body {
  margin: 0;
  font-family: "Noto Sans KR", "Malgun Gothic", Arial, sans-serif;
  background: #f5f7fb;
  color: #1f2937;
  line-height: 1.7;
  word-break: keep-all;
  overflow-wrap: break-word;
}

header {
  background: linear-gradient(135deg, #1d4ed8, #7c3aed);
  color: white;
  padding: 80px 24px;
  text-align: center;
}

header h1 {
  font-size: 46px;
  margin: 0 0 16px;
  font-weight: 800;
}

header p {
  font-size: 22px;
  margin: 0;
}

nav {
  background: white;
  padding: 18px;
  text-align: center;
  box-shadow: 0 2px 10px rgba(0,0,0,0.08);
  position: sticky;
  top: 0;
  z-index: 10;
}

nav a {
  margin: 0 14px;
  text-decoration: none;
  color: #1d4ed8;
  font-weight: 700;
}

section {
  max-width: 1100px;
  margin: 40px auto;
  background: white;
  padding: 40px;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.08);
}

h2 {
  font-size: 30px;
  color: #111827;
  border-left: 8px solid #2563eb;
  padding-left: 14px;
  margin-top: 0;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.card {
  background: #f9fafb;
  padding: 24px;
  border-radius: 16px;
  border: 1px solid #e5e7eb;
}

.card h3 {
  margin-top: 0;
  color: #1d4ed8;
}

.highlight {
  font-size: 20px;
  font-weight: 700;
  color: #111827;
  background: #eef2ff;
  padding: 20px;
  border-radius: 16px;
}

.profile-image,
.banner-image,
.lecture-image {
  width: 100%;
  max-width: 760px;
  border-radius: 20px;
  display: block;
  margin: 24px auto;
  box-shadow: 0 10px 30px rgba(0,0,0,0.12);
}

footer {
  text-align: center;
  padding: 40px 20px;
  background: #111827;
  color: white;
  margin-top: 60px;
}

.button {
  display: inline-block;
  background: #2563eb;
  color: white;
  padding: 14px 24px;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 700;
  margin-top: 16px;
}