/* Case studies: one page per system, in the v7 paper-and-ink language.
   Built for a hiring manager's second click: the problem, my role, the system drawn out, what changed. */

:root {
  --paper: #edeae4;
  --paper-hi: #f7f6f2;
  --paper-lo: #e2ddd4;
  --ink: #161412;
  --ink-2: #3c3732;
  --ink-3: #7a7268;
  --rule: rgba(22, 20, 18, .14);
  --sun: #e2432a;
  --serif: 'Instrument Serif', 'Times New Roman', serif;
  --sans: 'Inter Tight', system-ui, -apple-system, sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, monospace;
  --edge: max(clamp(16px, 4vw, 56px), calc((100vw - 1280px) / 2));
  --ease: cubic-bezier(.2, .7, .1, 1);
  color-scheme: light;
}
@view-transition { navigation: auto; }

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; overflow-x: clip; }
body { margin: 0; background: var(--paper); color: var(--ink); font: 400 18px/1.6 var(--sans); letter-spacing: -.005em; -webkit-font-smoothing: antialiased; }
img, svg { display: block; max-width: 100%; }
a { color: inherit; }
h1, h2, h3, p, dl, dd, ol, ul, figure, blockquote { margin: 0; }
ol, ul { padding: 0; list-style: none; }
em { font-family: var(--serif); font-style: italic; font-weight: 400; }
::selection { background: var(--ink); color: var(--paper); }
:focus-visible { outline: 2px solid var(--ink); outline-offset: 3px; }
.mono { font-family: var(--mono); font-size: 12px; letter-spacing: .07em; text-transform: uppercase; }
.skip { position: fixed; left: 12px; top: -60px; z-index: 200; padding: 10px 16px; background: var(--ink); color: var(--paper); border-radius: 999px; text-decoration: none; }
.skip:focus { top: 12px; }

.btn { display: inline-flex; align-items: center; gap: 8px; padding: 14px 22px; border-radius: 999px; font: 500 15px/1 var(--sans); text-decoration: none; transition: background .3s var(--ease), color .3s var(--ease), transform .3s var(--ease); }
.btn:hover { transform: translateY(-2px); }
.btn-ink { background: var(--ink); color: var(--paper); }
.btn-line { border: 1.5px solid var(--ink); }
.btn-line:hover { background: var(--ink); color: var(--paper); }

/* ---------- header ---------- */
.head { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 14px var(--edge); background: color-mix(in srgb, var(--paper) 86%, transparent); -webkit-backdrop-filter: blur(12px); backdrop-filter: blur(12px); box-shadow: 0 1px 0 var(--rule); }
.wordmark { font: 400 23px/1 var(--serif); text-decoration: none; letter-spacing: -.01em; view-transition-name: wordmark; }
.head nav ul { display: flex; gap: clamp(14px, 2vw, 28px); }
.head nav a { font: 500 12px var(--mono); letter-spacing: .08em; text-transform: uppercase; text-decoration: none; }
.head nav a:hover { text-decoration: underline; text-underline-offset: 4px; }
.status { display: inline-flex; align-items: center; gap: 8px; padding: 9px 14px; border: 1.5px solid var(--ink); border-radius: 999px; font: 500 12px var(--mono); letter-spacing: .08em; text-transform: uppercase; text-decoration: none; }
.status:hover { background: var(--ink); color: var(--paper); }
.live { width: 8px; height: 8px; border-radius: 50%; background: var(--sun); }

/* ---------- hero ---------- */
.hero { padding: clamp(56px, 9vw, 120px) var(--edge) clamp(40px, 6vw, 72px); display: grid; gap: 26px; }
.crumb { display: flex; flex-wrap: wrap; gap: 10px 18px; color: var(--ink-3); }
.crumb b { color: var(--sun); font-weight: 500; }
.hero h1 { font: 400 clamp(46px, 7.4vw, 120px)/.92 var(--serif); letter-spacing: -.03em; max-width: 18ch; text-wrap: balance; view-transition-name: case-title; }
.kpi { display: flex; align-items: baseline; flex-wrap: wrap; gap: 8px 22px; margin-top: 10px; padding-top: 26px; border-top: 1px solid var(--rule); }
.kpi b { font: 400 clamp(64px, 9vw, 150px)/.85 var(--serif); letter-spacing: -.04em; }
.kpi b i { font-style: normal; color: var(--sun); }
.kpi span { max-width: 26ch; color: var(--ink-2); }
.meta { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 18px 28px; margin-top: 16px; }
.meta dt { color: var(--ink-3); margin-bottom: 6px; }
.meta dd { font-size: 16px; line-height: 1.45; }

/* ---------- body ---------- */
.part { display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); gap: 18px clamp(28px, 5vw, 80px); padding: clamp(48px, 6vw, 88px) var(--edge); border-top: 1px solid var(--rule); }
.part > header { display: grid; gap: 10px; align-content: start; }
.part > header .mono { color: var(--sun); }
.part h2 { font: 400 clamp(32px, 3.6vw, 56px)/.98 var(--serif); letter-spacing: -.02em; }
.part .lead { font: 400 clamp(26px, 2.6vw, 40px)/1.15 var(--serif); letter-spacing: -.01em; text-wrap: pretty; }
.part p + p, .part .lead + p { margin-top: 18px; }
.part p { max-width: 62ch; color: var(--ink-2); }
.part .lead { color: var(--ink); }
.built { display: grid; gap: 0; counter-reset: b; }
.built li { counter-increment: b; display: grid; grid-template-columns: 44px 1fr; gap: 14px; padding: 18px 0; border-bottom: 1px solid var(--rule); }
.built li:first-child { padding-top: 4px; }
.built li::before { content: counter(b, decimal-leading-zero); font: 500 12px/2 var(--mono); color: var(--ink-3); }
.built b { font-weight: 600; }

/* the system, drawn as a loop of steps */
.system { position: relative; display: grid; grid-template-columns: repeat(var(--n, 5), minmax(0, 1fr)); gap: 12px; padding: 28px 0 54px; }
.step { position: relative; display: grid; gap: 8px; align-content: start; padding: 18px 16px 20px; border-radius: 6px; background: var(--paper-hi); box-shadow: inset 0 0 0 1px var(--rule); transition: background .35s, color .35s, transform .35s var(--ease); }
.step::after { content: '→'; position: absolute; right: -11px; top: 50%; translate: 0 -50%; z-index: 1; font: 400 16px var(--mono); color: var(--ink-3); }
.step:last-of-type::after { display: none; }
.step .mono { color: var(--ink-3); font-size: 10.5px; }
.step b { font: 400 22px/1.05 var(--serif); }
.step small { font-size: 13.5px; line-height: 1.4; color: var(--ink-2); }
.step.is-on { background: var(--ink); color: var(--paper); transform: translateY(-4px); }
.step.is-on .mono, .step.is-on small { color: rgba(237, 234, 228, .72); }
.loop { position: absolute; left: 6%; right: 6%; bottom: 8px; height: 34px; border: 1.5px dashed var(--ink-3); border-top: 0; border-radius: 0 0 20px 20px; }
.loop::before { content: ''; position: absolute; left: -6px; top: -8px; border: 6px solid transparent; border-bottom: 8px solid var(--ink-3); }
.loop span { position: absolute; left: 50%; bottom: -9px; translate: -50% 0; padding: 0 10px; background: var(--paper); font: 500 10.5px var(--mono); letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); }
.branch { margin-top: 6px; padding: 12px 14px; border-left: 2px solid var(--sun); background: rgba(226, 67, 42, .06); font-size: 15px; color: var(--ink-2); }

.results { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 12px; }
.result { padding: 22px 20px; border-radius: 6px; background: var(--paper-hi); box-shadow: inset 0 0 0 1px var(--rule); }
.result b { display: block; font: 400 clamp(46px, 5vw, 76px)/.9 var(--serif); letter-spacing: -.03em; }
.result span { display: block; margin-top: 10px; font-size: 15px; color: var(--ink-2); }

.principle { padding: clamp(64px, 9vw, 130px) var(--edge); background: var(--ink); color: var(--paper); text-align: center; }
.principle .mono { color: var(--sun); }
.principle blockquote { margin: 18px auto 0; max-width: 22ch; font: 400 clamp(38px, 5.6vw, 92px)/1 var(--serif); letter-spacing: -.025em; }
.principle p:last-child { margin: 26px auto 0; max-width: 56ch; color: rgba(237, 234, 228, .72); }

.craft { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; }
.craft img { width: 100%; aspect-ratio: 4 / 5; object-fit: cover; border-radius: 3px; }
.craft figcaption { grid-column: 1 / -1; color: var(--ink-3); }

/* ---------- next + contact ---------- */
.next { display: grid; grid-template-columns: 1fr auto; align-items: end; gap: 24px; padding: clamp(56px, 7vw, 100px) var(--edge); border-top: 1px solid var(--rule); text-decoration: none; transition: background .4s; }
.next:hover { background: var(--paper-hi); }
.next .mono { color: var(--ink-3); }
.next b { display: block; margin-top: 12px; font: 400 clamp(36px, 5.4vw, 88px)/.95 var(--serif); letter-spacing: -.03em; max-width: 18ch; }
.next i { font: 400 clamp(48px, 6vw, 96px)/1 var(--serif); font-style: normal; transition: transform .4s var(--ease); }
.next:hover i { transform: translateX(10px); }
.contact { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 20px; padding: 40px var(--edge) 56px; border-top: 1px solid var(--rule); }
.contact p { font: 400 clamp(26px, 2.6vw, 38px)/1.1 var(--serif); }
.contact div { display: flex; flex-wrap: wrap; gap: 10px; }
.foot { padding: 0 var(--edge) 28px; color: var(--ink-3); }

/* reveal on scroll (only when JS is on) */
.js .rv { opacity: 0; transform: translateY(24px); transition: opacity .9s var(--ease), transform .9s var(--ease); }
.js .rv.is-in { opacity: 1; transform: none; }

::view-transition-old(root) { animation: .35s var(--ease) both vt-out; }
::view-transition-new(root) { animation: .55s var(--ease) both vt-in; }
@keyframes vt-out { to { opacity: 0; transform: translateY(-14px); } }
@keyframes vt-in { from { opacity: 0; transform: translateY(18px); } }

@media (max-width: 900px) {
  .part { grid-template-columns: minmax(0, 1fr); }
  .meta { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .system { grid-template-columns: minmax(0, 1fr); padding-bottom: 20px; }
  .step::after { content: '↓'; right: auto; left: 22px; top: auto; bottom: -15px; translate: none; }
  .loop { display: none; }
  .craft { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .head nav { display: none; }
  .wordmark { font-size: 20px; }
  .status { padding: 7px 11px; font-size: 10.5px; }
  .next { grid-template-columns: 1fr; }
  .next i { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  .js .rv { opacity: 1; transform: none; transition: none; }
  ::view-transition-old(root), ::view-transition-new(root) { animation: none; }
  .step { transition: none; }
}