/* ===== RESET & BASE ===== */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: "Inter", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: #3a3a4a;
  background: #fff;
  padding-top: 68px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  display: block;
}

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
}

/* ===== UTILITIES ===== */
.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 72px 0;
}

.section-title {
  font-size: 1.75rem;
  font-weight: 700;
  color: #0f1b3d;
  margin-bottom: 40px;
  text-align: center;
  letter-spacing: -0.02em;
}

.section-subtitle {
  text-align: center;
  color: #666;
  font-size: 1.05rem;
  max-width: 540px;
  margin: -24px auto 40px;
  line-height: 1.6;
}

/* ===== FADE-IN ANIMATION ===== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition:
    opacity 0.6s ease,
    transform 0.6s ease;
}

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

/* ===== BUTTON ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition:
    background-color 0.25s ease,
    box-shadow 0.25s ease,
    transform 0.15s ease;
  line-height: 1.2;
}

.btn-primary {
  background: #1a56db;
  color: #fff;
  box-shadow: 0 2px 8px rgba(26, 86, 219, 0.25);
}

.btn-primary:hover {
  background: #1544b0;
  box-shadow: 0 4px 16px rgba(26, 86, 219, 0.35);
  transform: translateY(-1px);
}

.btn-primary:active {
  transform: translateY(0);
}

/* ===== HEADER (Glassmorphism Navbar) ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: rgba(255, 255, 255, 0.7);
  border-bottom: 1px solid rgba(255, 255, 255, 0.35);
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition:
    background 0.3s ease,
    box-shadow 0.3s ease,
    border-color 0.3s ease;
}

/* Scrolled state — applied via JS */
.header.scrolled {
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  border-bottom-color: rgba(234, 237, 243, 0.8);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.logo {
  font-size: 1.15rem;
  font-weight: 700;
  color: #1a56db;
  letter-spacing: -0.01em;
}

.nav {
  display: flex;
  gap: 32px;
}

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: #555;
  transition: color 0.2s ease;
  position: relative;
}

.nav-link:hover {
  color: #1a56db;
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: #1a56db;
  transition: width 0.25s ease;
}

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

/* Hamburger */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.menu-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: #333;
  border-radius: 2px;
  transition:
    transform 0.25s ease,
    opacity 0.25s ease;
}

.menu-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ===== HERO ===== */
.hero {
  background: url("../hero-bg.webp") center/cover no-repeat;
  position: relative;
  padding: 88px 0 96px;
  text-align: center;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(15, 27, 61, 0.72);
}

.hero-inner {
  max-width: 640px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

/* Hero glassmorphism card */
.hero-glass {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 16px;
  padding: 48px 40px;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
}

.hero-badge {
  display: inline-block;
  background: rgba(255, 255, 255, 0.18);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 6px 16px;
  border-radius: 20px;
  margin-bottom: 24px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  border: 1px solid rgba(255, 255, 255, 0.3);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}

.hero h1 {
  font-size: 2.5rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 16px;
  letter-spacing: -0.03em;
  line-height: 1.2;
}

.hero-sub {
  font-size: 1.1rem;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 32px;
  line-height: 1.6;
}

/* ===== COURSES ===== */
.courses {
  background: #fff;
}

.course-card {
  background: rgba(255, 255, 255, 0.65);
  border: 1px solid rgba(255, 255, 255, 0.6);
  border-radius: 12px;
  padding: 40px;
  max-width: 620px;
  margin: 0 auto;
  text-align: left;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.05);
  position: relative;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition:
    box-shadow 0.3s ease,
    transform 0.2s ease;
}

.course-card:hover {
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  transform: translateY(-3px);
}

.course-card-badge {
  display: inline-block;
  background: #e8f5e9;
  color: #2e7d32;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 4px;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.course-card h3 {
  font-size: 1.35rem;
  font-weight: 700;
  color: #0f1b3d;
  margin-bottom: 12px;
}

.course-card > p {
  color: #555;
  margin-bottom: 24px;
  line-height: 1.7;
}

.course-details {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 28px;
}

.course-detail-group h4 {
  font-size: 0.88rem;
  font-weight: 600;
  color: #0f1b3d;
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.course-highlights {
  margin-bottom: 0;
}

.course-highlights li {
  padding: 5px 0 5px 20px;
  position: relative;
  color: #444;
  font-size: 0.9rem;
  line-height: 1.5;
}

.course-highlights li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 7px;
  height: 7px;
  background: #1a56db;
  border-radius: 50%;
}

/* ===== WHY CHOOSE US ===== */
.why-us {
  background: #f8f9fc;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.feature-card {
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.5);
  border-radius: 10px;
  padding: 28px 20px;
  text-align: center;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.04);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition:
    box-shadow 0.3s ease,
    transform 0.2s ease;
}

.feature-card:hover {
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.08);
  transform: translateY(-3px);
}

.feature-icon {
  color: #1a56db;
  margin-bottom: 14px;
}

.feature-card h3 {
  font-size: 1rem;
  font-weight: 600;
  color: #0f1b3d;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 0.88rem;
  color: #666;
  line-height: 1.5;
}

/* ===== TEACHING METHOD ===== */
.teaching-method {
  background: #fff;
}

.method-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.method-card {
  background: #f8f9fc;
  border: 1px solid #eaedf3;
  border-radius: 10px;
  padding: 32px 28px;
  transition:
    box-shadow 0.3s ease,
    transform 0.2s ease;
}

.method-card:hover {
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.06);
  transform: translateY(-2px);
}

.method-icon {
  color: #1a56db;
  margin-bottom: 16px;
}

.method-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: #0f1b3d;
  margin-bottom: 8px;
}

.method-card p {
  font-size: 0.92rem;
  color: #555;
  line-height: 1.65;
}

/* ===== TEACHERS ===== */
.teachers {
  background: #f8f9fc;
}

.teachers-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
  max-width: 680px;
  margin: 0 auto;
}

.teacher-card {
  background: #fff;
  border: 1px solid #eaedf3;
  border-radius: 12px;
  padding: 36px 28px;
  text-align: center;
  box-shadow: 0 1px 6px rgba(0, 0, 0, 0.03);
  transition:
    box-shadow 0.3s ease,
    transform 0.2s ease;
}

.teacher-card:hover {
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.07);
  transform: translateY(-2px);
}

.teacher-photo-placeholder {
  width: 96px;
  height: 96px;
  border-radius: 50%;
  background: #eef2f9;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  color: #9aa8c7;
}

.teacher-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: #0f1b3d;
  margin-bottom: 8px;
}

.teacher-card p {
  font-size: 0.9rem;
  color: #666;
  line-height: 1.6;
}

/* ===== ABOUT ===== */
.about {
  background: #fff;
}

.about-content {
  max-width: 680px;
  margin: 0 auto;
  text-align: center;
}

.about-content p {
  color: #555;
  font-size: 1.05rem;
  line-height: 1.8;
  margin-bottom: 16px;
}

.about-content p:last-child {
  margin-bottom: 0;
}

/* ===== CONTACT ===== */
.contact {
  background: #f8f9fc;
}

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

.contact-item {
  background: #fff;
  border: 1px solid #eaedf3;
  border-radius: 10px;
  padding: 32px 24px;
  box-shadow: 0 1px 6px rgba(0, 0, 0, 0.03);
  transition:
    box-shadow 0.3s ease,
    transform 0.2s ease;
}

.contact-item:hover {
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.06);
  transform: translateY(-2px);
}

.contact-icon {
  color: #1a56db;
  margin-bottom: 14px;
}

.contact-item h3 {
  font-size: 1rem;
  font-weight: 600;
  color: #0f1b3d;
  margin-bottom: 10px;
}

.contact-item p {
  color: #555;
  font-size: 0.95rem;
  line-height: 1.6;
}

/* ===== FOOTER ===== */
.footer {
  background: #0f1b3d;
  color: #b0b8cc;
  padding: 36px 0;
  text-align: center;
}

.footer-inner p {
  margin-bottom: 6px;
  font-size: 0.88rem;
}

.footer-name {
  font-weight: 600;
  color: #fff;
  font-size: 1rem;
  margin-bottom: 8px;
}

/* ===== RESPONSIVE ===== */

/* Tablet */
@media (max-width: 768px) {
  .menu-toggle {
    display: flex;
  }

  .nav {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.85);
    border-bottom: 1px solid rgba(255, 255, 255, 0.4);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
    padding: 20px 24px;
    gap: 16px;
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
  }

  .nav.open {
    display: flex;
  }

  .hero {
    padding: 64px 0 72px;
  }

  .hero h1 {
    font-size: 2rem;
  }

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

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

  .course-details {
    grid-template-columns: 1fr;
    gap: 20px;
  }

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

  .contact-grid {
    grid-template-columns: 1fr;
    gap: 16px;
    max-width: 400px;
    margin: 0 auto;
  }
}

/* Mobile */
@media (max-width: 480px) {
  .section {
    padding: 56px 0;
  }

  .section-title {
    font-size: 1.5rem;
    margin-bottom: 32px;
  }

  .section-subtitle {
    font-size: 0.95rem;
    margin-top: -16px;
    margin-bottom: 32px;
  }

  .hero {
    padding: 52px 0 60px;
  }

  .hero-glass {
    padding: 32px 24px;
  }

  .hero h1 {
    font-size: 1.65rem;
  }

  .hero-sub {
    font-size: 1rem;
  }

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

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

  .teachers-grid {
    grid-template-columns: 1fr;
    max-width: 320px;
  }

  .course-card {
    padding: 28px 24px;
  }

  .btn {
    padding: 12px 24px;
    font-size: 0.9rem;
  }
}