:root {
  --paper: #f3f0e8;
  --paper-light: #fbfaf5;
  --ink: #141414;
  --muted: #66645e;
  --line: #cbc7bd;
  --blue: #3155e7;
  --blue-dark: #203bb3;
  --lime: #d9ff43;
  --coral: #ff6b52;
  --max: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 5rem; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "DM Sans", "Noto Sans KR", sans-serif;
  line-height: 1.7;
  word-break: keep-all;
  overflow-wrap: anywhere;
}
a { color: inherit; text-decoration: none; }
a:focus-visible { outline: 3px solid rgba(49, 85, 231, .35); outline-offset: 4px; }
::selection { color: var(--ink); background: var(--lime); }
.skip-link { position: fixed; top: -5rem; left: 1rem; z-index: 100; padding: .65rem 1rem; color: white; background: var(--blue); }
.skip-link:focus { top: 1rem; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  width: min(calc(100% - 2rem), var(--max));
  align-items: center;
  justify-content: space-between;
  margin: 0 auto;
  padding: 1rem 0;
  border-bottom: 1px solid rgba(203, 199, 189, .92);
  background: rgba(243, 240, 232, .9);
  backdrop-filter: blur(14px);
}
.brand { font-size: .72rem; font-weight: 800; line-height: .9; letter-spacing: -.03em; }
.brand span { color: var(--blue); }
nav { display: flex; align-items: center; gap: 1.7rem; font-size: .875rem; font-weight: 700; }
nav a { transition: color .18s; }
nav a:hover { color: var(--blue); }
.nav-github { padding: .55rem .8rem; color: white; background: var(--ink); }

main, footer { width: min(calc(100% - 2rem), var(--max)); margin: 0 auto; }
.section-index { margin: 0; color: var(--blue); font-size: .875rem; font-weight: 700; letter-spacing: .08em; }
h1, h2, h3 { margin-top: 0; line-height: 1.1; letter-spacing: -.055em; }

.hero {
  display: grid;
  min-height: 0;
  grid-template-columns: minmax(0, 1.6fr) minmax(260px, .75fr);
  gap: clamp(2rem, 5vw, 6rem);
  align-items: center;
  padding: 3rem 0;
}
.kicker { display: flex; max-width: 640px; justify-content: space-between; margin: 0 0 1.5rem; color: var(--muted); font-size: .66rem; font-weight: 800; letter-spacing: .13em; }
.hero h1 { max-width: 850px; margin-bottom: 1.7rem; font-size: clamp(2.8rem, 5vw, 4.4rem); font-weight: 600; word-break: keep-all; }
.hero h1 span, .hero h1 strong { display: block; }
.hero h1 span { font-weight: 500; }
.hero h1 strong { position: relative; width: fit-content; color: var(--blue); font-weight: 800; }

.hero-lead { max-width: 650px; margin: 0; color: var(--muted); font-size: clamp(1rem, 1.65vw, 1.2rem); word-break: keep-all; }
.hero-actions { display: flex; flex-wrap: wrap; gap: .8rem; margin-top: 2.3rem; }
.button { display: inline-flex; align-items: center; gap: 1rem; padding: .83rem 1.05rem; font-size: .78rem; font-weight: 800; transition: transform .18s, background .18s; }
.button:hover { transform: translateY(-2px); }
.button-primary { color: white; background: var(--blue); }
.button-primary:hover { background: var(--blue-dark); }
.button-quiet { border: 1px solid var(--line); background: rgba(255, 255, 255, .28); }
.button-dark { color: white; background: var(--ink); }

.identity-card { align-self: center; border-top: 3px solid var(--blue); border-bottom: 1px solid var(--line); background: var(--paper-light); }
.identity-card dl { margin: 0; }
.identity-card dl > div { display: grid; grid-template-columns: 5.5rem 1fr; gap: 1rem; padding: 1rem 1.1rem; border-top: 1px solid var(--line); }
.identity-card dl > div:first-child { border-top: 0; }
.identity-card dt { color: var(--blue); font-size: .875rem; font-weight: 700; letter-spacing: 0; text-transform: uppercase; }
.identity-card dd { margin: 0; font-size: .9375rem; font-weight: 500; line-height: 1.7; }

.statement { padding: 4rem 0; border-top: 1px solid var(--ink); }
.statement-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(3rem, 8vw, 8rem); margin-top: 2rem; }
.statement h2 { margin: 0; font-size: clamp(2rem, 3.5vw, 3rem); font-weight: 700; word-break: keep-all; }
.statement-copy { max-width: 560px; color: var(--muted); font-size: 1rem; }
.statement-copy p { margin: 0 0 1.3rem; }
.statement-note { padding: 1.1rem 1.25rem; color: var(--ink); border-left: 4px solid var(--lime); background: var(--paper-light); font-weight: 600; }

.section-heading { display: grid; grid-template-columns: 1fr 1fr; align-items: end; margin-bottom: 3rem; }
.section-heading .section-index { grid-column: 1 / -1; margin-bottom: 1.2rem; }
.section-heading h2 { margin: 0; font-size: clamp(2rem, 3.5vw, 3rem); }
.section-heading > p:last-child { max-width: 360px; justify-self: end; margin: 0; color: var(--muted); font-size: .9rem; }
.work { padding: 3.5rem 0; border-top: 1px solid var(--ink); }
.work-heading h2 { max-width: 740px; }
.project-list { border-top: 1px solid var(--ink); }
.project-group-label { margin: 0; padding: .8rem 1.6rem; color: white; background: var(--ink); font-size: .66rem; font-weight: 800; letter-spacing: .12em; }
.project-group-secondary { color: var(--ink); border: 1px solid var(--ink); border-top: 0; background: var(--lime); }
.project { position: relative; display: grid; grid-template-columns: 2.5rem minmax(0, 1fr) 10rem; gap: 2rem; min-height: 0; padding: 1.8rem 1.6rem; border-bottom: 1px solid var(--ink); overflow: hidden; background: var(--paper-light); transition: color .22s, background .22s; }

.project:hover { color: white; background: var(--blue); }
.project:hover::after { border-color: rgba(255,255,255,.35); transform: scale(1.25); }
.project:hover .project-type, .project:hover .project-body > p, .project:hover .project-number { color: rgba(255,255,255,.76); }
.project:hover .project-proof li { color: var(--ink); background: var(--lime); }
.project-number { color: var(--blue); font-size: .72rem; font-weight: 800; }
.project-body { position: relative; z-index: 1; max-width: 700px; }
.project-type { margin: 0 0 .8rem; color: var(--muted); font-size: .875rem; font-weight: 800; letter-spacing: .1em; }
.project h3 { margin-bottom: 1.2rem; font-size: clamp(1.75rem, 2.8vw, 2.5rem); }
.project-body > p { max-width: 660px; margin: 0; color: var(--muted); font-size: 1rem; }
.project-proof { display: flex; flex-wrap: wrap; gap: .45rem; margin: 1.5rem 0 0; padding: 0; list-style: none; }
.project-proof li { padding: .35rem .55rem; color: var(--blue-dark); background: #e4e8ff; font-size: .875rem; font-weight: 700; }
.project-link { position: relative; z-index: 1; align-self: end; justify-self: end; font-size: .875rem; font-weight: 800; }
.project-link span { display: inline-block; margin-left: .4rem; font-size: 1.05rem; transition: transform .18s; }
.project-link:hover span { transform: translate(3px, -3px); }

.experience { padding: 3.5rem 0; border-top: 1px solid var(--line); }
.experience-layout { display: grid; grid-template-columns: 1.25fr .75fr; gap: clamp(3rem, 8vw, 8rem); }
.timeline article { display: grid; grid-template-columns: 8.5rem 1fr; gap: 1.5rem; padding: 1.7rem 0; border-top: 1px solid var(--line); }
.timeline article:last-child { border-bottom: 1px solid var(--line); }
.timeline time { color: var(--blue); font-size: .7rem; font-weight: 800; }
.timeline h3 { margin-bottom: .55rem; font-size: 1.4rem; }
.timeline p { margin: 0; color: var(--muted); font-size: 1rem; }
.credentials { align-self: start; padding: 1.5rem; color: white; background: var(--ink); }
.credentials-label { margin: 0 0 2rem; color: var(--lime); font-size: .66rem; font-weight: 800; letter-spacing: .12em; }
.credentials > div { padding: 1rem 0; border-top: 1px solid #3f3f3f; }
.credentials span { display: block; margin-bottom: .35rem; color: #9f9f9f; font-size: .63rem; text-transform: uppercase; }
.credentials strong { font-size: .9375rem; font-weight: 600; }

.closing { display: grid; grid-template-columns: .3fr 1fr; gap: 2rem; padding: 4rem 0; border-top: 1px solid var(--ink); }
.closing h2 { max-width: 900px; margin-bottom: 1.5rem; font-size: clamp(2rem, 4vw, 3.4rem); }
.closing > div > p { max-width: 620px; margin: 0 0 2rem; color: var(--muted); }
.contact-actions { display: flex; flex-wrap: wrap; gap: .7rem; }

footer { display: grid; grid-template-columns: 1fr 1fr 1fr; padding: 1.5rem 0 2rem; border-top: 1px solid var(--line); color: var(--muted); font-size: .68rem; }
footer span:nth-child(2) { justify-self: center; }
footer a { justify-self: end; }
footer > a:first-of-type { justify-self: center; }
footer a:hover { color: var(--blue); }


@media (max-width: 900px) {
  .hero { min-height: auto; grid-template-columns: 1fr; padding-top: 4.5rem; }
  .identity-card { min-height: auto; }
  .identity-visual { min-height: 280px; }
  .statement-grid, .experience-layout { grid-template-columns: 1fr; }
  .method-list { grid-template-columns: repeat(2, 1fr); }
  .method-list li:nth-child(2) { border-right: 0; }
  .method-list li:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .project { grid-template-columns: 3.5rem minmax(0, 1fr); }
  .project-link { grid-column: 2; justify-self: start; }
  .closing { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  nav { gap: .65rem; font-size: .68rem; }
  nav a[href="#about"] { display: none; }
  .nav-github { padding: .48rem .62rem; }
  .hero { gap: 3rem; padding: 2.2rem 0; }
  .kicker { margin-bottom: 1.5rem; }
  .hero h1 { font-size: clamp(2.4rem, 10vw, 3.2rem); }
  .hero h1 strong::after { right: 0; }
  .hero-lead { font-size: .97rem; }
  .identity-card dl > div { grid-template-columns: 4.8rem 1fr; }
  .statement, .method, .work, .experience, .closing { padding: 3rem 0; }
  .statement-grid { gap: 2rem; margin-top: 2rem; }
  .section-heading { grid-template-columns: 1fr; gap: 1rem; }
  .section-heading .section-index { margin-bottom: .4rem; }
  .section-heading > p:last-child { justify-self: start; }
  .method-list { grid-template-columns: 1fr; }
  .method-list li, .method-list li:nth-child(2) { min-height: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .method-list h3 { margin-top: 2.2rem; }
  .project { grid-template-columns: 1fr; gap: 1rem; min-height: auto; padding: 1.6rem 1.1rem 2rem; }
  .project-number { margin-bottom: .8rem; }
  .project-link { grid-column: 1; margin-top: 1rem; }
  .project::after { right: -100px; }
  .timeline article { grid-template-columns: 1fr; gap: .7rem; }
  footer { grid-template-columns: 1fr auto; }
  footer > a:first-of-type { grid-column: 1 / -1; grid-row: 2; justify-self: start; margin-top: .45rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
  }