/* ------------------------------------------------------------------
   William Huang — Portfolio
   Dark editorial system. No dependencies, no build step.
   ------------------------------------------------------------------ */

/* 1. Tokens --------------------------------------------------------- */

:root {
  --bg: #0f0e0c;
  --bg-soft: #16140f;
  --ink: #eae6dc;
  --ink-2: #a09c8f;
  --ink-3: #676358;
  --line: rgba(234, 230, 220, 0.16);
  --line-soft: rgba(234, 230, 220, 0.08);
  --accent: #e08544;
  --accent-soft: rgba(224, 133, 68, 0.1);

  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  --font-serif: "Instrument Serif", Georgia, "Times New Roman", serif;
  --font-mono: "JetBrains Mono", "SF Mono", Menlo, Consolas, monospace;

  --shell: 1120px;
  --gutter: clamp(1.25rem, 5vw, 3rem);

  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --dur: 0.7s;
}

/* 2. Reset & base --------------------------------------------------- */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  background: var(--bg);
}

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  font-weight: 400;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Film grain over everything — the texture that keeps flat panels alive */
body::after {
  content: "";
  position: fixed;
  inset: -50%;
  z-index: 2000;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='300' height='300' filter='url(%23n)'/%3E%3C/svg%3E");
  opacity: 0.05;
}

::selection {
  background: var(--accent);
  color: var(--bg);
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

ul,
ol {
  list-style: none;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

em {
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 400;
}

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--bg-soft);
  padding: 0.1em 0.35em;
  border-radius: 4px;
}

strong {
  font-weight: 600;
}

.js body {
  animation: page-in 0.5s var(--ease-out) both;
}

@keyframes page-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  z-index: 3000;
  background: var(--ink);
  color: var(--bg);
  padding: 0.5rem 1rem;
  border-radius: 4px;
  font-size: 0.85rem;
}

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

/* 3. Typography helpers --------------------------------------------- */

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-2);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.eyebrow::before {
  content: "";
  width: 2rem;
  height: 1px;
  background: var(--accent);
  flex: none;
}

.display {
  font-size: clamp(2.6rem, 7.5vw, 5.25rem);
  line-height: 1.04;
  font-weight: 500;
  letter-spacing: -0.035em;
  text-wrap: balance;
}

.display em {
  letter-spacing: -0.01em;
  margin-right: 0.03em;
  color: var(--accent);
}

.lede {
  font-size: clamp(1.05rem, 1.8vw, 1.25rem);
  line-height: 1.6;
  color: var(--ink-2);
  max-width: 34em;
  text-wrap: pretty;
}

.prose {
  color: var(--ink-2);
  max-width: 40em;
  text-wrap: pretty;
}

.prose + .prose {
  margin-top: 1em;
}

.prose strong {
  color: var(--ink);
}

.u-link,
.inline-link {
  color: var(--ink);
  font-weight: 500;
  background-image: linear-gradient(var(--accent), var(--accent));
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 100% 1px;
  padding-bottom: 2px;
  transition: color 0.25s ease, background-size 0.35s var(--ease-out);
}

.u-link:hover,
.inline-link:hover {
  color: var(--accent);
  background-size: 0% 1px;
  background-position: 100% 100%;
}

/* 4. Reveal-on-scroll ----------------------------------------------- */

.js [data-reveal] {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity var(--dur) var(--ease-out), transform var(--dur) var(--ease-out);
  transition-delay: calc(var(--d, 0) * 90ms);
}

.js [data-reveal].is-in {
  opacity: 1;
  transform: none;
}

.line {
  display: block;
  overflow: hidden;
  padding-bottom: 0.08em;
  margin-bottom: -0.08em;
}

.line-inner {
  display: block;
}

.js .line-inner {
  transform: translateY(115%);
  animation: line-up 0.9s var(--ease-out) forwards;
  animation-delay: calc(0.12s + var(--l, 0) * 0.11s);
}

@keyframes line-up {
  to {
    transform: translateY(0);
  }
}

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

  .js body {
    animation: none;
  }

  .js [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .js .line-inner {
    transform: none;
    animation: none;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001s !important;
    transition-duration: 0.001s !important;
  }
}

/* 5. Header --------------------------------------------------------- */

.site-head {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 80%, transparent);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: transform 0.45s var(--ease-out), border-color 0.3s ease;
}

.site-head.is-scrolled {
  border-bottom-color: var(--line-soft);
}

.site-head.is-hidden {
  transform: translateY(-100%);
}

.head-inner {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
  height: 4.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: -0.01em;
}

.brand-role {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  color: var(--ink-3);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav-link {
  position: relative;
  font-size: 0.88rem;
  font-weight: 450;
  color: var(--ink-2);
  transition: color 0.25s ease;
  padding: 0.25rem 0;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: var(--ink);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.35s var(--ease-out);
}

.nav-link:hover {
  color: var(--ink);
}

.nav-link:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-link.is-active {
  color: var(--ink);
}

.nav-link.is-active::after {
  transform: scaleX(1);
  background: var(--accent);
}

.nav-cta {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.45rem 1rem;
  transition: border-color 0.25s ease, background 0.25s ease, color 0.25s ease;
}

.nav-cta::after {
  content: none;
}

.nav-cta:hover {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--bg);
}

.nav-toggle {
  display: none;
  z-index: 120;
  width: 2.5rem;
  height: 2.5rem;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

.nav-toggle span {
  display: block;
  width: 1.35rem;
  height: 1.5px;
  background: var(--ink);
  transition: transform 0.35s var(--ease-out), opacity 0.2s ease;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(3.75px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  transform: translateY(-3.75px) rotate(-45deg);
}

@media (max-width: 760px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: fixed;
    inset: 0;
    z-index: 110;
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    gap: 0.5rem;
    padding: var(--gutter);
    background: var(--bg);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.35s ease, visibility 0.35s ease;
  }

  .site-nav.is-open {
    opacity: 1;
    visibility: visible;
  }

  .site-nav .nav-link {
    font-size: clamp(1.9rem, 8vw, 2.6rem);
    font-weight: 500;
    letter-spacing: -0.02em;
    color: var(--ink);
    opacity: 0;
    transform: translateY(18px);
    transition: opacity 0.4s var(--ease-out), transform 0.4s var(--ease-out);
  }

  .site-nav.is-open .nav-link {
    opacity: 1;
    transform: none;
  }

  .site-nav.is-open .nav-link:nth-child(1) { transition-delay: 0.05s; }
  .site-nav.is-open .nav-link:nth-child(2) { transition-delay: 0.1s; }
  .site-nav.is-open .nav-link:nth-child(3) { transition-delay: 0.15s; }
  .site-nav.is-open .nav-link:nth-child(4) { transition-delay: 0.2s; }
  .site-nav.is-open .nav-link:nth-child(5) { transition-delay: 0.25s; }
  .site-nav.is-open .nav-link:nth-child(6) { transition-delay: 0.3s; }

  .site-nav .nav-link::after {
    height: 2px;
  }

  .site-nav .nav-cta {
    margin-top: 1.5rem;
    font-size: 0.85rem;
    padding: 0.7rem 1.5rem;
  }
}

/* 6. Shell & sections ----------------------------------------------- */

.shell {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
  flex: 1;
}

.hero {
  position: relative;
  padding-top: clamp(8rem, 20vh, 12rem);
  padding-bottom: clamp(4rem, 9vh, 7rem);
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

/* Warm glow bleeding in from the top corner */
.hero::before {
  content: "";
  position: absolute;
  top: -20%;
  left: -15%;
  width: 60vw;
  height: 60vw;
  max-width: 780px;
  max-height: 780px;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    rgba(224, 133, 68, 0.13),
    rgba(224, 133, 68, 0.04) 45%,
    transparent 68%
  );
  pointer-events: none;
  z-index: -1;
}

.hero .lede {
  max-width: 30em;
}

.block {
  border-top: 1px solid var(--line);
  padding: clamp(3.5rem, 8vh, 5.5rem) 0;
}

.block-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: clamp(2rem, 5vh, 3rem);
}

.block-title {
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
}

.block-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent);
  letter-spacing: 0.06em;
}

.block-more {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-2);
  transition: color 0.25s ease;
  white-space: nowrap;
}

.block-more::after {
  content: "→";
  display: inline-block;
  margin-left: 0.4em;
  transition: transform 0.3s var(--ease-out);
}

.block-more:hover {
  color: var(--accent);
}

.block-more:hover::after {
  transform: translateX(4px);
}

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.45rem 1rem;
  background: color-mix(in srgb, var(--bg-soft) 70%, transparent);
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  position: relative;
}

.status-dot::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: var(--accent);
  animation: pulse 2.4s ease-out infinite;
}

@keyframes pulse {
  0% {
    transform: scale(1);
    opacity: 0.7;
  }
  70%,
  100% {
    transform: scale(3);
    opacity: 0;
  }
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem;
  border-top: 1px solid var(--line-soft);
  padding-top: 1.5rem;
}

.hero-meta li {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.meta-k {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.meta-v {
  font-size: 0.9rem;
  font-weight: 500;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.9rem;
}

.cta {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: 999px;
  padding: 0.8rem 1.6rem;
  border: 1px solid var(--line);
  overflow: hidden;
  transition: color 0.3s ease, border-color 0.3s ease, transform 0.3s var(--ease-out);
}

.cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--ink);
  border-radius: inherit;
  transform: scaleY(0);
  transform-origin: bottom;
  transition: transform 0.35s var(--ease-out);
  z-index: -1;
}

.cta:hover {
  color: var(--bg);
  border-color: var(--ink);
  transform: translateY(-2px);
}

.cta:hover::before {
  transform: scaleY(1);
}

.cta.is-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--bg);
}

.cta.is-primary::before {
  background: var(--ink);
}

.cta.is-primary:hover {
  border-color: var(--ink);
}

.quiet-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--ink-2);
  background-image: linear-gradient(var(--ink-2), var(--ink-2));
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 100% 1px;
  padding-bottom: 2px;
  transition: color 0.25s ease, background-size 0.35s var(--ease-out);
}

.quiet-link:hover {
  color: var(--accent);
  background-size: 0% 1px;
  background-position: 100% 100%;
}

/* 7. Work list ------------------------------------------------------ */

.work-list {
  display: flex;
  flex-direction: column;
}

.work-row {
  border-top: 1px solid var(--line-soft);
}

.work-row:first-child {
  border-top: 0;
}

.work-link {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(220px, 340px);
  gap: clamp(1.5rem, 4vw, 3.5rem);
  align-items: center;
  padding: clamp(2rem, 5vh, 3rem) 0;
}

.work-meta {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  min-width: 0;
}

.work-num {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-3);
}

.work-title {
  font-size: clamp(1.6rem, 3.2vw, 2.3rem);
  font-weight: 500;
  letter-spacing: -0.025em;
  line-height: 1.1;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  transition: color 0.3s ease;
}

.work-title::after {
  content: "→";
  font-size: 0.7em;
  color: var(--accent);
  opacity: 0;
  transform: translateX(-8px);
  transition: opacity 0.3s ease, transform 0.35s var(--ease-out);
}

.work-link:hover .work-title::after {
  opacity: 1;
  transform: translateX(0);
}

.work-desc {
  color: var(--ink-2);
  max-width: 34em;
  font-size: 0.95rem;
  text-wrap: pretty;
}

.work-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.25rem;
}

.work-tags li {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.05em;
  color: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.28rem 0.7rem;
  transition: border-color 0.25s ease, color 0.25s ease;
}

.work-link:hover .work-tags li {
  color: var(--ink);
}

.work-thumb {
  aspect-ratio: 4 / 3;
  border-radius: 10px;
  overflow: hidden;
  background: var(--bg-soft);
  border: 1px solid var(--line-soft);
}

/* Muted until you commit to it */
.work-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: grayscale(0.7) contrast(1.02) brightness(0.88);
  transition: transform 0.7s var(--ease-out), filter 0.5s ease;
}

.work-link:hover .work-thumb img {
  transform: scale(1.045);
  filter: none;
}

.work-thumb.is-placeholder,
.case-hero.is-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  background:
    radial-gradient(circle at 25% 20%, var(--accent-soft), transparent 55%),
    var(--bg-soft);
}

.placeholder-mark {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  transition: transform 0.6s var(--ease-out);
}

.work-link:hover .placeholder-mark {
  transform: scale(1.04);
}

.pm-glyph {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  letter-spacing: -0.01em;
}

.pm-tag {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
}

@media (max-width: 700px) {
  .work-link {
    grid-template-columns: 1fr;
  }

  .work-thumb {
    order: -1;
  }
}

/* 8. Experience ----------------------------------------------------- */

.exp-list {
  display: flex;
  flex-direction: column;
}

.exp-row {
  display: grid;
  grid-template-columns: minmax(150px, 220px) 1fr;
  gap: 1.5rem 3rem;
  padding: 1.9rem 0;
  border-top: 1px solid var(--line-soft);
}

.exp-row:first-child {
  border-top: 0;
  padding-top: 0;
}

.exp-when {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.5rem;
}

.exp-tag {
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid currentColor;
  border-radius: 999px;
  padding: 0.22rem 0.65rem;
  opacity: 0.9;
}

.exp-date {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--ink-3);
  letter-spacing: 0.02em;
}

.exp-what {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  min-width: 0;
}

.exp-what h3 {
  font-size: 1.08rem;
  font-weight: 550;
  letter-spacing: -0.015em;
  line-height: 1.35;
}

.exp-where {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--ink-3);
  letter-spacing: 0.04em;
}

.exp-what p:not(.exp-where) {
  color: var(--ink-2);
  max-width: 40em;
  font-size: 0.95rem;
  text-wrap: pretty;
}

.exp-what strong {
  color: var(--ink);
}

@media (max-width: 620px) {
  .exp-row {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }

  .exp-when {
    flex-direction: row;
    align-items: center;
  }
}

/* 9. Grids, lists, skills ------------------------------------------- */

.block-grid.two {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
  gap: 2.5rem 4rem;
  align-items: start;
}

@media (max-width: 700px) {
  .block-grid.two {
    grid-template-columns: 1fr;
  }
}

.hairline-list {
  display: flex;
  flex-direction: column;
}

.hairline-list li {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 0.92rem;
  color: var(--ink-2);
}

.hairline-list li:last-child {
  border-bottom: 0;
}

.hairline-list .dot {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  flex: none;
}

.skills-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 2.5rem;
}

.skills-col h4 {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
  padding-bottom: 0.9rem;
  margin-bottom: 0.35rem;
  border-bottom: 1px solid var(--line);
}

.skills-col li {
  padding: 0.55rem 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: 0.92rem;
  color: var(--ink-2);
  transition: color 0.2s ease, padding-left 0.3s var(--ease-out);
}

.skills-col li:hover {
  color: var(--ink);
  padding-left: 0.5rem;
}

.skills-col li:last-child {
  border-bottom: 0;
}

@media (max-width: 700px) {
  .skills-cols {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

/* 10. Contact / footer ---------------------------------------------- */

.connect-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: 2.5rem 4rem;
  align-items: start;
}

.connect-direct {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.quiet-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.quiet-links a {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-2);
  transition: color 0.25s ease;
}

.quiet-links a::after {
  content: "↗";
  margin-left: 0.35em;
  display: inline-block;
  transition: transform 0.3s var(--ease-out);
}

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

.quiet-links a:hover::after {
  transform: translate(2px, -2px);
}

.contact-actions {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 0.75rem;
}

.contact-actions .cta {
  justify-content: center;
}

@media (max-width: 700px) {
  .connect-grid {
    grid-template-columns: 1fr;
  }
}

/* Footer — compact */
.site-foot {
  margin-top: clamp(4rem, 10vh, 7rem);
  border-top: 1px solid var(--line);
}

.foot-inner {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 2rem var(--gutter);
}

.foot-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--ink-3);
}

.foot-links {
  display: flex;
  gap: 1.5rem;
}

.foot-links a {
  color: var(--ink-2);
  transition: color 0.25s ease;
}

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

/* 11. Case study ---------------------------------------------------- */

.case {
  position: relative;
  width: 100%;
  max-width: 880px;
  margin: 0 auto;
  padding: clamp(7.5rem, 18vh, 10rem) var(--gutter) 0;
  flex: 1;
}

.case::before {
  content: "";
  position: absolute;
  top: -10%;
  left: -20%;
  width: 55vw;
  height: 55vw;
  max-width: 700px;
  max-height: 700px;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    rgba(224, 133, 68, 0.1),
    rgba(224, 133, 68, 0.03) 45%,
    transparent 68%
  );
  pointer-events: none;
  z-index: -1;
}

.case-back {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-2);
  margin-bottom: 3rem;
  transition: color 0.25s ease;
}

.case-back::before {
  content: "←";
  transition: transform 0.3s var(--ease-out);
}

.case-back:hover {
  color: var(--accent);
}

.case-back:hover::before {
  transform: translateX(-4px);
}

.case-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1rem;
}

.case h1 {
  font-size: clamp(2.4rem, 6.5vw, 4.25rem);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1.05;
  margin-bottom: 1.5rem;
}

.case-lede {
  font-size: clamp(1.05rem, 1.8vw, 1.2rem);
  color: var(--ink-2);
  max-width: 36em;
  margin-bottom: 2rem;
  text-wrap: pretty;
}

.case-tech {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 2rem;
}

.case-tech li {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.05em;
  color: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.28rem 0.7rem;
}

.case-links {
  margin-bottom: 3rem;
}

.case-hero {
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line-soft);
  background: var(--bg-soft);
  margin-bottom: 1.25rem;
}

.case-hero.is-placeholder {
  aspect-ratio: 16 / 9;
}

.case-hero img {
  width: 100%;
}

.case-gallery {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
  margin-bottom: 1.25rem;
}

.case-gallery figure {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.case-gallery img {
  border-radius: 10px;
  border: 1px solid var(--line-soft);
  background: var(--bg-soft);
  transition: transform 0.5s var(--ease-out);
}

.case-gallery figure:hover img {
  transform: translateY(-4px);
}

.case-gallery figcaption {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-3);
}

@media (max-width: 620px) {
  .case-gallery {
    grid-template-columns: 1fr;
  }
}

.case-body {
  padding-top: 2.5rem;
}

.case-block {
  border-top: 1px solid var(--line-soft);
  padding: 2.5rem 0;
  display: grid;
  grid-template-columns: minmax(140px, 200px) 1fr;
  gap: 1rem 3rem;
}

.case-block h2 {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-3);
  padding-top: 0.3em;
}

.case-block > div,
.case-block p,
.case-block ul {
  color: var(--ink-2);
  max-width: 38em;
  text-wrap: pretty;
}

.case-block p + p {
  margin-top: 1em;
}

.case-block strong {
  color: var(--ink);
}

.case-block ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.case-block ul li {
  position: relative;
  padding-left: 1.4rem;
}

.case-block ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 1px;
  background: var(--accent);
}

@media (max-width: 620px) {
  .case-block {
    grid-template-columns: 1fr;
    gap: 0.75rem;
  }
}

.case-footer {
  border-top: 1px solid var(--line-soft);
  padding: 2.5rem 0 0;
}

/* 12. Back to top --------------------------------------------------- */

.back-to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 90;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ink-2);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s ease, visibility 0.3s ease,
    transform 0.35s var(--ease-out), color 0.25s ease, border-color 0.25s ease;
}

.back-to-top.is-shown {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.back-to-top:hover {
  color: var(--accent);
  border-color: var(--accent);
  transform: translateY(-3px);
}

.back-to-top svg {
  width: 14px;
  height: 14px;
}

/* 13. Focus states -------------------------------------------------- */

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