/* ==========================================================================
   Anthropic-style base + components
   Zero shadows. Surface contrast is the only depth signal.
   ========================================================================== */

/* ---- Reset ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  font-weight: var(--fw-regular);
  font-size: var(--text-body-sm);
  line-height: var(--leading-body-sm);
  letter-spacing: var(--tracking-body-sm);
  color: var(--color-slate-dark);
  background-color: var(--surface-page-base);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: none; cursor: pointer; }
ul, ol { list-style: none; }
::selection { background: var(--color-clay); color: var(--color-ivory-light); }

/* ---- Layout primitives ---- */
.container {
  width: 100%;
  max-width: var(--page-max-width);
  margin-inline: auto;
  padding-inline: var(--spacing-32);
}
.section { padding-block: var(--section-gap); }
.section--tight { padding-block: var(--spacing-48); }

/* ---- Mono labels (metadata) ---- */
.mono {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: var(--fw-regular);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-cloud-dark);
}
.mono--dark { color: var(--color-ivory-dark); }

/* ---- Eyebrow / kicker ---- */
.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-clay);
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-8);
}
.eyebrow::before {
  content: "";
  width: 18px;
  height: 1px;
  background: currentColor;
  display: inline-block;
}

/* ==========================================================================
   Top Navigation
   ========================================================================== */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(240, 238, 230, 0.82);
  backdrop-filter: saturate(160%) blur(10px);
  -webkit-backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.nav.is-scrolled { border-bottom-color: var(--color-ivory-dark); }
.nav__inner {
  height: 68px;
  max-width: var(--page-max-width);
  margin-inline: auto;
  padding-inline: var(--spacing-32);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-32);
}
.nav__brand {
  font-family: var(--font-sans);
  font-weight: var(--fw-bold);
  font-size: 16px;
  letter-spacing: -0.01em;
  color: var(--color-slate-dark);
  display: flex;
  align-items: center;
  gap: 8px;
}
.nav__brand .mark {
  width: 22px; height: 22px;
  display: grid; place-items: center;
  background: var(--color-slate-dark);
  color: var(--color-ivory-light);
  border-radius: 4px;
  font-size: 13px;
  font-weight: var(--fw-bold);
}
.nav__links {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav__link {
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: var(--fw-regular);
  color: var(--color-slate-dark);
  padding: 10px 14px;
  position: relative;
  transition: color var(--dur) var(--ease);
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 14px; right: 14px; bottom: 6px;
  height: 1.5px;
  background: var(--color-slate-dark);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur) var(--ease);
}
.nav__link:hover::after { transform: scaleX(1); }
.nav__cta { display: flex; align-items: center; gap: var(--spacing-12); }
.nav__menu-btn { display: none; }

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: var(--fw-medium);
  padding: 12px 22px;
  border: 1px solid var(--color-slate-dark);
  border-radius: 0;
  color: var(--color-slate-dark);
  background: transparent;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
  cursor: pointer;
}
.btn:hover { background: var(--color-slate-dark); color: var(--color-ivory-light); }
.btn--primary {
  background: var(--color-ivory-light);
  border-radius: 0 0 8px 8px; /* asymmetric signature */
  padding-block: 12px;
}
.btn--primary:hover { background: var(--color-slate-dark); color: var(--color-ivory-light); }
.btn--solid {
  background: var(--color-slate-dark);
  color: var(--color-ivory-light);
}
.btn--solid:hover { background: var(--color-clay); border-color: var(--color-clay); }
.btn--on-dark {
  background: var(--color-ivory-light);
  color: var(--color-slate-dark);
  border-color: var(--color-ivory-light);
}
.btn--on-dark:hover { background: var(--color-clay); color: var(--color-ivory-light); border-color: var(--color-clay); }
.btn--ghost { border-color: var(--color-cloud-medium); color: var(--color-cloud-dark); cursor: default; }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  padding-top: clamp(56px, 9vw, 96px);
  padding-bottom: clamp(40px, 6vw, 64px);
}
.hero__grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: var(--spacing-48);
  align-items: start;
}
.hero__title {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(44px, 7vw, 91px);
  line-height: 1.02;
  letter-spacing: -0.025em;
  color: var(--color-slate-dark);
}
.hero__title .emph {
  text-decoration: underline;
  text-decoration-thickness: 4px;
  text-underline-offset: 8px;
  text-decoration-color: var(--color-clay);
}
.hero__title .zh {
  font-family: var(--font-zh);
  font-weight: 400;
  font-style: normal;
  font-size: 0.5em;
  line-height: 1.5;
  letter-spacing: 0.02em;
  display: inline-block;
  vertical-align: baseline;
  color: var(--color-slate-light);
}
.zh-line {
  font-family: var(--font-zh);
  font-weight: 400;
  font-style: normal;
  font-size: clamp(18px, 2.4vw, 26px);
  line-height: 1.45;
  letter-spacing: 0.04em;
  color: var(--color-slate-light);
  margin-top: 14px;
  display: block;
}
.hero__lede {
  margin-top: var(--spacing-32);
  font-size: 18px;
  line-height: 1.5;
  color: var(--color-slate-light);
  max-width: 30ch;
}
.hero__aside {
  padding-top: 12px;
}
.hero__meta {
  display: grid;
  gap: 18px;
  border-top: 1px solid var(--color-cloud-light);
  padding-top: 24px;
}
.hero__meta-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
}
.hero__meta-row .val {
  font-family: var(--font-sans);
  font-size: 15px;
  color: var(--color-slate-dark);
  font-weight: var(--fw-medium);
  text-align: right;
}
.hero__intro {
  margin-top: 24px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--color-slate-light);
}

/* ---- Inline text link (arrow) ---- */
.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-sans);
  font-size: 15px;
  color: var(--color-slate-dark);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease), gap var(--dur) var(--ease);
}
.link-arrow .arrow { transition: transform var(--dur) var(--ease); }
.link-arrow:hover { border-bottom-color: var(--color-slate-dark); gap: 10px; }
.link-arrow:hover .arrow { transform: translateX(2px); }
.link-arrow--on-dark { color: var(--color-ivory-light); }
.link-arrow--on-dark:hover { border-bottom-color: var(--color-ivory-light); }

/* ==========================================================================
   Section heading
   ========================================================================== */
.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: var(--spacing-32);
  border-top: 1px solid var(--color-slate-dark);
  padding-top: 20px;
}
.section-head__title {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.1;
  letter-spacing: -0.015em;
}
.section-head__count {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-cloud-dark);
  letter-spacing: 0.08em;
  white-space: nowrap;
  padding-bottom: 6px;
}

/* ==========================================================================
   Dark Editorial Feature Card
   ========================================================================== */
.feature {
  background: var(--surface-feature-dark);
  color: var(--color-ivory-light);
  border-radius: var(--radius-featuredcards);
  padding: clamp(28px, 4vw, 48px);
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: clamp(24px, 4vw, 48px);
  align-items: center;
  overflow: hidden;
  position: relative;
}
.feature__eyebrow { color: var(--color-clay); }
.feature__title {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(34px, 5vw, 64px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--color-ivory-light);
  margin-top: 18px;
}
.feature__title .zh {
  font-family: var(--font-zh);
  font-style: normal;
  font-size: 0.46em;
  line-height: 1.45;
  letter-spacing: 0.04em;
  display: inline-block;
  vertical-align: baseline;
  color: var(--color-ivory-dark);
}
.feature__sub {
  margin-top: 20px;
  font-size: 18px;
  line-height: 1.5;
  color: var(--color-ivory-dark);
  max-width: 42ch;
}
.feature__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 22px;
  margin-top: 26px;
}
.feature__cta { margin-top: 30px; }
.feature__visual {
  aspect-ratio: 1 / 1;
  border-radius: var(--radius-2xl);
  overflow: hidden;
  position: relative;
  background: #0c0c0b;
}
.feature__visual svg { width: 100%; height: 100%; }

/* ==========================================================================
   Project grid (release cards)
   ========================================================================== */
.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-16);
}
.card {
  background: var(--surface-nav-elevated-light);
  border-radius: var(--radius-cards);
  padding: var(--card-padding);
  display: flex;
  flex-direction: column;
  gap: 14px;
  min-height: 280px;
  position: relative;
  transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
  border: 1px solid transparent;
}
.card:hover { background: var(--surface-oat-card); }
.card--oat { background: var(--surface-oat-card); }
.card--oat:hover { background: var(--color-ivory-dark); }
.card__top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}
.card__lang {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 4px 8px;
  border: 1px solid var(--color-cloud-light);
  border-radius: 0;
  color: var(--color-slate-medium);
}
.card__stars {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-cloud-dark);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.card__title {
  font-family: var(--font-sans);
  font-weight: var(--fw-semibold);
  font-size: 20px;
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--color-slate-dark);
  margin-top: auto;
}
.card__desc {
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-slate-light);
}
.card__topics {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 4px;
}
.topic {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-cloud-dark);
  letter-spacing: 0.02em;
}
.card__footer {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--color-cloud-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

/* ==========================================================================
   Stats strip
   ========================================================================== */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-16);
  border-top: 1px solid var(--color-slate-dark);
  border-bottom: 1px solid var(--color-cloud-light);
  padding-block: 32px;
}
.stat__num {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(40px, 5vw, 64px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--color-slate-dark);
}
.stat__label {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-cloud-dark);
}

/* ==========================================================================
   Writing / notes
   ========================================================================== */
.notes { display: grid; grid-template-columns: repeat(2, 1fr); gap: var(--spacing-16); }
.note {
  border-top: 1px solid var(--color-slate-dark);
  padding-top: 20px;
  display: block;
  transition: opacity var(--dur) var(--ease);
}
.note:hover { opacity: 0.65; }
.note__date { font-family: var(--font-mono); font-size: 12px; color: var(--color-cloud-dark); letter-spacing: 0.06em; }
.note__title {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: 24px;
  line-height: 1.2;
  margin-top: 10px;
  color: var(--color-slate-dark);
}
.note__excerpt { margin-top: 10px; font-size: 15px; color: var(--color-slate-light); line-height: 1.55; }

/* ==========================================================================
   Now / about band
   ========================================================================== */
.band {
  background: var(--surface-nav-elevated-light);
  border-radius: var(--radius-panels);
  padding: clamp(28px, 4vw, 48px);
}
.band__grid {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: clamp(24px, 4vw, 48px);
  align-items: start;
}
.band__list { display: grid; gap: 16px; }
.band__item {
  display: grid;
  grid-template-columns: 24px 1fr;
  gap: 14px;
  align-items: start;
}
.band__item .dot {
  width: 8px; height: 8px;
  background: var(--color-clay);
  border-radius: 50%;
  margin-top: 8px;
}
.band__item h4 { font-family: var(--font-sans); font-weight: var(--fw-semibold); font-size: 16px; }
.band__item p { font-size: 14px; color: var(--color-slate-light); line-height: 1.5; margin-top: 2px; }

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
  border-top: 1px solid var(--color-slate-dark);
  padding-block: 56px 40px;
  margin-top: var(--section-gap);
}
.footer__top {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 32px;
}
.footer__mark {
  font-family: var(--font-serif);
  font-size: clamp(40px, 8vw, 91px);
  line-height: 1;
  letter-spacing: -0.03em;
}
.footer__mark .emph {
  text-decoration: underline;
  text-decoration-color: var(--color-clay);
  text-decoration-thickness: 5px;
  text-underline-offset: 6px;
}
.footer__col h5 {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-cloud-dark);
  margin-bottom: 14px;
}
.footer__col a {
  display: block;
  font-size: 15px;
  padding: 5px 0;
  border-bottom: 1px solid transparent;
  width: fit-content;
  transition: border-color var(--dur) var(--ease);
}
.footer__col a:hover { border-bottom-color: var(--color-slate-dark); }
.footer__bottom {
  margin-top: 48px;
  padding-top: 20px;
  border-top: 1px solid var(--color-cloud-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-cloud-dark);
  letter-spacing: 0.04em;
}

/* ==========================================================================
   Reveal animation
   ========================================================================== */
.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 700ms var(--ease), transform 700ms var(--ease);
}
.reveal.is-in { opacity: 1; transform: none; }

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 980px) {
  .hero__grid { grid-template-columns: 1fr; gap: 32px; }
  .feature { grid-template-columns: 1fr; }
  .feature__visual { order: -1; max-width: 360px; }
  .grid { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); gap: 28px; }
  .band__grid { grid-template-columns: 1fr; }
  .footer__top { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .container { padding-inline: 20px; }
  .nav__inner { padding-inline: 20px; }
  .nav__links { display: none; }
  .nav__menu-btn {
    display: inline-flex; align-items: center; gap: 6px;
    font-size: 15px; color: var(--color-slate-dark);
  }
  .grid { grid-template-columns: 1fr; }
  .notes { grid-template-columns: 1fr; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .footer__top { grid-template-columns: 1fr; }
  .footer__bottom { flex-direction: column; align-items: flex-start; }
  .section-head { flex-direction: column; align-items: flex-start; }
}