/* Base styling */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #f4f4f9;
    margin: 0;
    padding: 0;
    color: #333;
}

/* Header */
header {
    background: #004080;
    color: white;
    padding: 1rem 2rem;
    text-align: center;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

nav {
    margin-top: 0.5rem;
}

nav a {
    margin: 0 1rem;
    color: white;
    text-decoration: none;
    font-weight: bold;
    transition: color 0.3s ease;
}

nav a:hover {
    text-decoration: underline;
    color: #a2d2ff;
}

/* Main Content */
main {
    padding: 2rem 1rem;
    max-width: 1200px;
    margin: auto;
}

h2 {
    color: #004080;
    margin-bottom: 0.5rem;
}

p {
    font-size: 1rem;
    margin-bottom: 1.5rem;
}

/* Lab Cards Container */
.lab-container {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    justify-content: center;
}

/* Individual Experiment Card */
.experiment-card {
    background: white;
    border: 1px solid #ccc;
    padding: 1rem;
    border-radius: 12px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    width: 260px;
    text-align: center;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

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

.experiment-card h3 {
    margin-top: 0;
    color: #002b5c;
}

.experiment-card p {
    font-size: 0.95rem;
    color: #555;
}

.button-group {
    margin-top: 0.75rem;
}

.button-group button {
    background: #004080;
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s ease;
}

.button-group button:hover {
    background: #0059b3;
}

/* Footer */
footer {
    background: #004080;
    color: white;
    text-align: center;
    padding: 1rem;
    margin-top: 3rem;
    font-size: 0.9rem;
}