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

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.6;
}

/* =========================
   HERO SECTION
   ========================= */
.hero-section {
  background: linear-gradient(135deg, #0b2d5c, #081f3a);
}

/* =========================
   GLOBAL IMAGE
   ========================= */
img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  border-radius: 12px;
}

/* =========================
   CARD
   ========================= */
.card {
  border-radius: 16px;
  overflow: hidden;
  transition: transform 0.3s ease;
}

.card:hover {
  transform: translateY(-4px);
}

/* =========================
   GRADIENT BORDER BANNER
   ========================= */
.banner-box {
  position: relative;
  width: 100%;
  max-width: 1100px;
  margin-inline: auto;
  padding: 4px; /* border thickness */
  border-radius: 20px;
  overflow: hidden;
}

/* Animated gradient border */
.banner-box::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(90deg, #6a11cb, #2575fc, #00c6ff, #6a11cb);
  background-size: 300% 300%;
  animation: snakeMove 4s linear infinite;
  z-index: 0;
}

/* Image inside banner */
.banner-box img {
  position: relative;
  z-index: 1;
  border-radius: 16px;
}

/* =========================
   ANIMATION
   ========================= */
@keyframes snakeMove {
  from {
    background-position: 0% 50%;
  }
  to {
    background-position: 300% 50%;
  }
}

/* Tablet & Mobile */
@media (max-width: 768px) {
  /* Space below CTA buttons */
  .hero-section .mt-4 {
    margin-bottom: 20px;
  }

  /* Space above banner image */
  .banner-box {
    margin-top: 20px;
  }
}

/* Mobile */
@media (max-width: 480px) {
  .banner-box {
    padding: 2px; /* FIXED: thin border */
    border-radius: 14px;
  }

  .banner-box img {
    border-radius: 12px;
  }

  body {
    font-size: 14px;
  }

  h1 {
    font-size: 22px;
  }

  h2 {
    font-size: 20px;
  }

  .btn {
    width: 100%;
    margin-bottom: 10px;
  }
}

/* =========================
   NAVBAR
   ========================= */
header {
  position: sticky;
  top: 0;
  z-index: 1020;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.navbar-nav {
  text-align: center;
}

.navbar-nav .nav-link {
  padding: 10px 0;
}

/* =========================
   FOOTER
   ========================= */
footer {
  padding: 1.2rem 0;
}