:root {
  --bg: #f3f6fb;
  --surface: #ffffff;
  --text: #121826;
  --muted: #4c5a73;
  --line: #d8e1ef;
  --accent: #0f6fff;
  --accent-strong: #004ec2;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  font-family: "IBM Plex Sans KR", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 15% 5%, #dce9ff 0%, transparent 35%),
    radial-gradient(circle at 90% 10%, #e7f4ff 0%, transparent 30%),
    var(--bg);
  scroll-behavior: smooth;
}

.container {
  width: min(980px, 92%);
  margin: 0 auto;
}

.topbar {
  position: sticky;
  top: 0;
  backdrop-filter: blur(8px);
  background: rgba(243, 246, 251, 0.8);
  border-bottom: 1px solid var(--line);
  z-index: 20;
}

.nav {
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  color: var(--text);
  font-weight: 700;
  text-decoration: none;
  letter-spacing: 0.4px;
}

.menu-button {
  display: none;
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 8px;
  padding: 6px 10px;
}

.menu-list {
  list-style: none;
  display: flex;
  gap: 20px;
  margin: 0;
  padding: 0;
}

.menu-list a {
  color: var(--muted);
  text-decoration: none;
  font-weight: 600;
  font-size: 14px;
}

.menu-list a:hover {
  color: var(--accent);
}

.section {
  padding: 76px 0;
}

.hero {
  min-height: 70vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero-sub {
  color: var(--accent);
  margin: 0 0 12px;
  font-family: "JetBrains Mono", monospace;
}

h1 {
  margin: 0;
  font-size: clamp(38px, 7vw, 68px);
  line-height: 1.08;
}

.hero-desc {
  margin-top: 18px;
  max-width: 700px;
  color: var(--muted);
  line-height: 1.65;
}

.hero-actions {
  margin-top: 28px;
  display: flex;
  gap: 12px;
}

.metrics {
  padding-top: 10px;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.metric-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
}

.metric-value {
  margin: 0 0 4px;
  font-family: "JetBrains Mono", monospace;
  font-size: 24px;
  font-weight: 600;
  color: var(--accent-strong);
}

.metric-label {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
}

.btn {
  text-decoration: none;
  padding: 11px 18px;
  border-radius: 10px;
  border: 1px solid transparent;
  font-weight: 600;
}

.btn.primary {
  background: var(--accent);
  color: white;
}

.btn.primary:hover {
  background: var(--accent-strong);
}

.btn.ghost {
  border-color: var(--line);
  color: var(--text);
  background: var(--surface);
}

.btn.ghost:hover {
  border-color: #adc4ea;
}

h2 {
  margin: 0 0 18px;
  font-size: 30px;
}

h3 {
  margin: 0 0 8px;
}

p {
  margin: 0 0 12px;
  line-height: 1.7;
}

.alt {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.7), rgba(255, 255, 255, 0.94));
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.timeline-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px;
  margin-bottom: 14px;
}

.period {
  color: var(--muted);
  font-family: "JetBrains Mono", monospace;
  font-size: 13px;
  margin-bottom: 10px;
}

ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
}

.skill-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.skill-grid > div {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 18px;
}

.skill-grid p {
  color: var(--muted);
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px;
}

.card p {
  color: var(--muted);
}

.card ul {
  margin-top: 12px;
}

.card-link {
  display: inline-block;
  margin-top: 14px;
  text-decoration: none;
  font-weight: 600;
  color: var(--accent);
}

.card-link:hover {
  text-decoration: underline;
}

.contact {
  text-align: center;
}

.mail {
  display: inline-block;
  margin-top: 6px;
  color: var(--accent);
  font-family: "JetBrains Mono", monospace;
  text-decoration: none;
}

.mail:hover {
  text-decoration: underline;
}

.footer {
  border-top: 1px solid var(--line);
  padding: 24px 0 34px;
  color: var(--muted);
  font-size: 14px;
  text-align: center;
}

.detail-page {
  min-height: calc(100vh - 140px);
}

.detail-head {
  margin-bottom: 20px;
}

.detail-head h1 {
  margin: 0 0 8px;
  font-size: clamp(28px, 5vw, 42px);
}

.detail-meta {
  color: var(--muted);
  font-family: "JetBrains Mono", monospace;
  font-size: 13px;
}

.detail-box {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px;
  margin-bottom: 14px;
}

.detail-box h2 {
  margin: 0 0 10px;
  font-size: 20px;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 8px;
}

.tag {
  border: 1px solid #b8cbeb;
  background: #eaf1ff;
  color: #174491;
  border-radius: 999px;
  font-size: 12px;
  padding: 4px 9px;
}

@media (max-width: 900px) {
  .project-grid {
    grid-template-columns: 1fr;
  }

  .skill-grid {
    grid-template-columns: 1fr;
  }

  .metric-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .menu-button {
    display: block;
  }

  .menu-list {
    position: absolute;
    right: 4%;
    top: 58px;
    width: 210px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 12px;
    display: none;
    flex-direction: column;
    gap: 10px;
  }

  .menu-list.open {
    display: flex;
  }
}