:root {
  --bg: #f7f8fb;
  --surface: #ffffff;
  --surface-muted: #eef2f7;
  --text: #172033;
  --text-muted: #657084;
  --primary: #2563eb;
  --primary-dark: #1e40af;
  --line: #d9e1ee;
  --shadow: 0 18px 45px rgba(23, 32, 51, 0.08);
  --radius-lg: 28px;
  --radius-md: 18px;
  --container: 1120px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Pretendard", "Noto Sans KR", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
}

a {
  color: inherit;
  text-decoration: none;
}

ul {
  margin: 0;
  padding-left: 1.1rem;
}

li + li {
  margin-top: 0.35rem;
}

.container {
  width: min(var(--container), calc(100% - 40px));
  margin: 0 auto;
}

.section {
  padding: 96px 0;
}

.section-muted {
  background: var(--surface-muted);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(18px);
  background: rgba(247, 248, 251, 0.82);
  border-bottom: 1px solid rgba(217, 225, 238, 0.75);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
}

.logo {
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--primary-dark);
}

.nav {
  display: flex;
  gap: 22px;
  font-size: 0.94rem;
  color: var(--text-muted);
}

.nav a {
  transition: color 0.2s ease;
}

.nav a:hover {
  color: var(--primary);
}

.hero {
  min-height: calc(100vh - 72px);
  display: flex;
  align-items: center;
  background:
    radial-gradient(circle at top left, rgba(37, 99, 235, 0.16), transparent 34%),
    linear-gradient(135deg, #f7f8fb 0%, #edf3ff 100%);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(320px, 0.65fr);
  gap: 48px;
  align-items: center;
}

.eyebrow,
.section-label,
.project-meta,
.timeline-date {
  color: var(--primary);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero h1 {
  margin: 14px 0 24px;
  font-size: clamp(2.4rem, 5vw, 4.6rem);
  line-height: 1.13;
  letter-spacing: -0.065em;
}

.hero h1 span {
  color: var(--primary);
}

.hero-description {
  max-width: 720px;
  color: var(--text-muted);
  font-size: 1.08rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 22px;
  border-radius: 999px;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn.primary {
  background: var(--primary);
  color: white;
  box-shadow: 0 12px 28px rgba(37, 99, 235, 0.28);
}

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

.btn.secondary {
  background: white;
  color: var(--text);
  border: 1px solid var(--line);
}

.hero-card,
.card,
.project-card,
.contact-card {
  background: rgba(255, 255, 255, 0.88);
  border: 1px solid rgba(217, 225, 238, 0.88);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
}

.hero-card {
  padding: 30px;
}

.hero-card h2 {
  margin: 0 0 20px;
  font-size: 1.15rem;
}

.keyword-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.keyword-list span {
  padding: 8px 12px;
  border-radius: 999px;
  background: #edf3ff;
  color: var(--primary-dark);
  font-size: 0.9rem;
  font-weight: 700;
}

.split-layout {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 60px;
}

.section h2,
.section-heading h2,
.contact-card h2 {
  margin: 10px 0 18px;
  font-size: clamp(1.9rem, 3vw, 3rem);
  line-height: 1.25;
  letter-spacing: -0.045em;
}

.section-text,
.section-heading p,
.contact-card p,
.project-card p,
.trouble-card p,
.timeline-item p {
  color: var(--text-muted);
}

.section-text p:first-child {
  margin-top: 0;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 40px;
}

.skill-grid,
.trouble-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 20px;
}

.card {
  padding: 26px;
  border-radius: var(--radius-md);
}

.skill-card h3,
.trouble-card h3,
.timeline-item h3 {
  margin: 0 0 14px;
  font-size: 1.18rem;
  letter-spacing: -0.02em;
}

.skill-card ul {
  color: var(--text-muted);
  font-size: 0.96rem;
}

.project-list {
  display: grid;
  gap: 24px;
}

.project-card {
  padding: 34px;
}

.project-card h3 {
  margin: 8px 0 12px;
  font-size: 1.55rem;
  letter-spacing: -0.035em;
}

.project-detail-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 24px;
}

.project-detail-grid div {
  padding: 16px;
  border-radius: 16px;
  background: #f7f9fc;
  border: 1px solid var(--line);
}

.project-detail-grid strong {
  display: block;
  margin-bottom: 6px;
  color: var(--text);
}

.project-detail-grid span {
  display: block;
  color: var(--text-muted);
  font-size: 0.93rem;
}

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

.timeline {
  border-left: 2px solid var(--line);
  padding-left: 28px;
}

.timeline-item {
  position: relative;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -36px;
  top: 8px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 0 0 6px #dbeafe;
}

.contact-section {
  padding-top: 40px;
}

.contact-card {
  padding: 48px;
  text-align: center;
  background:
    radial-gradient(circle at top right, rgba(37, 99, 235, 0.14), transparent 32%),
    #ffffff;
}

.contact-card p {
  max-width: 720px;
  margin-left: auto;
  margin-right: auto;
}

.contact-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.contact-links a {
  padding: 10px 16px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #f7f9fc;
  font-weight: 700;
  color: var(--primary-dark);
}

.site-footer {
  padding: 28px 0;
  border-top: 1px solid var(--line);
  color: var(--text-muted);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  font-size: 0.92rem;
}

.footer-inner p {
  margin: 0;
}

.footer-inner a {
  font-weight: 700;
  color: var(--primary-dark);
}

@media (max-width: 980px) {
  .hero-grid,
  .split-layout {
    grid-template-columns: 1fr;
  }

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

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

@media (max-width: 760px) {
  .container {
    width: min(100% - 28px, var(--container));
  }

  .section {
    padding: 72px 0;
  }

  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
    padding: 16px 0;
  }

  .nav {
    width: 100%;
    overflow-x: auto;
    gap: 16px;
    padding-bottom: 4px;
    white-space: nowrap;
  }

  .hero {
    min-height: auto;
    padding-top: 54px;
  }

  .hero-card,
  .project-card,
  .contact-card {
    padding: 24px;
  }

  .skill-grid,
  .trouble-grid,
  .project-detail-grid {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}