/* Header */
header {
  background-color: var(--header-bg);
  border-bottom: 1px solid var(--border-color);
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
  transition: background-color 0.3s, border-color 0.3s;
}

header h1 {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}

header h1 a {
  color: inherit;
  text-decoration: none;
}

.nav-container {
  display: flex;
  align-items: center;
  gap: 1.2rem;
}

header nav a {
  font-size: 0.875rem;
  color: var(--text-sub);
}

/* Layout Container */
main {
  flex: 1;
  max-width: 850px;
  width: 100%;
  margin: 0 auto;
  padding: 2.5rem 1rem;
}

/* Footer & Modal */
footer {
  background-color: var(--footer-bg);
  border-top: 1px solid var(--border-color);
  padding: 2rem 1rem;
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-sub);
  transition: background-color 0.3s, border-color 0.3s;
}

.footer-links {
  margin-bottom: 1rem;
}

.footer-links a {
  margin: 0 0.5rem;
  color: var(--text-sub);
}

.modal {
  display: none;
  position: fixed;
  top: 0; left: 0; width: 100%; height: 100%;
  background: rgba(0,0,0,0.7);
  justify-content: center;
  align-items: center;
  z-index: 1000;
}

.modal-content {
  background: var(--card-bg);
  padding: 2rem;
  border-radius: 8px;
  max-width: 600px;
  width: 90%;
  max-height: 80vh;
  overflow-y: auto;
  color: var(--text-sub);
  font-size: 0.9rem;
}

.modal-close {
  float: right;
  cursor: pointer;
  color: var(--text-main);
  font-weight: bold;
}