:root {
  /* gray scale */
  --gray-900: #212529;
  --gray-700: #495057;
  --gray-500: #868e96;
  --gray-300: #dee2e6;
  --gray-200: #e9ecef;
  --gray-100: #f1f3f5;
  --gray-50:  #f8f9fa;
  --text: var(--gray-900);
  --muted: var(--gray-500);
  --line: var(--gray-200);
  --accent: #00457c; /* unitexstudios blue */
  --accent-soft: #e9f1f8;
  --bg: #ffffff;
  --radius: 8px;
  /* type scale */
  --fs-h1: 2.25rem;
  --fs-h2: 1.5rem;
  --fs-h3: 1.0625rem;
  --fs-body: 1rem;
  --fs-small: 0.9375rem;
  --fs-meta: 0.875rem;
  --fs-caption: 0.8125rem;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: "Pretendard Variable", Pretendard, "Apple SD Gothic Neo", "Malgun Gothic", system-ui, sans-serif;
  font-size: var(--fs-body); font-weight: 400;
  color: var(--text); background: var(--bg);
  line-height: 1.7; letter-spacing: -0.01em;
  word-break: keep-all;
}
main { max-width: 820px; margin: 0 auto; padding: clamp(48px, 9vw, 88px) clamp(20px, 4vw, 24px) 96px; }
img { max-width: 100%; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
h1 { font-size: clamp(1.7rem, 1.25rem + 2.2vw, 2.25rem); font-weight: 800; letter-spacing: -0.03em; line-height: 1.25; }
h2 {
  font-size: clamp(1.25rem, 1.1rem + 0.8vw, 1.5rem); font-weight: 700; color: var(--text);
  letter-spacing: -0.02em; line-height: 1.35;
  margin: clamp(56px, 10vw, 88px) 0 22px;
}
h2::after {
  content: ""; display: block; width: 28px; height: 3px;
  background: var(--accent); border-radius: 2px; margin-top: 10px;
}
h3 { font-size: var(--fs-h3); font-weight: 700; letter-spacing: -0.01em; line-height: 1.45; margin: 24px 0 8px; }
p + p { margin-top: 8px; }
p.block { margin-top: 22px; }
ul { padding-left: 20px; }
li { margin: 5px 0; }
.muted { color: var(--muted); font-size: var(--fs-meta); }

/* top bar: back link + language switch */
.topbar {
  display: flex; justify-content: space-between; align-items: center;
  gap: 12px; margin-bottom: 28px;
}
.lang { display: flex; gap: 6px; margin-left: auto; font-size: var(--fs-caption); font-weight: 600; }
.lang a, .lang span {
  display: inline-block; padding: 3px 11px; border-radius: 999px;
  border: 1px solid var(--gray-300); color: var(--gray-700); letter-spacing: 0.02em;
}
.lang .on { background: var(--accent); border-color: var(--accent); color: #fff; }
.lang a:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }

/* hero */
.hero { display: flex; gap: clamp(24px, 5vw, 40px); align-items: center; justify-content: space-between; }
.hero h1 { font-size: clamp(2rem, 1.4rem + 3vw, 2.6rem); }
.hero .en {
  display: block; font-size: 1rem; font-weight: 500;
  color: var(--muted); letter-spacing: 0.02em; margin-top: 6px;
}
.hero .tagline { margin-top: 16px; font-size: 1.1rem; color: var(--text); }
.hero .tagline strong { color: var(--accent); font-weight: 700; }
.hero-sub { margin-top: 4px; color: var(--muted); font-size: var(--fs-small); }
.links { margin-top: 20px; display: flex; gap: 8px; flex-wrap: wrap; }
.hero-photo {
  width: clamp(120px, 20vw, 168px); aspect-ratio: 4 / 5; object-fit: cover; object-position: top;
  border-radius: 12px; border: 1px solid var(--line); flex-shrink: 0;
}

/* buttons */
.btns { display: flex; gap: 8px; margin: 14px 0 4px; flex-wrap: wrap; }
.btn {
  display: inline-block; padding: 5px 14px;
  border: 1px solid var(--gray-300); border-radius: 6px;
  font-size: var(--fs-meta); font-weight: 500;
  background: #fff; color: var(--gray-700);
  transition: border-color 0.15s ease, color 0.15s ease, background 0.15s ease;
}
.btn:hover { border-color: var(--accent); color: var(--accent); background: var(--accent-soft); text-decoration: none; }

/* badges */
.badge {
  display: inline-block; padding: 2px 10px; border-radius: 999px;
  font-size: 0.78rem; font-weight: 600; margin-bottom: 8px;
}
.badge-award { background: var(--accent-soft); color: var(--accent); border: 1px solid #bdd4e7; }
.badge-wip { background: var(--gray-100); color: var(--muted); border: 1px solid var(--line); }

/* project cards */
.cards { display: grid; gap: 16px; }
.card {
  border: 1px solid var(--line); border-radius: var(--radius);
  padding: 20px; background: #fff;
  display: grid; grid-template-columns: 200px 1fr; gap: 20px; align-items: start;
  transition: border-color 0.15s ease;
}
.card:hover { border-color: var(--gray-300); }
.card .thumb {
  width: 100%; aspect-ratio: 3 / 2; object-fit: cover;
  border-radius: 6px; border: 1px solid var(--line);
}
.card h3 { margin: 0 0 4px; }
.card h3 a { color: var(--text); }
.card h3 a:hover { color: var(--accent); text-decoration: none; }
.card .meta { color: var(--muted); font-size: var(--fs-meta); margin-bottom: 6px; }
.card p { font-size: var(--fs-small); }
.card .role { font-size: var(--fs-meta); color: var(--gray-700); margin-top: 6px; }
.card .btns { margin-bottom: 0; }
.subhead {
  margin: 48px 0 14px; font-size: var(--fs-small);
  font-weight: 700; color: var(--muted); letter-spacing: 0.02em;
}

/* timeline */
.timeline { list-style: none; padding: 0; position: relative; }
.timeline::before {
  content: ""; position: absolute; left: 5px; top: 8px; bottom: 8px;
  width: 2px; background: var(--line);
}
.timeline li { position: relative; display: block; margin: 0; padding: 0 0 26px 28px; }
.timeline li:last-child { padding-bottom: 0; }
.timeline li::before {
  content: ""; position: absolute; left: 0; top: 5px;
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--bg); border: 3px solid var(--accent);
}
.timeline li.now::before { background: var(--accent); }
.timeline .when { display: block; font-size: var(--fs-caption); color: var(--muted); margin-bottom: 2px; }

/* skills */
.skills { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px 32px; }
.skill-cat {
  font-size: 0.82rem; font-weight: 700; color: var(--muted);
  letter-spacing: 0.05em; margin: 0 0 10px;
}
.chips { list-style: none; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.chips li {
  padding: 5px 12px; border: 1px solid var(--line); border-radius: 999px;
  font-size: var(--fs-meta); background: var(--gray-50); color: var(--gray-700); margin: 0;
}
.chips li.core {
  border-color: var(--accent); color: var(--accent);
  background: var(--accent-soft); font-weight: 600;
}

/* project detail pages */
.back { display: inline-block; font-size: var(--fs-meta); font-weight: 500; }
.proj-meta {
  display: flex; gap: 16px; flex-wrap: wrap; align-items: center;
  color: var(--muted); font-size: var(--fs-meta); margin: 12px 0 4px;
}
.proj-meta .badge { margin-bottom: 0; }
.gallery { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(240px, 100%), 1fr)); gap: 14px; margin-top: 16px; }
.gallery figure { margin: 0; }
.gallery img {
  width: 100%; aspect-ratio: 4 / 3; object-fit: cover;
  border-radius: 6px; border: 1px solid var(--line);
}
.gallery figcaption { font-size: var(--fs-caption); color: var(--muted); margin-top: 6px; }
.proj-nav {
  display: flex; justify-content: space-between; gap: 16px;
  margin-top: 56px; padding-top: 20px; border-top: 1px solid var(--line);
  font-size: var(--fs-meta); font-weight: 500;
}

footer {
  max-width: 820px; margin: 0 auto; padding: 0 24px 56px;
  color: var(--muted); font-size: var(--fs-caption);
}

@media (max-width: 768px) {
  .card { grid-template-columns: 156px 1fr; gap: 16px; }
}
@media (max-width: 640px) {
  .hero { flex-direction: column-reverse; align-items: flex-start; }
  .card { grid-template-columns: 1fr; }
  .card .thumb { aspect-ratio: 16 / 9; }
  .skills { grid-template-columns: 1fr; gap: 22px; }
  .proj-meta { gap: 8px 16px; }
  .proj-nav { flex-direction: column; gap: 10px; }
  .timeline li { padding-left: 24px; }
}