html {
  font-size: 14px;
}

@media (min-width: 768px) {
  html {
    font-size: 16px;
  }
}

.btn:focus, .btn:active:focus, .btn-link.nav-link:focus, .form-control:focus, .form-check-input:focus {
  box-shadow: 0 0 0 0.1rem white, 0 0 0 0.25rem #258cfb;
}

html {
  position: relative;
  min-height: 100%;
}

/* Background đẹp với overlay mờ */
body.custom-background {
    background: url('/images/background.jpg') no-repeat center center fixed;
    background-size: cover;
    min-height: 100vh;
    position: relative;
}

body::after {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5); /* Lớp phủ mờ */
    z-index: -1;
}

/* Navbar trong suốt */
.navbar {
    background-color: rgba(0, 0, 0, 0.7) !important;
    border-radius: 0 0 15px 15px;
}

    .navbar a {
        color: white !important;
        font-weight: bold;
    }

        .navbar a:hover {
            color: #ffd700 !important;
            text-decoration: underline;
        }

/* Hiệu ứng card gallery */
.card-gallery {
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: 15px;
    padding: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s, box-shadow 0.3s;
}

    .card-gallery:hover {
        transform: scale(1.05);
        box-shadow: 0 8px 16px rgba(0, 0, 0, 0.4);
    }

h1, h2, h3, p {
    color: white;
    text-shadow: 1px 1px 2px black;
}