/* =============== GLOBAL RESET =============== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Poppins", sans-serif;
  background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
  color: #f4f4f4;
  line-height: 1.6;
  overflow-x: hidden;
}

/* =============== HEADERS / TYPOGRAPHY =============== */
h1, h2, h3, h4 {
  font-weight: 700;
  color: #fff;
}

p {
  color: #dcdcdc;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.3s ease;
}

a:hover {
  color: #00eaff;
}

/* =============== NAVBAR =============== */
.navbar {
  background: rgba(20, 20, 20, 0.7);
  backdrop-filter: blur(15px);
  box-shadow: 0 4px 30px rgba(0,0,0,0.4);
  padding: 1rem 2rem;
}

.navbar-brand {
  font-size: 1.6rem;
  font-weight: 800;
  background: linear-gradient(45deg, #00eaff, #ff00c8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-link {
  font-weight: 500;
  margin: 0 10px;
  color: #eee !important;
  transition: all 0.3s ease;
}

.nav-link:hover {
  color: #00eaff !important;
}

/* =============== HERO SECTION =============== */
.hero {
  min-height: 80vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  background: url('../img/hero-illustration.svg') no-repeat center/contain;
  padding: 2rem;
}

.hero h1 {
  font-size: 3rem;
  background: linear-gradient(90deg, #00eaff, #ff00c8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  margin: 1rem 0 2rem;
  font-size: 1.2rem;
}

.hero .btn {
  padding: 0.8rem 2rem;
  font-size: 1.1rem;
  border-radius: 50px;
  background: linear-gradient(45deg, #00eaff, #ff00c8);
  border: none;
  color: #fff;
  transition: transform 0.3s ease;
}

.hero .btn:hover {
  transform: translateY(-3px) scale(1.05);
}

/* =============== COURSE CATEGORIES GRID =============== */
.categories {
  padding: 4rem 2rem;
  text-align: center;
}

.categories h2 {
  margin-bottom: 2rem;
  font-size: 2.2rem;
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.category-card {
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(12px);
  border-radius: 16px;
  padding: 2rem 1.5rem;
  transition: all 0.4s ease;
  cursor: pointer;
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.category-card:hover {
  transform: translateY(-8px);
  background: linear-gradient(145deg, rgba(0,234,255,0.2), rgba(255,0,200,0.2));
  box-shadow: 0 8px 30px rgba(0,0,0,0.6);
}

.category-card i {
  font-size: 2rem;
  color: #00eaff;
  margin-bottom: 1rem;
}

.category-card h3 {
  margin-bottom: 0.5rem;
  font-size: 1.3rem;
}

/* =============== FEATURED COURSES SECTION =============== */
.featured {
  padding: 4rem 2rem;
}

.course-card {
  background: rgba(255,255,255,0.08);
  border-radius: 16px;
  overflow: hidden;
  transition: all 0.4s ease;
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.course-card img {
  width: 100%;
  height: 160px;
  object-fit: cover;
}

.course-card .card-body {
  padding: 1rem;
}

.course-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 8px 30px rgba(0,0,0,0.6);
}

/* =============== CTA SECTION =============== */
.cta {
  background: linear-gradient(135deg, #00eaff, #ff00c8);
  color: #fff;
  text-align: center;
  padding: 4rem 2rem;
  border-radius: 20px;
  margin: 3rem auto;
  max-width: 900px;
}

.cta h2 {
  margin-bottom: 1.5rem;
  font-size: 2.2rem;
}

.cta .btn {
  background: #fff;
  color: #111;
  border-radius: 50px;
  padding: 0.8rem 2rem;
  font-weight: 600;
  transition: all 0.3s ease;
}

.cta .btn:hover {
  background: #111;
  color: #fff;
}

/* =============== FOOTER =============== */
footer {
  background: rgba(10,10,10,0.9);
  padding: 2rem;
  text-align: center;
  font-size: 0.9rem;
  margin-top: 4rem;
}

footer a {
  margin: 0 10px;
  color: #00eaff;
}

/* =============== ANIMATIONS =============== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero, .categories, .featured, .cta {
  animation: fadeInUp 1.2s ease forwards;
}