:root {
  --postech-red: #c21737;
  --postech-navy: #1e2a44;
  --postech-light: #f7f8fb;
  --postech-text: #1a1d24;
  --postech-muted: #5c6473;
  --border: #d9dde7;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Source Sans 3", "Noto Sans KR", "Apple SD Gothic Neo", sans-serif;
  color: var(--postech-text);
  background: linear-gradient(180deg, #ffffff 0%, #f8f9fd 100%);
  line-height: 1.6;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-top: 6px solid #8d1128;
  border-bottom: 1px solid #7c0f22;
  background: linear-gradient(90deg, #9d1730 0%, #c21737 100%);
}

.wrap {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 20px;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
}

.brand {
  color: #fff;
  font-weight: 700;
  text-decoration: none;
  letter-spacing: 0.3px;
}

.brand small {
  display: block;
  color: #f7d9e0;
  font-weight: 500;
  font-size: 0.8rem;
}

.nav {
  display: flex;
  gap: 16px;
}

.nav a {
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  opacity: 0.92;
}

.nav a:hover,
.nav a.active {
  color: #fff;
  opacity: 1;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.hero {
  padding: 54px 0 6px;
}

.hero-compact {
  padding-bottom: 20px;
}

.hero h1 {
  margin: 0;
  font-family: "Merriweather", Georgia, serif;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  color: var(--postech-navy);
  line-height: 1.2;
}

.hero p {
  max-width: 980px;
  font-size: 1.08rem;
  color: #303849;
}

.cta-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 16px;
}

.btn {
  display: inline-block;
  background: var(--postech-red);
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  padding: 10px 14px;
  border-radius: 8px;
  border: 1px solid #a50f2d;
}

.btn-secondary {
  background: #fff;
  color: var(--postech-navy);
  border-color: var(--border);
}

.card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
  margin: 18px 0;
  box-shadow: 0 8px 28px rgba(26, 33, 52, 0.05);
}

.card h2,
.card h3 {
  margin-top: 0;
  color: var(--postech-navy);
  font-family: "Merriweather", Georgia, serif;
}

.tight {
  margin-bottom: 8px;
}

.subhead {
  margin-bottom: 8px;
}

.muted-line {
  margin-top: 4px;
  margin-bottom: 0;
}

.profile-grid {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 20px;
  align-items: start;
}

.profile-photo {
  width: 100%;
  border-radius: 10px;
  border: 1px solid var(--border);
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.info-item {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px;
  background: #fbfcff;
}

.info-item strong {
  display: block;
  color: var(--postech-navy);
}

.divider {
  border: 0;
  border-top: 1px solid var(--border);
  margin: 22px 0;
}

.note {
  border-left: 4px solid var(--postech-red);
  padding: 10px 14px;
  background: var(--postech-light);
}

a {
  color: #9d1730;
}

a:hover {
  color: #7e0f24;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
}

th,
td {
  border: 1px solid var(--border);
  padding: 12px;
  text-align: left;
  vertical-align: top;
}

th {
  background: #f2f4fa;
  color: var(--postech-navy);
  font-weight: 700;
}

tbody tr:nth-child(even) {
  background: #fcfdff;
}

td strong {
  color: var(--postech-navy);
}

.download-list {
  margin: 0;
  padding-left: 18px;
}

.download-list li {
  margin: 8px 0;
}

.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 34px;
  padding: 20px 0 36px;
  color: var(--postech-muted);
  font-size: 0.95rem;
}

@media (max-width: 768px) {
  .header-inner {
    flex-direction: column;
    gap: 12px;
    align-items: flex-start;
  }

  .nav {
    flex-wrap: wrap;
  }

  .profile-grid,
  .info-grid {
    grid-template-columns: 1fr;
  }

  th,
  td {
    padding: 10px;
  }
}

.subsection-card {
  margin-top: 20px;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  background: #fcfdff;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.subsection-card h3 {
  margin-bottom: 10px;
}