:root {
    --primary-color: #0d47a1; /* Koyu Mavi */
    --secondary-color: #007bff; /* Standart Mavi */
    --accent-color: #17a2b8; /* Turkuaz */
    --light-bg: #f8f9fa;
    --primary-hover: #0b3a84;
}

/* Navbar */
#main-nav {
    background-color: var(--primary-color) !important;
}

#main-nav .navbar-brand {
    font-weight: bold;
}

#main-nav .nav-link {
    color: rgba(255,255,255,.85) !important;
}

#main-nav .nav-link:hover, #main-nav .nav-link.active {
    color: white !important;
}


/* Butonlar */
.btn-primary {
    background-color: var(--secondary-color);
    border-color: var(--secondary-color);
}
.btn-primary:hover {
    background-color: var(--primary-hover);
    border-color: var(--primary-hover);
}

.btn-secondary {
    background-color: var(--accent-color);
    border-color: var(--accent-color);
    color: white;
}
.btn-secondary:hover {
    background-color: #138496;
    border-color: #138496;
}

/* Card Başlıkları */
.card-header {
    background-color: var(--primary-color);
    color: white;
    font-weight: bold;
}

/* Jumbotron/Hero Alanı */
.hero-section {
    background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 4rem 2rem;
    border-radius: 0.5rem;
}

.hero-section .display-4 {
    font-weight: 300;
}