/* Colors */
:root {
  --primary: #1768c4;
  --primary-dark: #0d477f;
  --primary-light: #eef6ff;
  --accent: #f7c400;
  --dark: #122033;
  --text: #4b5563;
  --light: #f7f9fc;
  --white: #ffffff;
  --border: #e5e9ef;
  --shadow-sm: 0 3px 12px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 12px 30px rgba(15, 45, 80, 0.09);
  --transition: all 0.3s ease;
}

/* General */
html {
  scroll-behavior: smooth;
}

body {
  font-family: sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.6;
}

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

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

.container {
  width: min(1200px, 90%);
  margin: 0 auto;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 12px 20px;
  border: none;
  border-radius: 2px;
  font-size: 12px;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
}

.btn-yellow {
  background: var(--accent);
  color: #111;
}

.btn-yellow:hover {
  background: var(--white);
  transform: translateY(-2px);
}

.btn-blue {
  background: var(--primary);
  color: var(--white);
  box-shadow: 0 5px 15px rgba(23, 104, 196, 0.18);
}

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

/* Navbar */
.navbar {
  height: 68px;
  background: var(--white);
  border-bottom: 1px solid #edf0f4;
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.05);
  position: relative;
  z-index: 1000;
}

.navbar-flex {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 25px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--dark);
  font-size: 18px;
  font-weight: 800;
  white-space: nowrap;
}

.logo-accent {
  color: var(--primary);
}

.logo-mark {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--dark);
  color: var(--accent);
  font-size: 15px;
  font-weight: 800;
}

nav {
  margin-left: auto;
}

.nav-links {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-links a {
  position: relative;
  display: block;
  padding: 24px 0;
  color: #26384b;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1px;
  transition: var(--transition);
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 17px;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  transform: scaleX(1);
}

/* Hero */
.hero {
  position: relative;
  min-height: 620px;
  overflow: hidden;
  display: flex;
  align-items: stretch;
  background: #0d477f;
}
.hero::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  background:
    linear-gradient(to right, #0d477f 0%, rgba(13, 71, 127, 0.35) 35%, rgba(13, 71, 127, 0) 100%),
    url("student.jpg") left/cover no-repeat;
  z-index: 1;
}

.hero-content {
  width: 100%;
  display: flex;
  align-items: center;
  position: relative;
  z-index: 3;
  padding: 40px 20px 180px;
}

.hero-text {
  max-width: 760px;
  margin: 0 auto;
  color: var(--white);
  text-align: left;
}

.hero-text h1 {
  margin-bottom: 15px;
  color: var(--white);
  font-size: 60px;
  line-height: 1.08;
  font-weight: 800;
  letter-spacing: -1.4px;
}

.hero-text p {
  max-width: 650px;
  margin: 0 auto 22px;
  color: rgba(255, 255, 255, 0.92);
  font-size: 16px;
  line-height: 1.75;
}

.hero-buttons {
  display: flex;
  justify-content: flex-start;
  gap: 15px;
  margin-top: 25px;
}

.hero-features {
  position: absolute;
  left: 50%;
  bottom: 0;
  z-index: 3;
  width: min(900px, 90%);
  transform: translateX(-50%);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  background: rgba(7, 46, 86, 0.92);
}

.feature-box {
  min-height: 80px;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 13px;
  padding: 15px 20px;
  text-align: center;
  color: var(--white);
  border-right: 1px solid rgba(255, 255, 255, 0.2);
}

.feature-box:last-child {
  border-right: none;
}

.feature-icon {
  flex: 0 0 28px;
  color: var(--accent);
  text-align: center;
  font-size: 23px;
  line-height: 1;
}

.feature-box h2 {
  margin-bottom: 4px;
  color: var(--white);
  font-size: 18px;
  font-weight: 700;
}

.feature-box p {
  color: rgba(255, 255, 255, 0.82);
  font-size: 18px;
  line-height: 1.5;
}

/* Section headers */
.section-header {
  max-width: 700px;
  margin: 0 auto 45px;
  text-align: center;
}

.section-tagline {
  margin-bottom: 8px;
  color: var(--primary);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
}

.section-title {
  color: var(--dark);
  font-size: clamp(28px, 4vw, 36px);
  line-height: 1.2;
  font-weight: 800;
}

/* Lesson content */
.services {
  padding: 85px 0;
  background: var(--light);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.services-grid,
.why-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 25px;
}

.service-card {
  padding: 32px 28px;
  background: var(--white);
  text-align: center;
  border: 1px solid var(--border);
  border-radius: 10px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.service-card:hover {
  transform: translateY(-7px);
  border-color: rgba(23, 104, 196, 0.25);
  box-shadow: var(--shadow-md);
}

.service-icon {
  width: 55px;
  height: 55px;
  margin: 0 auto 20px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background: var(--primary-light);
  color: var(--primary);
}

.service-icon .material-symbols-outlined {
  font-size: 28px;
}

.service-card h3 {
  margin-bottom: 10px;
  color: var(--dark);
  font-size: 19px;
  line-height: 1.3;
}

.service-card p,
.why-text {
  color: var(--text);
  font-size: 14px;
  line-height: 1.7;
}

.center-btn {
  margin-top: 35px;
  text-align: center;
}

/* Why learn */
.why-choose {
  padding: 85px 0;
  background: var(--white);
}

.why-item {
  padding: 30px;
  background: var(--white);
  text-align: center;
  border: 1px solid var(--border);
  border-radius: 10px;
  transition: var(--transition);
}

.why-item:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
  transform: translateY(-4px);
}

.why-item-heading {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  margin-bottom: 17px;
}

.why-num {
  color: var(--primary);
  font-size: 25px;
  font-weight: 800;
}

.why-divider {
  width: 2px;
  height: 25px;
  background: var(--border);
}

.why-title {
  color: var(--dark);
  font-size: 16px;
  line-height: 1.35;
}

/* Stats */
.stats {
  padding: 70px 0;
  background: var(--primary-light);
  border-top: 1px solid var(--border);
}

.stats-flex {
  display: flex;
  align-items: center;
  gap: 50px;
}

.experience-card {
  flex: 1;
  max-width: 390px;
  padding: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
}

.experience-number {
  flex: 0 0 auto;
  padding: 12px 16px;
  border-radius: 9px;
  background: var(--primary);
  color: var(--white);
  font-size: 25px;
  font-weight: 800;
}

.experience-label {
  color: var(--dark);
  font-size: 15px;
  font-weight: 700;
  line-height: 1.4;
}

.stats-list {
  flex: 2;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 25px;
}

.stat-box {
  padding: 10px;
  text-align: center;
}

.stat-value {
  display: block;
  margin-bottom: 5px;
  color: var(--primary);
  font-size: 38px;
  line-height: 1;
  font-weight: 800;
}

.stat-name {
  color: var(--text);
  font-size: 13px;
  font-weight: 600;
}

/* Footer */
.footer {
  padding: 65px 0 30px;
  background: var(--dark);
  text-align: center;
  color: #9ca3af;
}

.footer h3 {
  margin-bottom: 12px;
  color: var(--white);
  font-size: 21px;
}

.footer p {
  max-width: 650px;
  margin: 0 auto 25px;
  font-size: 13px;
  line-height: 1.8;
}

.footer hr {
  margin: 25px 0;
  border: none;
  border-top: 1px solid #263244;
}

.footer-info {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 15px;
  flex-wrap: wrap;
  font-size: 12px;
}

.footer-info strong {
  color: var(--white);
}

.footer-copy {
  color: #6b7280;
}

/* Tablet */
@media (max-width: 1000px) {
  .nav-links {
    gap: 15px;
  }

  .hero-features {
    width: 90%;
  }

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

/* Mobile */
@media (max-width: 800px) {
  .navbar {
    height: auto;
    min-height: 65px;
  }

  .navbar-flex {
    padding: 12px 0;
  }

  nav {
    display: none;
  }

  .hero {
    min-height: 650px;
  }

  .hero-content {
    padding: 30px 15px 220px;
  }

  .hero-text {
    max-width: 650px;
  }

  .hero-text h1 {
    font-size: 38px;
  }

  .hero-features {
    width: 90%;
    grid-template-columns: 1fr;
  }

  .feature-box {
    min-height: auto;
    border-right: none;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  }

  .feature-box:last-child {
    border-bottom: none;
  }

  .stats-flex {
    flex-direction: column;
    align-items: stretch;
  }

  .experience-card {
    max-width: none;
  }
}

/* Small mobile */
@media (max-width: 600px) {
  .container {
    width: 92%;
  }

  .logo {
    font-size: 15px;
  }

  .hero {
    min-height: 680px;
    background-position: 62% center;
  }

  .hero-content {
    padding: 30px 15px 240px;
  }

  .hero-text h1 {
    font-size: 32px;
  }

  .hero-text p {
    max-width: 100%;
    font-size: 11px;
  }

  .services,
  .why-choose {
    padding: 65px 0;
  }

  .services-grid,
  .why-grid,
  .stats-list {
    grid-template-columns: 1fr;
  }

  .stats-list {
    gap: 12px;
  }

  .stat-box {
    padding: 15px 0;
    border-bottom: 1px solid var(--border);
  }

  .stat-box:last-child {
    border-bottom: none;
  }
}