:root {
  /* Professional Color Palette */
  --primary-blue: #2563eb;
  --primary-blue-dark: #1d4ed8;
  --primary-blue-light: #3b82f6;
  --accent-purple: #7c3aed;
  --accent-purple-dark: #6d28d9;
  
  /* Neutrals */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border-color: #e2e8f0;
  --border-color-light: #f1f5f9;
  
  /* Card Styles */
  --card-bg: #ffffff;
  --card-bg-hover: #fafbfc;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  /* Border Radius */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* Sidebar */
  --sidebar-width: 280px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
  line-height: 1.6;
  background: var(--bg-secondary);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Layout */
.resume-container {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background: var(--card-bg);
  border-right: 1px solid var(--border-color);
  padding: var(--spacing-2xl) var(--spacing-lg);
  position: fixed;
  height: 100vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
}

.sidebar-profile {
  text-align: center;
}

.profile-photo {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--border-color);
  margin-bottom: var(--spacing-md);
  transition: all 0.3s ease;
}

.profile-photo:hover {
  border-color: var(--primary-blue);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}

.profile-name {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
  letter-spacing: -0.02em;
}

.profile-title {
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* Navigation Links */
.nav-links {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.nav-link {
  padding: var(--spacing-sm) var(--spacing-md);
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.nav-link:hover {
  background: var(--bg-secondary);
  color: var(--primary-blue);
}

.nav-link.active {
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary-blue);
}

/* Social Links */
.social-links {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.social-link {
  padding: var(--spacing-sm) var(--spacing-md);
  text-decoration: none;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  justify-content: center;
}

.social-link:hover {
  border-color: var(--primary-blue);
  background: rgba(37, 99, 235, 0.05);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.social-link.linkedin { border-color: #0077b5; color: #0077b5; }
.social-link.github { border-color: #24292e; color: #24292e; }
.social-link.facebook { border-color: #4267B2; color: #4267B2; }
.social-link.email { border-color: var(--primary-blue); color: var(--primary-blue); }

.social-link.linkedin:hover { background: rgba(0, 119, 181, 0.05); }
.social-link.github:hover { background: rgba(36, 41, 46, 0.05); }
.social-link.facebook:hover { background: rgba(66, 103, 178, 0.05); }
.social-link.email:hover { background: rgba(37, 99, 235, 0.05); }

/* Donut Button */
.donut-btn {
  padding: var(--spacing-sm) var(--spacing-md);
  background: linear-gradient(135deg, #ff6b6b 0%, #ffa500 100%);
  color: white;
  text-decoration: none;
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 600;
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-md);
  border: none;
}

.donut-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* Main Content */
.main-content {
  margin-left: var(--sidebar-width);
  flex: 1;
  padding: var(--spacing-2xl);
  max-width: 900px;
}

/* Section */
.section {
  margin-bottom: var(--spacing-3xl);
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-lg);
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.section-title::before {
  content: '';
  width: 4px;
  height: 28px;
  background: var(--primary-blue);
  border-radius: 2px;
}

.section-description {
  font-size: 1.125rem;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
}

/* Cards */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  transition: all 0.3s ease;
  position: relative;
}

.card:hover {
  border-color: var(--primary-blue-light);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: start;
  margin-bottom: var(--spacing-md);
  gap: var(--spacing-md);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

.card-subtitle {
  font-size: 1rem;
  color: var(--primary-blue);
  font-weight: 500;
}

.card-meta {
  font-size: 0.875rem;
  color: var(--text-muted);
  text-align: right;
  white-space: nowrap;
}

.card-description {
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: var(--spacing-md);
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xs);
  margin-top: var(--spacing-md);
}

/* Skills & Tags */
.skill-tag {
  padding: 0.375rem 0.75rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-full);
  font-size: 0.8125rem;
  color: var(--text-secondary);
  font-weight: 500;
  transition: all 0.2s ease;
}

.skill-tag:hover {
  background: rgba(37, 99, 235, 0.1);
  border-color: var(--primary-blue);
  color: var(--primary-blue);
}

/* Skills Grid */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
}

.skill-category {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
}

.skill-category-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
}

.skill-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.skill-item {
  font-size: 0.875rem;
  color: var(--text-secondary);
  padding-left: var(--spacing-md);
  position: relative;
}

.skill-item::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--primary-blue);
  font-weight: 700;
}

/* Project Cards */
.project-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: var(--spacing-lg);
  transition: all 0.3s ease;
}

.project-card:hover {
  border-color: var(--primary-blue);
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.project-card-content {
  padding: var(--spacing-lg);
}

.project-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-bottom: 1px solid var(--border-color);
}

.project-actions {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}

/* Buttons */
.btn {
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.2s ease;
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  border: none;
  cursor: pointer;
}

.btn-primary {
  background: var(--primary-blue);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-blue-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.btn-secondary {
  background: transparent;
  color: var(--primary-blue);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: var(--bg-secondary);
  border-color: var(--primary-blue);
}

/* Read More Toggle */
.additional-content {
  display: none;
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--border-color);
}

.additional-content.show {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Education Card */
.education-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
}

.education-header {
  margin-bottom: var(--spacing-md);
}

.degree-title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

.university {
  font-size: 1rem;
  color: var(--primary-blue);
  font-weight: 500;
  margin-bottom: var(--spacing-xs);
}

.education-meta {
  font-size: 0.875rem;
  color: var(--text-muted);
}

.education-details {
  color: var(--text-secondary);
  line-height: 1.7;
}

.education-details ul {
  margin-left: var(--spacing-lg);
  margin-top: var(--spacing-sm);
}

.education-details li {
  margin-bottom: var(--spacing-xs);
}

/* Responsive Design */
@media (max-width: 1024px) {
  .sidebar {
    width: 240px;
  }
  
  --sidebar-width: 240px;
  
  .main-content {
    margin-left: 240px;
  }
}

@media (max-width: 768px) {
  .resume-container {
    flex-direction: column;
  }
  
  .sidebar {
    width: 100%;
    position: relative;
    height: auto;
    border-right: none;
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-lg);
  }
  
  .main-content {
    margin-left: 0;
    padding: var(--spacing-lg);
  }
  
  .profile-photo {
    width: 100px;
    height: 100px;
  }
  
  .profile-name {
    font-size: 1.25rem;
  }
  
  .nav-links,
  .social-links {
    flex-direction: row;
    flex-wrap: wrap;
  }
  
  .section-title {
    font-size: 1.5rem;
  }
  
  .card-header {
    flex-direction: column;
  }
  
  .card-meta {
    text-align: left;
  }
  
  .skills-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .main-content {
    padding: var(--spacing-md);
  }
  
  .section {
    margin-bottom: var(--spacing-xl);
  }
  
  .card {
    padding: var(--spacing-md);
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}