:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --light-color: #ecf0f1;
    --dark-color: #34495e;
    --text-color: #333;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #f9f9f9;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
.navbar {
    background: var(--primary-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--box-shadow);
}

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

.logo {
    color: white;
    font-size: 1.5rem;
    font-weight: bold;
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    transition: background-color 0.3s;
}

.nav-link:hover,
.nav-link.active {
    background-color: var(--secondary-color);
}

/* Header */
header {
    background: linear-gradient(rgba(44, 62, 80, 0.7), rgba(52, 73, 94, 0.7)),
        url('../images/header-bg.jpg') center/cover no-repeat;
    color: white;
    padding: 3rem 0;
    text-align: center;
    margin-bottom: 2rem;
    position: relative;
}

/* Alternative without gradient overlay */
.header-plain {
    background: url('../images/header-bg.jpg') center/cover no-repeat;
    color: white;
    padding: 3rem 0;
    text-align: center;
    margin-bottom: 2rem;
    position: relative;
}

/* For dark text on light background images */
.header-light {
    background: url('../images/header-bg-light.jpg') center/cover no-repeat;
    color: #333;
    padding: 3rem 0;
    text-align: center;
    margin-bottom: 2rem;
    position: relative;
}

/* Add a dark overlay for better text readability */
.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    /* Dark overlay */
    z-index: 1;
}

.header>.container {
    position: relative;
    z-index: 2;
    /* Ensure text appears above the overlay */
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
    margin-bottom: 1.5rem;
}

.badges {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

/* Main Content */
main {
    flex: 1;
    padding-bottom: 2rem;
}

section {
    background: white;
    border-radius: var(--border-radius);
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--box-shadow);
}

h2 {
    color: var(--primary-color);
    border-bottom: 2px solid var(--secondary-color);
    padding-bottom: 0.5rem;
    margin-bottom: 1.5rem;
}

h3 {
    color: var(--dark-color);
    margin: 1.5rem 0 1rem;
}

p {
    margin-bottom: 1rem;
}

ul,
ol {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

li {
    margin-bottom: 0.5rem;
}

code {
    background-color: var(--light-color);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
}

pre {
    background-color: var(--light-color);
    padding: 1rem;
    border-radius: var(--border-radius);
    overflow-x: auto;
    margin: 1rem 0;
}

.btn {
    display: inline-block;
    background-color: var(--secondary-color);
    color: white;
    padding: 0.7rem 1.5rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: bold;
    transition: background-color 0.3s;
    margin: 0.5rem;
}

.btn:hover {
    background-color: #2980b9;
}

.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.team-member {
    background-color: var(--light-color);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    text-align: center;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
}

th,
td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

th {
    background-color: var(--light-color);
    color: var(--primary-color);
}

footer {
    background-color: var(--dark-color);
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: auto;
}

.math-block {
    overflow-x: auto;
    margin: 1.5rem 0;
    padding: 1rem;
    background-color: #f8f9fa;
    border-radius: var(--border-radius);
}

.home-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.card {
    background: white;
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    text-align: center;
    transition: transform 0.3s;
}

.card:hover {
    transform: translateY(-5px);
}

.card h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* Mobile Navigation */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

@media (max-width: 768px) {
    .nav-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--primary-color);
        flex-direction: column;
        padding: 1rem;
    }

    .nav-menu.active {
        display: flex;
    }

    h1 {
        font-size: 2rem;
    }

    section {
        padding: 1.5rem;
    }

    .team-grid {
        grid-template-columns: 1fr;
    }

    .home-grid {
        grid-template-columns: 1fr;
    }
}