/* Base Styles */
:root {
    --primary-color: #003366;
    --accent-color: #FFB81C;
    --text-color: #333;
    --background-color: #fff;
    --header-height: 70px;
    --container-width: 1200px;
}

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
}

/* Accessibility */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary-color);
    color: white;
    padding: 8px;
    z-index: 100;
    transition: top 0.3s;
}

.skip-link:focus {
    top: 0;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

/* Container */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.site-header {
    background-color: var(--primary-color);
    color: white;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--header-height);
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.main-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

.logo img {
    height: 40px;
    width: auto;
}

/* Navigation */
.nav-menu {
    display: flex;
    list-style: none;
    gap: 20px;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    padding: 8px 12px;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.nav-menu a:hover,
.nav-menu a:focus {
    background-color: rgba(255,255,255,0.1);
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

/* Main Content */
main {
    margin-top: var(--header-height);
    min-height: calc(100vh - var(--header-height));
    padding: 40px 0;
}

/* Footer */
.site-footer {
    background-color: var(--primary-color);
    color: white;
    padding: 40px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 20px;
}

.footer-section h3 {
    margin-bottom: 15px;
    color: var(--accent-color);
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    color: white;
    font-size: 1.5rem;
    transition: color 0.3s;
}

.social-links a:hover {
    color: var(--accent-color);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

/* Responsive Design */
@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: var(--header-height);
        left: 0;
        right: 0;
        background-color: var(--primary-color);
        flex-direction: column;
        padding: 20px;
        gap: 10px;
    }

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

    .nav-menu li {
        width: 100%;
    }

    .nav-menu a {
        display: block;
        padding: 10px;
    }
}

/* Speaker Cards */
.speaker-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    padding: 20px 0;
}

.speaker-card {
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

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

.speaker-image {
    width: 100%;
    height: 300px;
    object-fit: cover;
}

.speaker-info {
    padding: 20px;
}

.speaker-name {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.speaker-title {
    color: var(--accent-color);
    font-weight: 500;
    margin-bottom: 15px;
}

.speaker-bio {
    font-size: 0.9rem;
    color: #666;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mb-20 {
    margin-bottom: 20px;
}

.mt-20 {
    margin-top: 20px;
}

/* Print Styles */
@media print {
    .site-header,
    .site-footer,
    .mobile-menu-toggle {
        display: none;
    }

    main {
        margin-top: 0;
    }

    body {
        font-size: 12pt;
    }

    a {
        text-decoration: none;
        color: black;
    }
}