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

:root {
  --primary-blue: #0056b3;
  --light-blue: #e7f1ff;
  --dark-blue: #003d82;
  --white: #ffffff;
  --light-gray: #f8f9fa;
  --dark-gray: #333333;
  --border-gray: #dee2e6;
  --success-green: #28a745;
}

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--dark-gray);
  background-color: var(--white);
  line-height: 1.6;
}

header {
  background-color: var(--white);
  border-bottom: 2px solid var(--light-blue);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.navbar-brand {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--primary-blue);
  text-decoration: none;
}

.nav-link {
  color: var(--dark-gray) !important;
  font-weight: 500;
  transition: color 0.3s ease;
}

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

.nav-link.active {
  color: var(--primary-blue) !important;
  border-bottom: 3px solid var(--primary-blue);
}

.hero {
  background: linear-gradient(135deg, var(--light-blue) 0%, var(--white) 100%);
  padding: 4rem 0;
  text-align: center;
}

.hero h1 {
  font-size: 2.5rem;
  color: var(--dark-blue);
  margin-bottom: 1rem;
  font-weight: 700;
}

.hero p {
  font-size: 1.2rem;
  color: var(--dark-gray);
  margin-bottom: 2rem;
}

.btn-primary {
  background-color: var(--primary-blue);
  border-color: var(--primary-blue);
  color: var(--white);
  padding: 0.75rem 2rem;
  font-weight: 600;
  transition: all 0.3s ease;
}

.btn-primary:hover {
  background-color: var(--dark-blue);
  border-color: var(--dark-blue);
  color: var(--white);
}

.btn-secondary {
  background-color: transparent;
  border: 2px solid var(--primary-blue);
  color: var(--primary-blue);
  padding: 0.75rem 2rem;
  font-weight: 600;
  transition: all 0.3s ease;
}

.btn-secondary:hover {
  background-color: var(--primary-blue);
  color: var(--white);
}

.section {
  padding: 4rem 0;
}

.section-title {
  font-size: 2rem;
  color: var(--dark-blue);
  margin-bottom: 3rem;
  text-align: center;
  font-weight: 700;
}

.card {
  border: 1px solid var(--border-gray);
  border-radius: 8px;
  transition: all 0.3s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.card:hover {
  box-shadow: 0 8px 16px rgba(0, 86, 179, 0.15);
  transform: translateY(-4px);
}

.card-title {
  color: var(--primary-blue);
  font-weight: 700;
}

.service-icon {
  font-size: 3rem;
  color: var(--primary-blue);
  margin-bottom: 1rem;
}

.testimonial {
  background-color: var(--light-gray);
  padding: 2rem;
  border-radius: 8px;
  border-left: 4px solid var(--primary-blue);
}

.testimonial-author {
  font-weight: 700;
  color: var(--dark-blue);
  margin-top: 1rem;
}

.form-control {
  border: 1px solid var(--border-gray);
  border-radius: 4px;
  padding: 0.75rem;
  font-size: 1rem;
}

.form-control:focus {
  border-color: var(--primary-blue);
  box-shadow: 0 0 0 0.2rem rgba(0, 86, 179, 0.25);
}

.form-check-input:checked {
  background-color: var(--primary-blue);
  border-color: var(--primary-blue);
}

footer {
  background-color: var(--dark-gray);
  color: var(--white);
  padding: 3rem 0 1rem;
  margin-top: 4rem;
}

.footer-section h5 {
  color: var(--light-blue);
  font-weight: 700;
  margin-bottom: 1rem;
}

.footer-link {
  color: #cccccc;
  text-decoration: none;
  transition: color 0.3s ease;
  display: block;
  margin-bottom: 0.5rem;
}

.footer-link:hover {
  color: var(--light-blue);
}

.footer-bottom {
  border-top: 1px solid #555555;
  padding-top: 2rem;
  margin-top: 2rem;
  text-align: center;
  color: #999999;
}

.bmi-calculator {
  background-color: var(--light-blue);
  padding: 2rem;
  border-radius: 8px;
  margin: 2rem 0;
}

.bmi-result {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-blue);
  margin-top: 1rem;
}

.alert-info {
  background-color: var(--light-blue);
  border: 1px solid var(--primary-blue);
  color: var(--dark-blue);
  padding: 1rem;
  border-radius: 4px;
  margin-bottom: 1rem;
}

.img-fluid {
  max-width: 100%;
  height: auto;
}

@media (max-width: 768px) {
  .hero h1 {
    font-size: 1.8rem;
  }

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

  .section-title {
    font-size: 1.5rem;
  }

  .nav-link {
    padding: 0.5rem 0 !important;
  }

  footer {
    padding: 2rem 0 1rem;
  }
}

@media (max-width: 576px) {
  .hero {
    padding: 2rem 0;
  }

  .section {
    padding: 2rem 0;
  }

  .hero h1 {
    font-size: 1.5rem;
  }

  .btn-primary,
  .btn-secondary {
    padding: 0.6rem 1.5rem;
    font-size: 0.9rem;
  }
}