/* Global Styles */
:root {
  --primary-color: #2563eb;
  --secondary-color: #64748b;
  --accent-color: #f59e0b;
  --success-color: #10b981;
  --danger-color: #ef4444;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --bg-light: #f8fafc;
  --bg-white: #ffffff;
  --border-color: #e2e8f0;
  
  /* Dark mode variables */
  --dark-bg: #0f172a;
  --dark-bg-light: #1e293b;
  --dark-text-primary: #f1f5f9;
  --dark-text-secondary: #94a3b8;
  --dark-border: #334155;
  
  /* Animation variables */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* Dark mode styles */
[data-theme="dark"] {
  --text-primary: var(--dark-text-primary);
  --text-secondary: var(--dark-text-secondary);
  --bg-light: var(--dark-bg-light);
  --bg-white: var(--dark-bg);
  --border-color: var(--dark-border);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-white);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

main {
  flex: 1 0 auto;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: 1rem;
}

.display-1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.display-2 {
  font-size: clamp(2rem, 4vw, 2.5rem);
  font-weight: 600;
}

.lead {
  font-size: clamp(1.1rem, 2vw, 1.25rem);
  font-weight: 400;
  color: var(--text-secondary);
}

/* Sections */
section {
  padding: clamp(3rem, 8vw, 5rem) 0;
  opacity: 0;
  transform: translateY(30px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

section.visible {
  opacity: 1;
  transform: translateY(0);
}

.section-title {
  font-size: clamp(2rem, 4vw, 2.5rem);
  font-weight: 700;
  margin-bottom: clamp(2rem, 5vw, 3rem);
  text-align: center;
  position: relative;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
  border-radius: 2px;
}

/* Theme Toggle */
.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 1000;
  background: var(--bg-white);
  border: 2px solid var(--border-color);
  border-radius: 50%;
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-normal);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.theme-toggle:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  fill: var(--text-primary);
  transition: fill var(--transition-normal);
}

/* Hero Section */
.hero {
  padding-top: clamp(3rem, 10vw, 5rem);
  display: flex;
  align-items: center;
  background: linear-gradient(135deg, var(--bg-light) 0%, var(--bg-white) 100%);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grid" width="10" height="10" patternUnits="userSpaceOnUse"><path d="M 10 0 L 0 0 0 10" fill="none" stroke="%23e2e8f0" stroke-width="0.5"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
  opacity: 0.3;
  z-index: 0;
  animation: float 20s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(1deg); }
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero h1 {
  margin-bottom: 1.5rem;
  animation: fadeInUp 1s ease-out;
}

.hero .lead {
  margin-bottom: 2rem;
  animation: fadeInUp 1s ease-out 0.2s both;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  justify-content: center;
  animation: fadeInUp 1s ease-out 0.4s both;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.btn {
  padding: 0.75rem 2rem;
  border-radius: 0.5rem;
  font-weight: 500;
  text-decoration: none;
  transition: all var(--transition-normal);
  border: none;
  cursor: pointer;
  display: inline-block;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left var(--transition-slow);
}

.btn:hover::before {
  left: 100%;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color), #1d4ed8);
  color: white;
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(37, 99, 235, 0.4);
}

.btn-outline {
  background: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn-outline:hover {
  background: var(--primary-color);
  color: white;
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(37, 99, 235, 0.3);
}

/* Projects Section */
.projects {
  background: var(--bg-light);
}

.project-item {
  background: var(--bg-white);
  border-radius: 1rem;
  padding: clamp(1.5rem, 4vw, 2.5rem);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
  border: 1px solid var(--border-color);
  margin-bottom: 2rem;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.project-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
  transform: scaleX(0);
  transition: transform var(--transition-normal);
}

.project-item:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.project-item:hover::before {
  transform: scaleX(1);
}

.project-header {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.project-header .project-emoji {
  font-size: clamp(2rem, 4vw, 2.5rem);
  line-height: 1;
  animation: float-emoji 3s ease-in-out infinite;
}

@keyframes float-emoji {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}

.project-header .project-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  margin: 0;
}

.project-tagline {
  font-size: clamp(1.1rem, 2vw, 1.2rem);
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 2rem;
}

.project-details h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-top: 1.5rem;
  margin-bottom: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--secondary-color);
}

.project-details p,
.project-details ul {
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.project-details ul {
  list-style: none;
  padding-left: 0;
}

.project-details ul li {
  position: relative;
  padding-left: 1.5rem;
  margin-bottom: 0.5rem;
}

.project-details ul li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--success-color);
  font-weight: bold;
}

.project-link {
  display: inline-block;
  margin-top: 1.5rem;
  color: var(--primary-color);
  text-decoration: none;
  font-weight: 500;
}

.project-link:hover {
  text-decoration: underline;
}

/* About Section */
.about {
  background: var(--bg-white);
}

.about-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.values-list {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.value-item {
  background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
  color: white;
  padding: 0.75rem 1.5rem;
  border-radius: 2rem;
  font-weight: 500;
  position: relative;
  transition: all var(--transition-normal);
  cursor: default;
}

.value-item:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(37, 99, 235, 0.3);
}

.value-item::before {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  right: -2px;
  bottom: -2px;
  background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
  border-radius: 2rem;
  z-index: -1;
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.value-item:hover::before {
  opacity: 1;
}

.value-item:first-child::before {
  display: none;
}

/* Testimonials Section */
.testimonials {
  background: var(--bg-white);
}

.testimonial-item {
  background: var(--bg-light);
  border-radius: 1rem;
  padding: 2rem;
  margin-bottom: 2rem;
  border: 1px solid var(--border-color);
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.testimonial-item::before {
  content: '"';
  position: absolute;
  top: -10px;
  left: 20px;
  font-size: 4rem;
  color: var(--primary-color);
  opacity: 0.1;
  font-family: serif;
}

.testimonial-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
}

.testimonial-content {
  margin-bottom: 1.5rem;
}

.testimonial-content p {
  font-style: italic;
  color: var(--text-secondary);
  line-height: 1.6;
  margin: 0;
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.author-info h4 {
  margin: 0;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.author-info span {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* Contact Section */
.contact {
  background: var(--bg-light);
}

.contact-form {
  max-width: 600px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-control {
  width: 100%;
  padding: 1rem;
  border: 2px solid var(--border-color);
  border-radius: 0.5rem;
  font-size: 1rem;
  transition: all var(--transition-normal);
  background: var(--bg-white);
  color: var(--text-primary);
}

.form-control:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
  transform: translateY(-2px);
}

textarea.form-control {
  min-height: 120px;
  resize: vertical;
}

/* Loading States */
.loading {
  position: relative;
  pointer-events: none;
}

.loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 20px;
  height: 20px;
  margin: -10px 0 0 -10px;
  border: 2px solid var(--border-color);
  border-top: 2px solid var(--primary-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* Success/Error States */
.form-control.success {
  border-color: var(--success-color);
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.1);
}

.form-control.error {
  border-color: var(--danger-color);
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.error-message {
  color: var(--danger-color);
  font-size: 0.875rem;
  margin-top: 0.5rem;
  display: none;
}

.error-message.show {
  display: block;
  animation: shake 0.5s ease-in-out;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-5px); }
  75% { transform: translateX(5px); }
}

.social-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-top: 2rem;
}

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  background: var(--bg-white);
  border: 2px solid var(--border-color);
  border-radius: 50%;
  color: var(--text-primary);
  text-decoration: none;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.social-link::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.social-link:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
  border-color: var(--primary-color);
}

.social-link:hover::before {
  opacity: 1;
}

.social-link svg {
  position: relative;
  z-index: 1;
  transition: fill var(--transition-normal);
}

.social-link:hover svg {
  fill: white;
}

/* Footer */
.footer {
  background: var(--bg-white);
  border-top: 1px solid var(--border-color);
  padding: 2rem 0;
  text-align: center;
  color: var(--text-secondary);
}

/* Scroll Progress Bar */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
  z-index: 1001;
  transition: width 0.1s ease;
}

/* Back to Top Button */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  background: var(--primary-color);
  color: white;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(37, 99, 235, 0.3);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}

/* Enhanced Mobile Responsiveness */
@media (max-width: 768px) {
  .hero h1 {
    font-size: clamp(2rem, 8vw, 3rem);
  }
  
  .hero .lead {
    font-size: clamp(1rem, 4vw, 1.25rem);
  }
  
  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }
  
  .btn {
    width: 100%;
    max-width: 300px;
    text-align: center;
  }
  
  .section-title {
    font-size: clamp(1.75rem, 6vw, 2.25rem);
  }
  
  .values-list {
    flex-direction: column;
    align-items: center;
    gap: 1rem;
  }
  
  .value-item::before {
    display: none;
  }
  
  .theme-toggle {
    top: 15px;
    right: 15px;
    width: 45px;
    height: 45px;
  }
  
  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 45px;
    height: 45px;
  }
  
  .testimonial-item {
    padding: 1.5rem;
  }
  
  .testimonial-author {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }
}

@media (max-width: 576px) {
  section {
    padding: clamp(2rem, 6vw, 3rem) 0;
  }
  
  .project-item {
    padding: 1.5rem;
    margin-bottom: 1.5rem;
  }
  
  .project-header {
    flex-direction: column;
    text-align: center;
    gap: 1rem;
  }
  
  .contact-form {
    padding: 0 1rem;
  }
  
  .social-links {
    gap: 1rem;
  }
  
  .social-link {
    width: 45px;
    height: 45px;
  }
  
  .testimonial-item {
    padding: 1rem;
  }
  
  .testimonial-item::before {
    font-size: 3rem;
    top: -5px;
    left: 15px;
  }
}

/* Print Styles */
@media print {
  .theme-toggle,
  .back-to-top,
  .scroll-progress {
    display: none !important;
  }
  
  .hero::before {
    display: none;
  }
  
  .project-item:hover {
    transform: none;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
  }
  
  .btn:hover {
    transform: none;
    box-shadow: none;
  }
  
  .testimonial-item:hover {
    transform: none;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
  }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  .hero::before {
    animation: none;
  }
  
  .project-header .project-emoji {
    animation: none;
  }
  
  .btn::before {
    transition: none;
  }
  
  .social-link::before {
    transition: none;
  }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
  :root {
    --primary-color: #0000ff;
    --text-primary: #000000;
    --text-secondary: #333333;
    --border-color: #000000;
  }
  
  .btn {
    border: 2px solid currentColor;
  }
  
  .project-item {
    border: 2px solid var(--border-color);
  }
  
  .testimonial-item {
    border: 2px solid var(--border-color);
  }
}

/* Focus Styles for Accessibility */
.btn:focus,
.social-link:focus,
.theme-toggle:focus,
.back-to-top:focus,
.form-control:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Skip Link for Accessibility */
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--primary-color);
  color: white;
  padding: 8px;
  text-decoration: none;
  border-radius: 4px;
  z-index: 10000;
}

.skip-link:focus {
  top: 6px;
}

/* Loading Skeleton */
.skeleton {
  background: linear-gradient(90deg, var(--border-color) 25%, var(--bg-light) 50%, var(--border-color) 75%);
  background-size: 200% 100%;
  animation: loading 1.5s infinite;
}

@keyframes loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}