/* ---------- Theme tokens ---------- */
:root {
  --bg: #ffffff;
  --fg: #1a202c;
  --muted: #4a5568;
  --accent: #88ccca;
  --accent-strong: #319795;
  --card-bg: #ffffff;
  --card-border: rgba(0, 0, 0, 0.08);
  --card-hover-bg: #f7fafc;
  --navbar-bg: rgba(255, 255, 255, 0.4);
  --section-divider: rgba(0, 0, 0, 0.08);
}

[data-theme="dark"] {
  --bg: #202023;
  --fg: #e2e8f0;
  --muted: #a0aec0;
  --accent: #88ccca;
  --accent-strong: #4fd1c5;
  --card-bg: rgba(255, 255, 255, 0.04);
  --card-border: rgba(255, 255, 255, 0.12);
  --card-hover-bg: rgba(255, 255, 255, 0.08);
  --navbar-bg: rgba(32, 32, 35, 0.5);
  --section-divider: rgba(255, 255, 255, 0.1);
}

/* ---------- Base ---------- */
* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans KR",
    "Apple SD Gothic Neo", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.2s ease, color 0.2s ease;
}

a {
  color: var(--accent-strong);
  text-decoration: none;
}
a:hover { text-decoration: underline; }

h1, h2, h3, h4 {
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0;
}

p { margin: 0 0 1em 0; }

/* ---------- Layout ---------- */
.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 20px;
}

main {
  padding-top: 88px;   /* leave room for fixed navbar */
  padding-bottom: 60px;
}

/* ---------- Navbar ---------- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 10;
  background: var(--navbar-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--section-divider);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 12px;
  padding-bottom: 12px;
}

.brand {
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--fg);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
  margin-right: 12px;
}

.nav-link {
  padding: 6px 10px;
  border-radius: 6px;
  color: var(--fg);
  font-size: 0.95rem;
}
.nav-link:hover { text-decoration: none; background: var(--card-hover-bg); }
.nav-link.active {
  background: var(--accent);
  color: #202023;
}

#theme-toggle {
  background: transparent;
  border: 1px solid var(--card-border);
  color: var(--fg);
  width: 36px;
  height: 36px;
  border-radius: 8px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1.05rem;
  transition: background 0.15s ease;
}
#theme-toggle:hover { background: var(--card-hover-bg); }

/* ---------- Greeting box (home) ---------- */
.greeting-box {
  background: var(--navbar-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 14px 18px;
  text-align: center;
  font-size: 1.05rem;
  margin-bottom: 28px;
  min-height: 52px;
}

.cursor {
  display: inline-block;
  width: 2px;
  background: var(--fg);
  margin-left: 2px;
  animation: blink 1s steps(2) infinite;
  vertical-align: -2px;
  height: 1em;
}
@keyframes blink { 50% { opacity: 0; } }

/* ---------- Section / headings ---------- */
.section { margin-bottom: 36px; }

.page-title {
  font-size: 1.8rem;
  margin-bottom: 18px;
  padding-bottom: 6px;
}

.section-title {
  font-size: 1.2rem;
  color: var(--accent-strong);
  border-bottom: 4px solid var(--accent);
  display: inline-block;
  padding-bottom: 2px;
  margin: 24px 0 12px;
}

.subsection-title {
  font-size: 1rem;
  margin: 18px 0 10px;
  color: var(--muted);
}

/* ---------- Skill cards ---------- */
.skill-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
  gap: 12px;
}

.skill-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  padding: 16px 8px;
  text-align: center;
  font-size: 0.92rem;
  font-weight: 600;
  transition: transform 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
  cursor: default;
}
.skill-card:hover {
  transform: translateY(-3px);
  background: var(--card-hover-bg);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}
.skill-card .badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--muted);
  margin-top: 2px;
}

/* ---------- Bio timeline ---------- */
.bio-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.bio-item {
  display: flex;
  gap: 14px;
  padding: 6px 0;
  align-items: baseline;
}
.bio-year {
  flex: 0 0 auto;
  font-variant-numeric: tabular-nums;
  color: var(--muted);
  font-size: 0.9rem;
  min-width: 170px;
}
.bio-body { flex: 1; }

/* ---------- Contact ---------- */
.contact-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.contact-list li {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 0;
}

/* ---------- Footer ---------- */
.footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
  padding: 24px 0 8px;
  border-top: 1px solid var(--section-divider);
}

/* ---------- 404 ---------- */
.notfound {
  text-align: center;
  padding: 40px 0;
}
.notfound h2 {
  font-size: 2rem;
  margin-bottom: 12px;
}
.notfound p { color: var(--muted); margin-bottom: 24px; }

.btn {
  display: inline-block;
  padding: 8px 16px;
  border-radius: 8px;
  background: var(--accent);
  color: #202023;
  font-weight: 600;
  transition: transform 0.1s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }

/* ---------- Mobile ---------- */
@media (max-width: 520px) {
  .bio-item { flex-direction: column; gap: 2px; }
  .bio-year { min-width: 0; }
  .nav-link { padding: 6px 8px; font-size: 0.9rem; }
}