:root {
  --bg-color: #f8f9fa;
  --text-color: #212529;
  --accent-color: #007aff;
  --glass-bg: rgba(255, 255, 255, 0.8);
  --glass-border: rgba(0, 0, 0, 0.1);
  --card-bg: #ffffff;
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: var(--font-family);
  line-height: 1.6;
  overflow-x: hidden;
}

/* Glassmorphism Header */
header {
  position: fixed;
  top: 0;
  width: 100%;
  padding: 1rem 2rem;
  background: var(--glass-bg);
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  border-bottom: 1px solid var(--glass-border);
  z-index: 1000;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo-container {
  display: flex;
  align-items: center;
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 1rem;
  text-decoration: none;
  transition: opacity 0.3s ease;
}

.logo-link:hover {
  opacity: 0.8;
}

.logo {
  height: 40px;
  width: auto;
  object-fit: contain;
}

.logo-divider {
  width: 1px;
  height: 25px;
  background-color: var(--glass-border);
  display: inline-block;
}

nav ul {
  display: flex;
  list-style: none;
  gap: 2rem;
}

nav a {
  color: var(--text-color);
  text-decoration: none;
  font-weight: 500;
  opacity: 0.7;
  transition: opacity 0.3s, color 0.3s;
  cursor: pointer;
}

nav a.active {
  opacity: 1;
  color: var(--accent-color);
}

nav a:hover {
  opacity: 1;
}

/* Main Content */
main {
  margin-top: 80px;
  min-height: calc(100vh - 80px);
}

.section {
  display: none !important;
  padding: 2rem;
  max-width: 1200px;
  margin: 0 auto;
  animation: fadeIn 0.5s ease-out;
}

.section.active {
  display: block !important;
}

#architecture-map-section.active {
  display: block !important;
  max-width: none;
  padding: 0;
  width: 100%;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Markdown Styling */
.markdown-container {
  background: var(--card-bg);
  padding: 3rem;
  border-radius: 12px;
  border: 1px solid var(--glass-border);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
  /* Softer shadow for light mode */
}

.markdown-container h1 {
  font-size: 2.5rem;
  margin-bottom: 2rem;
  color: #1a1a1a;
}

.markdown-container h2 {
  font-size: 1.8rem;
  margin: 2.5rem 0 1rem;
  border-bottom: 1px solid var(--glass-border);
  padding-bottom: 0.5rem;
}

.markdown-container h3 {
  font-size: 1.4rem;
  margin: 1.5rem 0 1rem;
  color: var(--accent-color);
}

.markdown-container p {
  margin-bottom: 1.5rem;
}

.markdown-container ul,
.markdown-container ol {
  margin-left: 2rem;
  margin-bottom: 1.5rem;
}

.markdown-container code {
  background: rgba(0, 0, 0, 0.05);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  font-family: monospace;
}

/* Markmap Styling */
#markmap-container {
  height: calc(100vh - 80px);
  /* Fill remaining viewport height */
  width: 100%;
  background: var(--card-bg);
  border-radius: 0;
  border: none;
  overflow: hidden;
  position: relative;
}

#markmap-container svg {
  width: 100%;
  height: 100%;
}

/* Utility */
.loading {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 400px;
  font-size: 1.2rem;
  opacity: 0.5;
}