/* General Reset & Typography */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    background-color: #f4f7f6;
    color: #333;
}

/* Header & Navigation */
.main-header {
    background-color: #00b0c7;
    padding: 1rem 5%;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
}

.nav-links {
    list-style: none;
    display: flex;
}

.nav-links li {
    margin-left: 20px;
}

.nav-links a {
    text-decoration: none;
    color: white;
    font-weight: 500;
    transition: opacity 0.3s;
}

.nav-links a:hover {
    opacity: 0.8;
}

/* Hero Section */
.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 40px 20px;
}

.hero-section {
    text-align: center;
    padding-bottom: 30px;
}

.hero-section h1 {
    color: #2c3e50;
    font-size: 2.2rem;
    margin-bottom: 10px;
}

.subtitle {
    color: #27ae60;
    font-weight: bold;
    font-size: 1.1rem;
}

.intro-text {
    background: white;
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 30px;
    border-left: 5px solid #00b0c7;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

/* Grid Layout for COC Tests */
.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.test-card {
    background: white;
    text-decoration: none;
    color: #333;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid #eee;
}

.test-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    border-color: #00b0c7;
}

.card-icon {
    font-size: 2.5rem;
    display: block;
    margin-bottom: 15px;
}

.test-card h3 {
    margin-bottom: 10px;
    color: #2980b9;
}

.test-card p {
    font-size: 0.9rem;
    color: #666;
}

/* Highlighting the Quiz Button */
.highlight {
    background: #e8f8f5;
    border: 2px solid #1abc9c;
}

/* Footer */
.main-footer {
    background: #2c3e50;
    color: white;
    padding: 40px 0;
    margin-top: 50px;
    text-align: center;
}

.footer-nav {
    margin-top: 15px;
}

.footer-nav a {
    color: #bdc3c7;
    text-decoration: none;
    margin: 0 10px;
    font-size: 0.9rem;
}

.footer-nav a:hover {
    color: white;
}

/* Mobile Responsive */
@media (max-width: 600px) {
    .navbar {
        flex-direction: column;
    }
    .nav-links {
        margin-top: 15px;
    }
    .nav-links li {
        margin: 0 10px;
    }
}