/* CSS Custom Properties */
:root {
  /* Colors */
  --primary-color: #3b82f6;
  --primary-dark: #2563eb;
  --secondary-color: #8b5cf6;
  --accent-color: #06b6d4;
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --danger-color: #ef4444;

  /* Text Colors */
  --text-primary: #1f2937;
  --text-secondary: #6b7280;
  --text-muted: #9ca3af;

  /* Background Colors */
  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-tertiary: #f3f4f6;
  --bg-card: #ffffff;

  /* Dark Theme Colors */
  --dark-bg-primary: #0f172a;
  --dark-bg-secondary: #1e293b;
  --dark-bg-tertiary: #334155;
  --dark-bg-card: #1e293b;
  --dark-text-primary: #f1f5f9;
  --dark-text-secondary: #cbd5e1;
  --dark-text-muted: #94a3b8;

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;

  /* Typography */
  --font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;

  /* Border Radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1),
    0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1),
    0 8px 10px -6px rgb(0 0 0 / 0.1);

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 200ms ease-in-out;
  --transition-slow: 300ms ease-in-out;
}

/* Dark Theme */
[data-theme="dark"] {
  --bg-primary: var(--dark-bg-primary);
  --bg-secondary: var(--dark-bg-secondary);
  --bg-tertiary: var(--dark-bg-tertiary);
  --bg-card: var(--dark-bg-card);
  --text-primary: var(--dark-text-primary);
  --text-secondary: var(--dark-text-secondary);
  --text-muted: var(--dark-text-muted);
}

/* Reset & Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  transition: background-color var(--transition-normal),
    color var(--transition-normal);
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
}

h1 {
  font-size: var(--font-size-4xl);
}
h2 {
  font-size: var(--font-size-3xl);
}
h3 {
  font-size: var(--font-size-2xl);
}
h4 {
  font-size: var(--font-size-xl);
}

p {
  margin-bottom: var(--spacing-md);
  color: var(--text-secondary);
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--primary-dark);
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
  z-index: 1000;
  transition: all var(--transition-normal);
}

[data-theme="dark"] .navbar {
  background: rgba(15, 23, 42, 0.95);
  border-bottom-color: rgba(255, 255, 255, 0.1);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md) var(--spacing-lg);
  max-width: 1200px;
  margin: 0 auto;
}

.nav-brand {
  display: flex;
  align-items: center;
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--text-primary);
}

.nav-brand i {
  margin-right: var(--spacing-sm);
  color: var(--primary-color);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
}

.nav-link {
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

.nav-link:hover {
  color: var(--primary-color);
}

.theme-toggle {
  background: none;
  border: 2px solid var(--text-muted);
  border-radius: var(--radius-md);
  padding: var(--spacing-sm);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.theme-toggle:hover {
  border-color: var(--primary-color);
  color: var(--primary-color);
}

.hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
}

.hamburger span {
  width: 25px;
  height: 3px;
  background: var(--text-primary);
  margin: 3px 0;
  transition: var(--transition-fast);
}

/* Hero Section */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: linear-gradient(
    135deg,
    var(--bg-primary) 0%,
    var(--bg-secondary) 100%
  );
  padding-top: 80px;
}

.hero-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-3xl);
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.hero-title {
  font-size: var(--font-size-5xl);
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
  line-height: 1.1;
}

.gradient-text {
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: var(--font-size-xl);
  color: var(--text-secondary);
  margin-bottom: var(--spacing-2xl);
}

.hero-actions {
  display: flex;
  gap: var(--spacing-lg);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  border: none;
  border-radius: var(--radius-lg);
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
}

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

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

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 2px solid var(--text-muted);
}

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

/* Code Window */
.code-window {
  background: var(--dark-bg-secondary);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  transform: perspective(1000px) rotateY(-5deg) rotateX(5deg);
  transition: transform var(--transition-slow);
}

.code-window:hover {
  transform: perspective(1000px) rotateY(0deg) rotateX(0deg);
}

.window-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md);
  background: var(--dark-bg-tertiary);
}

.dots {
  display: flex;
  gap: var(--spacing-sm);
}

.dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.dot.red {
  background: #ef4444;
}
.dot.yellow {
  background: #f59e0b;
}
.dot.green {
  background: #10b981;
}

.window-title {
  color: var(--dark-text-secondary);
  font-size: var(--font-size-sm);
}

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

.code-content pre {
  color: var(--dark-text-primary);
  font-family: "Monaco", "Menlo", monospace;
  font-size: var(--font-size-sm);
  line-height: 1.6;
}

/* Progress Overview */
.progress-overview {
  padding: var(--spacing-3xl) 0;
  background: var(--bg-secondary);
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
}

.progress-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-xl);
}

.stat-card {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  background: var(--bg-card);
  padding: var(--spacing-xl);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.stat-icon {
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  border-radius: var(--radius-lg);
  color: white;
  font-size: var(--font-size-xl);
}

.stat-content h3 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
}

.stat-content p {
  color: var(--text-muted);
  margin: 0;
}

/* Phases Section */
.phases-section {
  padding: var(--spacing-3xl) 0;
}

.phases-container {
  display: grid;
  gap: var(--spacing-xl);
}

.phase-card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-sm);
  border-left: 4px solid var(--primary-color);
  transition: all var(--transition-normal);
}

.phase-card:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-md);
}

.phase-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--spacing-lg);
  cursor: pointer;
}

.phase-title {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.phase-number {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  font-weight: 700;
}

.phase-toggle {
  background: none;
  border: none;
  font-size: var(--font-size-lg);
  color: var(--text-muted);
  cursor: pointer;
  transition: transform var(--transition-fast);
}

.phase-toggle.active {
  transform: rotate(180deg);
}

.phase-content {
  display: none;
  animation: fadeIn var(--transition-normal);
}

.phase-content.active {
  display: block;
}

.subsection {
  margin-bottom: var(--spacing-xl);
}

.subsection h4 {
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.practice-list,
.theory-list {
  list-style: none;
  margin-left: var(--spacing-lg);
}

.practice-list li,
.theory-list li {
  position: relative;
  padding: var(--spacing-sm) 0;
  color: var(--text-secondary);
}

.practice-list li::before {
  content: "🛠️";
  position: absolute;
  left: -25px;
}

.theory-list li::before {
  content: "📚";
  position: absolute;
  left: -25px;
}

/* Comparison Section */
.comparison-section {
  padding: var(--spacing-3xl) 0;
  background: var(--bg-secondary);
}

.comparison-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-2xl);
}

.comparison-card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
}

.comparison-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.card-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.card-header i {
  font-size: var(--font-size-2xl);
  color: var(--primary-color);
}

.comparison-list {
  list-style: none;
}

.comparison-list li {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-sm) 0;
  color: var(--text-secondary);
}

.comparison-list i {
  color: var(--success-color);
}

/* Projects Section */
.projects-section {
  padding: var(--spacing-3xl) 0;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: var(--spacing-xl);
}

.project-card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-normal);
  border: 1px solid transparent;
}

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

.project-icon {
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(
    135deg,
    var(--primary-color),
    var(--secondary-color)
  );
  border-radius: var(--radius-lg);
  color: white;
  font-size: var(--font-size-xl);
  margin-bottom: var(--spacing-lg);
}

.project-tech {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-lg);
}

.tech-tag {
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-xs);
  font-weight: 500;
}

/* Modal */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  z-index: 2000;
  animation: fadeIn var(--transition-normal);
}

.modal.active {
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-content {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  max-width: 600px;
  width: 90%;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  animation: slideIn var(--transition-normal);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-xl);
  border-bottom: 1px solid var(--bg-tertiary);
}

.modal-close {
  background: none;
  border: none;
  font-size: var(--font-size-xl);
  color: var(--text-muted);
  cursor: pointer;
  padding: var(--spacing-sm);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.modal-close:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.modal-body {
  padding: var(--spacing-xl);
}

.progress-summary {
  margin-bottom: var(--spacing-xl);
  text-align: center;
}

.progress-percentage {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.progress-percentage span {
  font-size: var(--font-size-3xl);
}

.progress-bar {
  height: 10px;
  background-color: var(--bg-tertiary);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: var(--spacing-lg);
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  border-radius: var(--radius-lg);
  width: 0%;
  transition: width var(--transition-normal);
}

.progress-tracker {
  display: grid;
  gap: var(--spacing-md);
}

.progress-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
}

.progress-item:hover {
  background: var(--bg-tertiary);
}

.progress-checkbox {
  width: 20px;
  height: 20px;
  border: 2px solid var(--text-muted);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.progress-checkbox.checked {
  background: var(--success-color);
  border-color: var(--success-color);
  color: white;
}

.progress-label {
  flex: 1;
  color: var(--text-secondary);
  font-weight: 500;
}

.progress-label.completed {
  text-decoration: line-through;
  color: var(--text-muted);
}

/* Footer */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--bg-tertiary);
  padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
}

.footer-section h3,
.footer-section h4 {
  color: var(--text-primary);
  margin-bottom: var(--spacing-lg);
}

.footer-section ul {
  list-style: none;
}

.footer-section ul li {
  margin-bottom: var(--spacing-sm);
}

.footer-section ul li a {
  color: var(--text-secondary);
  transition: color var(--transition-fast);
}

.footer-section ul li a:hover {
  color: var(--primary-color);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-xl);
  border-top: 1px solid var(--bg-tertiary);
  color: var(--text-muted);
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Responsive Design */
@media (max-width: 1024px) {
  .hero-container {
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
    text-align: center;
  }

  .comparison-grid {
    grid-template-columns: 1fr;
  }

  .code-window {
    transform: none;
  }
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }

  .hamburger {
    display: flex;
  }

  .hero-title {
    font-size: var(--font-size-3xl);
  }

  .hero-subtitle {
    font-size: var(--font-size-lg);
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }

  .progress-stats {
    grid-template-columns: 1fr;
  }

  .projects-grid {
    grid-template-columns: 1fr;
  }

  .modal-content {
    width: 95%;
    margin: var(--spacing-lg);
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--spacing-md);
  }

  .nav-container {
    padding: var(--spacing-md);
  }

  .hero-container {
    padding: 0 var(--spacing-md);
  }

  .section-title {
    font-size: var(--font-size-2xl);
  }

  .stat-card {
    flex-direction: column;
    text-align: center;
  }

  .footer-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
  }
}

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

/* Focus States */
button:focus,
input:focus,
select:focus,
textarea:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
  :root {
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.3),
      0 2px 4px -2px rgb(0 0 0 / 0.3);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.3),
      0 4px 6px -4px rgb(0 0 0 / 0.3);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.3),
      0 8px 10px -6px rgb(0 0 0 / 0.3);
  }
}

/* Print Styles */
@media print {
  .navbar,
  .hero-actions,
  .theme-toggle,
  .modal,
  .footer {
    display: none !important;
  }

  .hero {
    min-height: auto;
    padding: var(--spacing-lg) 0;
  }

  .phase-content {
    display: block !important;
  }

  body {
    font-size: 12pt;
    line-height: 1.4;
    color: black;
    background: white;
  }

  .section-title {
    page-break-after: avoid;
  }

  .phase-card {
    page-break-inside: avoid;
    border: 1px solid #ccc;
    margin-bottom: 1rem;
  }
}