:root {
  --bg-dark: #0a0a0a;
  --text-primary: #f0f0f0;
  --text-secondary: #b5b5b5;
  --accent: #ffffff;
  --border: #2a2a2a;
}

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

body {
  background: var(--bg-dark);
  color: var(--text-primary);
  font-family: 'Courier New', Courier, monospace;
  line-height: 1.75;
  padding: 2rem;
  max-width: 1200px;
  margin: 0 auto;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Navigation - Centered */
nav {
  margin-bottom: 4rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border);
  text-align: center;
}

nav ul {
  list-style: none;
  display: inline-flex;
  gap: 2.5rem;
  flex-wrap: wrap;
  justify-content: center;
}

nav a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
  font-size: 0.95rem;
}

nav a:hover,
nav a.active {
  color: var(--accent);
}

/* Typography */
h1 {
  font-size: 2.25rem;
  font-weight: 700;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
  color: var(--accent);
  line-height: 1.3;
}

h2 {
  font-size: 1.4rem;
  font-weight: 600;
  margin: 1.5rem 0 1rem;
  color: var(--text-primary);
  line-height: 1.4;
}

h3 {
  font-size: 1.15rem;
  font-weight: 500;
  margin: 1rem 0 0.5rem;
  color: var(--text-secondary);
}

p {
  margin-bottom: 1.25rem;
  color: var(--text-secondary);
  line-height: 1.75;
  font-size: 1rem;
  text-align: justify;
}

/* Links */
a {
  color: var(--text-primary);
  text-decoration: none;
  transition: all 0.2s ease;
  border-bottom: 1px solid transparent;
}

a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* Lists */
ul {
  list-style: none;
  padding-left: 0;
}

li {
  margin-bottom: 0.5rem;
  padding-left: 1.5rem;
  color: var(--text-secondary);
  line-height: 1.75;
  font-size: 1rem;
  text-align: justify;
}

li::before {
  content: "→ ";
  margin-left: -1.5rem;
  color: var(--text-primary);
  font-weight: bold;
}

/* Content sections */
.content {
  margin-top: 3rem;
}

.item {
  margin-bottom: 2.5rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid var(--border);
}

.item:last-child {
  border-bottom: none;
}

.item-title {
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  font-weight: 600;
  font-size: 1.05rem;
  line-height: 1.5;
}

.item-meta {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 0.75rem;
  line-height: 1.6;
}

/* Centered Home Page */
.centered-page {
  text-align: center;
}

.centered-page h1,
.centered-page h2,
.centered-page h3 {
  text-align: center;
}

.centered-page > p {
  text-align: justify;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.centered-page > ul {
  text-align: left;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  display: inline-block;
}

/* Green Terminal Highlight */
.highlight {
  color: #00ff00;
  font-weight: 700;
  text-shadow: 0 0 8px rgba(0, 255, 0, 0.5);
}

/* Course components */
.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.course-card {
  padding: 1.75rem;
  border: 1px solid var(--border);
  text-decoration: none;
  color: inherit;
  transition: all 0.2s ease;
  display: block;
}

.course-card:hover {
  border-color: var(--text-primary);
  background: rgba(255, 255, 255, 0.02);
}

.course-card h2 {
  margin: 0 0 0.75rem 0;
  font-size: 1.3rem;
  color: var(--text-primary);
}

.course-card p {
  margin-top: 1rem;
  font-size: 0.95rem;
  line-height: 1.65;
}

.course-code {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin: 0.5rem 0;
}

.course-semester {
  color: var(--text-secondary);
  font-size: 0.825rem;
}

.course-meta {
  display: flex;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--text-secondary);
}

.course-section {
  margin: 2.5rem 0;
}

.course-section h2 {
  margin-bottom: 1.5rem;
}

.course-section ul li {
  margin-bottom: 0.5rem;
  padding-left: 0;
}

.course-section ul li::before {
  display: none;
}

.course-section ul li a {
  color: var(--text-primary);
  padding: 0.5rem 0;
  display: inline-block;
}

.back-link {
  display: inline-block;
  margin-bottom: 1.5rem;
  color: var(--text-secondary);
  border-bottom: 1px solid transparent;
}

.back-link:hover {
  color: var(--text-primary);
  border-bottom-color: var(--text-primary);
}

/* Lab attachments */
.lab-item {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.lab-attachments {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
  margin-top: 0.5rem;
  padding-left: 1.5rem;
}

.attachments-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-right: 0.5rem;
}

.attachment-link {
  font-size: 0.875rem;
  color: var(--text-secondary);
  padding: 0.4rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.attachment-link:hover {
  color: var(--text-primary);
  border-color: var(--text-primary);
  background: rgba(255, 255, 255, 0.02);
}

/* Mobile optimizations */
@media (max-width: 768px) {
  body {
    padding: 1.5rem;
  }

  .courses-grid {
    grid-template-columns: 1fr;
  }
  
  nav ul {
    gap: 1.5rem;
  }
}

@media (max-width: 480px) {
  body {
    padding: 1rem;
  }
}


.profile-placeholder {
  margin: 0 auto 2rem;
  width: 150px;
  height: 150px;
  border-radius: 50%;
  background: #000000;
  border: 2px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  font-weight: 700;
  color: #00ff00;
  transition: all 0.3s ease;
}

.profile-placeholder::before {
  content: "IT";
}

.profile-placeholder:hover {
  border-color: #00ff00;
  box-shadow: 0 0 20px rgba(0, 255, 0, 0.3);
}

footer {
  margin-top: 5rem;
  padding: 2rem 0;
  border-top: 1px solid var(--border);
  text-align: center;
}

footer a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  transition: all 0.2s ease;
  display: inline-block;
}

footer a::before {
  content: "✉ ";
  margin-right: 0.5rem;
  color: #00ff00;
}

footer a:hover {
  color: #00ff00;
  transform: translateY(-2px);
}