/* Jake Choi — resume + portfolio
   Neutral personal system. Light/dark via prefers-color-scheme + manual override. */

:root {
  --display: "Inter Tight", "Noto Sans KR", system-ui, sans-serif;
  --sans: "Inter", "Noto Sans KR", system-ui, -apple-system, sans-serif;
  --kr: "Noto Sans KR", system-ui, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --hw: 600; --ht: -0.03em; --h1w: 600; --h1t: -0.035em;
  --bg: #FAFAF8; --bg-2: #F1F1EE; --surface: #FFFFFF;
  --line: rgba(20, 20, 18, 0.10); --line-2: rgba(20, 20, 18, 0.18);
  --text: #141413; --text-2: #5A5A56; --text-3: #8B8B86;
  --accent: #2748D6; --accent-wash: rgba(39, 72, 214, 0.08);
  --r: 12px; --r-sm: 8px; --card-shadow: none; --max: 1040px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111110; --bg-2: #181816; --surface: #1C1C1A;
    --line: rgba(236, 236, 232, 0.10); --line-2: rgba(236, 236, 232, 0.20);
    --text: #ECECE8; --text-2: #A5A5A0; --text-3: #737370;
    --accent: #7D95FF; --accent-wash: rgba(125, 149, 255, 0.12);
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #111110; --bg-2: #181816; --surface: #1C1C1A;
  --line: rgba(236, 236, 232, 0.10); --line-2: rgba(236, 236, 232, 0.20);
  --text: #ECECE8; --text-2: #A5A5A0; --text-3: #737370;
  --accent: #7D95FF; --accent-wash: rgba(125, 149, 255, 0.12);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font-family: var(--sans); font-size: 16px; line-height: 1.65;
  -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility;
  word-break: keep-all; overflow-wrap: anywhere;
}
html[data-lang="ko"] body { font-size: 15.5px; line-height: 1.75; }

/* language switching: blocks tagged data-l="en" / data-l="ko" */
html[data-lang="en"] [data-l="ko"] { display: none !important; }
html[data-lang="ko"] [data-l="en"] { display: none !important; }

a { color: inherit; text-decoration: none; }
a:hover { color: var(--accent); }
p a, li a, dd a { text-decoration: underline; text-decoration-color: var(--line-2); text-underline-offset: 3px; }
p a:hover { text-decoration-color: var(--accent); }
img { max-width: 100%; height: auto; display: block; }
h1, h2, h3, h4 { font-family: var(--display); font-weight: var(--hw); letter-spacing: var(--ht); line-height: 1.12; margin: 0; text-wrap: balance; }
html[data-lang="ko"] h1, html[data-lang="ko"] h2, html[data-lang="ko"] h3, html[data-lang="ko"] h4 { font-family: var(--kr); font-weight: 700; letter-spacing: -0.01em; line-height: 1.3; }
p { margin: 0 0 1em; }
.muted { color: var(--text-2); }
.mono { font-family: var(--mono); font-size: 12.5px; letter-spacing: 0.04em; text-transform: uppercase; color: var(--text-3); }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 clamp(16px, 4vw, 32px); }

/* nav */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: saturate(160%) blur(10px); -webkit-backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 56px; gap: 16px; }
.brand { font-family: var(--display); font-size: 17px; font-weight: 700; letter-spacing: -0.02em; white-space: nowrap; }
.nav-links { display: flex; align-items: center; gap: 22px; font-size: 14px; color: var(--text-2); }
.nav-links a:hover { color: var(--text); }
.controls { display: flex; align-items: center; gap: 8px; }
.seg { display: inline-flex; border: 1px solid var(--line-2); border-radius: 999px; padding: 2px; }
.seg button {
  appearance: none; border: 0; background: transparent; color: var(--text-2);
  font: 600 12px var(--mono); letter-spacing: 0.06em; padding: 5px 10px; border-radius: 999px; cursor: pointer;
}
.seg button[aria-pressed="true"] { background: var(--text); color: var(--bg); }
.icon-btn {
  appearance: none; border: 1px solid var(--line-2); background: transparent; color: var(--text-2);
  width: 32px; height: 32px; border-radius: 999px; cursor: pointer; display: grid; place-items: center;
}
.icon-btn:hover { color: var(--text); border-color: var(--text-3); }
.icon-btn svg { width: 15px; height: 15px; }
@media (max-width: 640px) { .nav-links { display: none; } }

/* hero */
.hero { padding: clamp(56px, 10vw, 112px) 0 clamp(40px, 6vw, 72px); border-bottom: 1px solid var(--line); }
.hero h1 { font-size: clamp(38px, 6.5vw, 76px); font-weight: var(--h1w); letter-spacing: var(--h1t); line-height: 1.02; max-width: 16ch; }
.hero h1 em { font-style: normal; color: var(--accent); }
.hero .lede { font-size: clamp(17px, 2vw, 20px); color: var(--text-2); max-width: 60ch; margin-top: 24px; }
.hero .meta { display: flex; flex-wrap: wrap; gap: 10px 28px; margin-top: 32px; font-size: 14px; color: var(--text-2); }
.hero .meta a { color: var(--text); border-bottom: 1px solid var(--line-2); }
.hero .meta a:hover { color: var(--accent); border-color: var(--accent); }

/* sections */
section { padding: clamp(48px, 7vw, 88px) 0; border-bottom: 1px solid var(--line); }
section:last-of-type { border-bottom: 0; }
.sec-head { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; margin-bottom: clamp(24px, 4vw, 40px); }
.sec-head h2 { font-size: clamp(26px, 3.6vw, 36px); }
.sec-head .mono { flex-shrink: 0; }

/* work cards */
.work-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.card {
  display: flex; flex-direction: column; gap: 14px;
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--r); padding: 22px; box-shadow: var(--card-shadow);
  transition: border-color .15s, transform .15s;
}
.card:hover { border-color: var(--text-3); transform: translateY(-2px); color: inherit; }
.card .thumb { aspect-ratio: 16/9; border-radius: var(--r-sm); overflow: hidden; border: 1px solid var(--line); background: var(--bg-2); }
.card .thumb img { width: 100%; height: 100%; object-fit: cover; object-position: top; }

.card h3 { font-size: 22px; }
.card p { color: var(--text-2); font-size: 15px; margin: 0; }
.card .tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: auto; }
.tag { font: 500 12px var(--mono); letter-spacing: 0.03em; color: var(--text-2); border: 1px solid var(--line-2); border-radius: 999px; padding: 3px 9px; }
.card .cta { color: var(--accent); font-size: 14px; font-weight: 500; }

/* experience */
.xp { display: grid; grid-template-columns: 180px 1fr; gap: 12px 32px; padding: 28px 0; border-top: 1px solid var(--line); }
.xp:first-of-type { border-top: 0; padding-top: 0; }
.xp .when { font-family: var(--mono); font-size: 12.5px; color: var(--text-3); letter-spacing: 0.03em; padding-top: 6px; }
.xp .when span { display: block; margin-top: 4px; }
.xp h3 { font-size: 22px; }
.xp .role { color: var(--text-2); margin: 2px 0 12px; font-size: 15px; }
.xp .role a { color: var(--text-3); }
.xp .blurb { color: var(--text-2); font-size: 15px; }
.xp ul { margin: 10px 0 0; padding-left: 18px; color: var(--text); font-size: 15px; }
.xp li { margin: 5px 0; }
.xp li::marker { color: var(--text-3); }
.xp h4 { font-family: var(--mono); font-size: 12px; letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3); margin: 16px 0 4px; }
@media (max-width: 640px) { .xp { grid-template-columns: 1fr; gap: 6px; } }

/* awards + misc */
.cols { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 32px; }
dl { margin: 0; }
dl div { display: flex; justify-content: space-between; gap: 16px; padding: 10px 0; border-bottom: 1px solid var(--line); font-size: 15px; }
dt { font-weight: 500; white-space: nowrap; }
dd { margin: 0; color: var(--text-2); text-align: right; }
.stat-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 16px; }
.stat { border-top: 2px solid var(--text); padding-top: 12px; }
.stat b { display: block; font-family: var(--display); font-size: 34px; font-weight: var(--hw); line-height: 1; letter-spacing: -0.03em; font-variant-numeric: tabular-nums; }
.stat span { display: block; margin-top: 6px; font-size: 13.5px; color: var(--text-2); }

footer { padding: 40px 0 56px; color: var(--text-3); font-size: 13.5px; display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; }

/* case study pages */
.case-hero { padding: clamp(40px, 7vw, 80px) 0 clamp(28px, 4vw, 48px); border-bottom: 1px solid var(--line); }
.case-hero .crumbs { font-size: 14px; color: var(--text-3); margin-bottom: 20px; }
.case-hero .crumbs a:hover { color: var(--accent); }
.case-hero h1 { font-size: clamp(32px, 5vw, 56px); font-weight: var(--h1w); letter-spacing: var(--h1t); line-height: 1.05; max-width: 22ch; }
.case-hero .lede { font-size: clamp(17px, 2vw, 20px); color: var(--text-2); max-width: 64ch; margin-top: 18px; }
.facts { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 12px 24px; margin-top: 28px; font-size: 14px; }
.facts .k { display: block; font-family: var(--mono); font-size: 11.5px; letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3); margin-bottom: 3px; }
.prose { max-width: 700px; }
.wrap.prose { max-width: var(--max); }
.wrap.prose > * { max-width: 700px; }
.wrap.prose > .facts { max-width: 760px; }
.prose h2 { font-size: clamp(24px, 3vw, 30px); margin: 0 0 14px; }
.prose h3 { font-size: 20px; margin: 22px 0 8px; }
.prose p, .prose li { color: var(--text-2); font-size: 16px; }
html[data-lang="ko"] .prose p, html[data-lang="ko"] .prose li { font-size: 15.5px; }
.prose ul { padding-left: 20px; }
.prose li { margin: 6px 0; }
.prose strong { color: var(--text); font-weight: 600; }
.figure { margin: 28px 0; }
.figure .frame { border: 1px solid var(--line); border-radius: var(--r); overflow: hidden; background: #0B0E0C; }
.figure figcaption { margin-top: 10px; font-size: 13.5px; color: var(--text-3); }
.figure figcaption b { color: var(--text-2); font-weight: 500; }
.callout { border-left: 2px solid var(--accent); background: var(--accent-wash); padding: 14px 18px; border-radius: 0 8px 8px 0; margin: 20px 0; }
.callout p { margin: 0; color: var(--text); }
.flow { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 10px; margin: 20px 0; counter-reset: step; }
.flow div { border: 1px solid var(--line); border-radius: 10px; padding: 12px 14px; background: var(--surface); font-size: 14px; }
.flow div::before { counter-increment: step; content: counter(step, decimal-leading-zero); display: block; font-family: var(--mono); font-size: 11px; color: var(--text-3); margin-bottom: 6px; }
.flow div b { display: block; font-weight: 600; margin-bottom: 2px; }
.flow div span { color: var(--text-2); font-size: 13px; }
.decision { display: grid; grid-template-columns: 110px 1fr; gap: 8px 20px; padding: 18px 0; border-top: 1px solid var(--line); }
.decision:last-child { border-bottom: 1px solid var(--line); }
.decision .k { font-family: var(--mono); font-size: 11.5px; letter-spacing: 0.06em; text-transform: uppercase; color: var(--text-3); padding-top: 5px; }
.decision h3 { margin: 0 0 4px; font-size: 18px; }
.decision p { margin: 0; }
@media (max-width: 560px) { .decision { grid-template-columns: 1fr; gap: 2px; } }
.pager { display: flex; justify-content: space-between; gap: 16px; padding: 32px 0 0; font-size: 15px; }
.pager a { color: var(--text-2); }
.pager a:hover { color: var(--accent); }
.note { font-size: 13.5px; color: var(--text-3); }

/* phone screenshot grids */
.phones { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 18px; margin: 28px 0; }
.phones figure { margin: 0; }
.phones img { width: 100%; border-radius: 14px; border: 1px solid var(--line); background: var(--bg-2); }
.phones figcaption { margin-top: 8px; font-size: 13px; color: var(--text-3); }
.phones figcaption b { color: var(--text-2); font-weight: 500; }
.phones.dark img { background: #111; }