/* ===================================
   AI Academy Website Styles
   Modern, Interactive, Dynamic Design
   =================================== */

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

:root {
  /* Color Palette - Modern AI Theme */
  --primary: #2563eb;
  --primary-dark: #1e40af;
  --primary-light: #3b82f6;
  --secondary: #8b5cf6;
  --accent: #06b6d4;
  --dark: #0f172a;
  --dark-light: #1e293b;
  --gray: #64748b;
  --gray-light: #cbd5e1;
  --gray-lighter: #f1f5f9;
  --white: #ffffff;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #2563eb 0%, #8b5cf6 100%);
  --gradient-hero: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(139, 92, 246, 0.1) 100%);

  /* Spacing */
  --container-width: 1200px;
  --section-padding: 100px 0;

  /* Typography */
  --font-primary: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans KR", sans-serif;

  /* Transitions */
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);

  /* 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);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  color: var(--dark);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ===================================
   Navigation
   =================================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  transition: var(--transition);
  padding: 20px 0;
}

.nav.scrolled {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-md);
  padding: 15px 0;
}

.nav-container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 24px;
  font-weight: 700;
  color: var(--dark);
  text-decoration: none;
}

.nav-logo img {
  width: 40px;
  height: 40px;
  border-radius: 8px;
}

.nav-menu {
  display: flex;
  gap: 40px;
  align-items: center;
}

.nav-link {
  color: var(--dark);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
  position: relative;
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: var(--transition);
}

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

.nav-link:hover::after {
  width: 100%;
}

.nav-cta {
  background: var(--gradient-primary);
  color: var(--white);
  border: none;
  padding: 12px 24px;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow-md);
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 5px;
}

.nav-toggle span {
  width: 25px;
  height: 3px;
  background: var(--dark);
  border-radius: 2px;
  transition: var(--transition);
}

/* ===================================
   Hero Section
   =================================== */
.hero {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  padding: 120px 20px 80px;
  overflow: hidden;
  max-width: var(--container-width);
  margin: 0 auto;
}

.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: -1;
}

.hero-grid {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: linear-gradient(rgba(37, 99, 235, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.03) 1px, transparent 1px);
  background-size: 50px 50px;
  animation: gridMove 20s linear infinite;
}

@keyframes gridMove {
  0% {
    transform: translate(0, 0);
  }
  100% {
    transform: translate(50px, 50px);
  }
}

.hero-gradient {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gradient-hero);
}

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

.hero-badge {
  display: inline-block;
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 24px;
  animation: fadeInUp 0.6s ease-out;
}

.hero-title {
  font-size: 64px;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 24px;
  animation: fadeInUp 0.6s ease-out 0.2s backwards;
}

.hero-title-line {
  display: block;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-description {
  font-size: 20px;
  color: var(--gray);
  margin-bottom: 40px;
  line-height: 1.8;
  animation: fadeInUp 0.6s ease-out 0.4s backwards;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  margin-bottom: 60px;
  animation: fadeInUp 0.6s ease-out 0.6s backwards;
}

.btn {
  padding: 16px 32px;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn-primary {
  background: var(--gradient-primary);
  color: var(--white);
  box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-xl);
}

.btn-secondary {
  background: var(--white);
  color: var(--dark);
  border: 2px solid var(--gray-light);
}

.btn-secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
  transform: translateY(-3px);
}

.hero-stats {
  display: flex;
  gap: 60px;
  animation: fadeInUp 0.6s ease-out 0.8s backwards;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-size: 48px;
  font-weight: 800;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 8px;
}

.stat-label {
  color: var(--gray);
  font-size: 14px;
}

.hero-visual {
  position: relative;
  width: 100%;
  height: 600px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-card {
  position: absolute;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-2xl);
  transition: var(--transition-slow);
  background: var(--white);
}

.hero-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-card-1 {
  width: 280px;
  height: 380px;
  top: 0;
  right: 100px;
  animation: float 6s ease-in-out infinite;
  z-index: 3;
}

.hero-card-2 {
  width: 320px;
  height: 280px;
  top: 50%;
  right: -20px;
  transform: translateY(-50%);
  animation: float 6s ease-in-out infinite 2s;
  z-index: 2;
}

.hero-card-3 {
  width: 260px;
  height: 320px;
  bottom: 20px;
  right: 120px;
  animation: float 6s ease-in-out infinite 4s;
  z-index: 1;
}

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

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

/* ===================================
   Section Styles
   =================================== */
section {
  padding: var(--section-padding);
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-badge {
  display: inline-block;
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.section-title {
  font-size: 48px;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--dark);
}

.section-description {
  font-size: 18px;
  color: var(--gray);
  line-height: 1.8;
}

/* ===================================
   About Section
   =================================== */
.about {
  background: var(--gray-lighter);
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
  margin-bottom: 60px;
}

.about-card {
  background: var(--white);
  padding: 40px;
  border-radius: 16px;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
}

.about-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.about-icon {
  width: 64px;
  height: 64px;
  background: var(--gradient-hero);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  color: var(--primary);
}

.about-card h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--dark);
}

.about-card p {
  color: var(--gray);
  line-height: 1.8;
}

.about-video {
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}

.video-placeholder {
  position: relative;
  cursor: pointer;
  overflow: hidden;
}

.video-placeholder img {
  width: 100%;
  height: auto;
  display: block;
  transition: var(--transition);
}

.video-placeholder:hover img {
  transform: scale(1.05);
}

.video-play-btn {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: none;
  border: none;
  cursor: pointer;
  transition: var(--transition);
}

.video-play-btn:hover {
  transform: translate(-50%, -50%) scale(1.1);
}

/* ===================================
   Programs Section
   =================================== */
.programs {
  background: var(--white);
}

.programs-tabs {
  display: flex;
  justify-content: center;
  gap: 16px;
  margin-bottom: 60px;
}

.tab-btn {
  padding: 12px 32px;
  border: 2px solid var(--gray-light);
  background: var(--white);
  color: var(--gray);
  border-radius: 12px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.tab-btn.active {
  background: var(--gradient-primary);
  color: var(--white);
  border-color: transparent;
}

.tab-btn:hover:not(.active) {
  border-color: var(--primary);
  color: var(--primary);
}

.tab-content {
  display: none;
  animation: fadeIn 0.5s ease-out;
}

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

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

.program-hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-bottom: 80px;
  padding: 60px;
  background: var(--gradient-hero);
  border-radius: 24px;
}

.program-hero-content h3 {
  font-size: 36px;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--dark);
}

.program-hero-content > p {
  font-size: 18px;
  color: var(--gray);
  margin-bottom: 32px;
  line-height: 1.8;
}

.program-features {
  list-style: none;
  margin-bottom: 32px;
}

.program-features li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 16px;
  font-size: 16px;
  color: var(--dark);
}

.program-features svg {
  flex-shrink: 0;
  margin-top: 2px;
  color: var(--primary);
}

.program-info {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 24px;
  background: var(--white);
  border-radius: 12px;
  box-shadow: var(--shadow-md);
}

.info-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--gray-light);
}

.info-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.info-item strong {
  color: var(--dark);
  font-weight: 700;
}

.info-item span {
  color: var(--gray);
}

.program-hero-image {
  border-radius: 16px;
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}

.program-hero-image img {
  width: 100%;
  height: auto;
  display: block;
}

.curriculum h4 {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 40px;
  color: var(--dark);
}

.curriculum-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.curriculum-card {
  background: var(--white);
  padding: 32px;
  border-radius: 16px;
  border: 2px solid var(--gray-light);
  transition: var(--transition);
}

.curriculum-card:hover {
  border-color: var(--primary);
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.curriculum-number {
  display: inline-block;
  width: 48px;
  height: 48px;
  background: var(--gradient-primary);
  color: var(--white);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 16px;
}

.curriculum-card h5 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--dark);
}

.curriculum-card p {
  color: var(--gray);
  line-height: 1.6;
}

/* ===================================
   Works Gallery
   =================================== */
.works {
  background: var(--gray-lighter);
}

.works-filter {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 60px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 10px 24px;
  border: 2px solid var(--gray-light);
  background: var(--white);
  color: var(--gray);
  border-radius: 24px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

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

.filter-btn:hover:not(.active) {
  border-color: var(--primary);
  color: var(--primary);
}

.works-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 30px;
  margin-bottom: 60px;
}

.work-card {
  background: var(--white);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  cursor: pointer;
}

.work-card.hidden {
  display: none;
}

.work-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.work-image {
  width: 100%;
  height: 400px;
  overflow: hidden;
}

.work-image img,
.work-image video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition);
}

.work-card:hover .work-image img {
  transform: scale(1.1);
}

.work-info {
  padding: 24px;
}

.work-info h4 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--dark);
}

.work-info p {
  color: var(--gray);
  margin-bottom: 12px;
}

.work-tag {
  display: inline-block;
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary);
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 600;
}

.works-cta {
  text-align: center;
  padding: 60px;
  background: var(--white);
  border-radius: 24px;
  box-shadow: var(--shadow-lg);
}

.works-cta p {
  font-size: 20px;
  color: var(--dark);
  margin-bottom: 24px;
  font-weight: 600;
}

.store-links {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.store-link {
  padding: 12px 32px;
  background: var(--gradient-primary);
  color: var(--white);
  text-decoration: none;
  border-radius: 12px;
  font-weight: 600;
  transition: var(--transition);
  box-shadow: var(--shadow-md);
}

.store-link:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

/* ===================================
   Testimonials
   =================================== */
.testimonials {
  background: var(--white);
  position: relative;
}

.testimonials-slider {
  display: flex;
  gap: 30px;
  overflow: hidden;
  margin-bottom: 40px;
}

.testimonial-card {
  min-width: calc(50% - 15px);
  background: var(--gradient-hero);
  padding: 40px;
  border-radius: 20px;
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
}

.testimonial-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

.testimonial-content {
  margin-bottom: 32px;
  position: relative;
}

.testimonial-quote {
  font-size: 80px;
  font-weight: 700;
  color: var(--primary);
  opacity: 0.2;
  line-height: 1;
  margin-bottom: -20px;
}

.testimonial-content p {
  font-size: 18px;
  line-height: 1.8;
  color: var(--dark);
}

.testimonial-author {
  display: flex;
  align-items: center;
  gap: 16px;
}

.author-avatar {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  overflow: hidden;
  border: 3px solid var(--white);
}

.author-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.author-info h5 {
  font-size: 18px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 4px;
}

.author-info span {
  font-size: 14px;
  color: var(--gray);
}

.slider-controls {
  display: flex;
  justify-content: center;
  gap: 16px;
}

.slider-btn {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 2px solid var(--gray-light);
  background: var(--white);
  color: var(--gray);
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}

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

/* ===================================
   Instructors Section
   =================================== */
.instructors {
  background: var(--white);
  padding: var(--section-padding);
}

.instructors-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  margin-top: 40px;
}

.instructor-card {
  background: var(--gradient-hero);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
  text-align: center;
  padding: 30px;
}

.instructor-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.instructor-image {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  overflow: hidden;
  margin: 0 auto 20px;
  border: 4px solid var(--white);
  box-shadow: var(--shadow-md);
}

.instructor-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.instructor-info h4 {
  font-size: 20px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 8px;
}

.instructor-info p {
  color: var(--gray);
  font-size: 14px;
}

@media (max-width: 1024px) {
  .instructors-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .instructors-grid {
    grid-template-columns: 1fr;
  }
}

/* ===================================
   Events Section
   =================================== */
.events {
  background: var(--gray-lighter);
}

.events-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px;
}

.event-card {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  transition: var(--transition);
}

.event-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-2xl);
}

.event-image {
  width: 100%;
  height: 400px;
  overflow: hidden;
}

.event-image img,
.event-image video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.event-content {
  padding: 32px;
}

.event-content h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--dark);
}

.event-content p {
  color: var(--gray);
  line-height: 1.8;
  margin-bottom: 24px;
}

.event-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
}

.event-link:hover {
  gap: 12px;
}

/* ===================================
   Contact Section
   =================================== */
.contact {
  background: var(--white);
}

.contact-wrapper {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: start;
}

.contact-info h2 {
  font-size: 42px;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--dark);
}

.contact-info > p {
  font-size: 18px;
  color: var(--gray);
  line-height: 1.8;
  margin-bottom: 40px;
}

.contact-details {
  margin-bottom: 40px;
}

.contact-item {
  display: flex;
  gap: 20px;
  margin-bottom: 32px;
}

.contact-icon {
  width: 48px;
  height: 48px;
  background: var(--gradient-hero);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  flex-shrink: 0;
}

.contact-item h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 8px;
}

.contact-item a {
  color: var(--primary);
  text-decoration: none;
  transition: var(--transition);
}

.contact-item a:hover {
  text-decoration: underline;
}

.contact-item p {
  color: var(--gray);
  line-height: 1.6;
}

.contact-benefits {
  padding: 24px;
  background: var(--gradient-hero);
  border-radius: 16px;
  border-left: 4px solid var(--primary);
}

.contact-benefits h4 {
  font-size: 18px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 16px;
}

.contact-benefits ul {
  list-style: none;
}

.contact-benefits li {
  color: var(--gray);
  margin-bottom: 8px;
  padding-left: 24px;
  position: relative;
}

.contact-benefits li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

.contact-form {
  background: var(--gradient-hero);
  padding: 40px;
  border-radius: 20px;
  box-shadow: var(--shadow-lg);
}

.form-group {
  margin-bottom: 24px;
}

/* Fixed backslash error and completed form styles */
.form-group label {
  display: block;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 8px;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 14px 16px;
  border: 2px solid var(--gray-light);
  border-radius: 8px;
  font-size: 16px;
  font-family: var(--font-primary);
  transition: var(--transition);
  background: var(--white);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

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

.form-submit {
  width: 100%;
  padding: 16px;
  background: var(--gradient-primary);
  color: var(--white);
  border: none;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

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

/* ===================================
   Footer
   =================================== */
.footer {
  background: var(--dark);
  color: var(--white);
  padding: 60px 0 30px;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 60px;
  margin-bottom: 40px;
}

.footer-brand h3 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 16px;
}

.footer-brand p {
  color: var(--gray-light);
  line-height: 1.8;
  margin-bottom: 24px;
}

.footer-social {
  display: flex;
  gap: 12px;
}

.social-link {
  width: 40px;
  height: 40px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  text-decoration: none;
  transition: var(--transition);
}

.social-link:hover {
  background: var(--primary);
  transform: translateY(-3px);
}

.footer-links h4 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 20px;
}

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

.footer-links li {
  margin-bottom: 12px;
}

.footer-links a {
  color: var(--gray-light);
  text-decoration: none;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--primary);
}

.footer-bottom {
  padding-top: 30px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
  color: var(--gray-light);
}

/* ===================================
   Video Modal
   =================================== */
.video-modal {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.9);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}

.video-modal.active {
  opacity: 1;
  visibility: visible;
}

.video-modal-content {
  position: relative;
  width: 90%;
  max-width: 1200px;
  aspect-ratio: 16 / 9;
}

.video-modal iframe {
  width: 100%;
  height: 100%;
  border: none;
  border-radius: 12px;
}

.video-modal-close {
  position: absolute;
  top: -50px;
  right: 0;
  background: none;
  border: none;
  color: var(--white);
  font-size: 36px;
  cursor: pointer;
  transition: var(--transition);
}

.video-modal-close:hover {
  color: var(--primary);
}

/* ===================================
   Animations
   =================================== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 1024px) {
  .hero {
    grid-template-columns: 1fr;
    padding: 100px 20px 60px;
  }

  .hero-visual {
    height: 400px;
  }

  .hero-title {
    font-size: 48px;
  }

  .program-hero {
    grid-template-columns: 1fr;
  }

  .curriculum-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .works-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .contact-wrapper {
    grid-template-columns: 1fr;
    gap: 60px;
  }

  .footer-content {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-menu {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background: var(--white);
    flex-direction: column;
    padding: 40px;
    transition: var(--transition);
    box-shadow: var(--shadow-xl);
  }

  .nav-menu.active {
    left: 0;
  }

  .nav-toggle {
    display: flex;
  }

  .hero-title {
    font-size: 36px;
  }

  .hero-description {
    font-size: 18px;
  }

  .hero-buttons {
    flex-direction: column;
  }

  .hero-stats {
    gap: 30px;
  }

  .section-title {
    font-size: 36px;
  }

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

  .programs-tabs {
    flex-wrap: wrap;
  }

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

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

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

  .testimonial-card {
    min-width: 100%;
  }

  .footer-content {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 28px;
  }

  .section-title {
    font-size: 28px;
  }

  .stat-number {
    font-size: 36px;
  }

  .btn {
    padding: 12px 24px;
    font-size: 14px;
  }
}

/* ===================================
   AI Tools Section
   =================================== */
.ai-tools {
  padding: var(--section-padding);
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  position: relative;
  overflow: hidden;
}

.ai-tools::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.3;
}

.ai-tools .section-header .section-badge {
  background: rgba(255, 255, 255, 0.2);
  color: white;
}

.ai-tools .section-title {
  color: white;
}

.ai-tools .section-description {
  color: rgba(255, 255, 255, 0.9);
}

.ai-category-section {
  margin-bottom: 60px;
  position: relative;
  z-index: 1;
}

.ai-category-title {
  font-size: 24px;
  font-weight: 700;
  color: white;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.ai-category-title::before {
  content: '#';
  color: rgba(255, 255, 255, 0.6);
}

.ai-tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 16px;
}

.ai-tool-card {
  background: rgba(255, 255, 255, 0.95);
  border-radius: 12px;
  padding: 20px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
  position: relative;
  text-decoration: none;
  color: inherit;
  display: block;
}

.ai-tool-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.2);
}

.ai-tool-card.locked {
  opacity: 0.5;
  cursor: not-allowed;
}

.ai-tool-card.locked:hover {
  transform: none;
}

.ai-tool-icon {
  font-size: 48px;
  margin-bottom: 12px;
}

.ai-tool-name {
  font-size: 14px;
  font-weight: 600;
  color: #333;
  word-break: break-word;
}

.lock-icon {
  position: absolute;
  top: 8px;
  right: 8px;
  font-size: 16px;
}

@media (max-width: 768px) {
  .ai-tools-grid {
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
    gap: 12px;
  }

  .ai-tool-card {
    padding: 16px;
  }

  .ai-tool-icon {
    font-size: 36px;
  }

  .ai-category-title {
    font-size: 20px;
  }
}