(--meta);
  font-size: 0.88rem;
  letter-spacing: 0.04em;
  color: var(--muted);
}
.colophon p { margin: 0; }
.colophon img { width: 24px; height: 24px; }

@media (max-width: 860px) {
  .hero {
    grid-template-columns: 1fr;
    gap: 2.2rem;
    padding-top: 2.2rem;
  }
  .oasis-shell { margin-left: 0; }
  .folio, .split { grid-template-columns: 1fr; }
}

@media (max-width: 520px) {
  body { font-size: 1rem; }
  .mast, .hero, .sheet, .colophon { padding-left: 1rem; padding-right: 1rem; }
  h1 { font-size: clamp(1.85rem, 9vw, 2.5rem); }
  .cmd { grid-template-columns: 1fr; }
  .cmd button { justify-self: start; }
}

@media (prefers-reduced-motion: no-preference) {
  .rise { animation: rise 0.7s ease both; }
  .oasis-shell { animation: rest 7s ease-in-out infinite; }
  .hero-copy.rise { animation-delay: 0.04s; }
  .oasis.rise { animation-delay: 0.14s; }
}

@keyframes rise {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: none; }
}
@keyframes rest {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-5px); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .rise, .oasis-shell { animation: none; }
}