/* ======================================
   SIGMAA EM Modern Stylesheet
   Environmental Mathematics Design
   ====================================== */

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

:root {
    /* Color Palette */
    --primary-green: #2d8659;
    --accent-teal: #4ecdc4;
    --dark-green: #1a5237;
    --light-green: #e8f5e9;
    --background: #f8f9fa;
    --text-dark: #2c3e50;
    --text-light: #6c757d;
    --white: #ffffff;
    --border-color: #dee2e6;

    /* Typography */
    --font-heading: 'Playfair Display', Georgia, serif;
    --font-body: 'Lato', 'Open Sans', sans-serif;
    --font-math: 'STIX Two Text', 'STIXGeneral', serif;

    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-xxl: 4rem;

    /* Layout */
    --max-width: 1200px;
    --nav-width: 250px;
    --header-height: 120px;

    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 25px rgba(0,0,0,0.15);

    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* Typography */
@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:wght@400;600;700&family=Lato:wght@300;400;700&display=swap');

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--background);
    min-height: 100vh;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    line-height: 1.3;
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: var(--spacing-sm);
}

a {
    color: var(--primary-green);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--accent-teal);
    text-decoration: underline;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* Header */
.header {
    background: linear-gradient(135deg, var(--primary-green) 0%, var(--dark-green) 100%);
    color: var(--white);
    padding: var(--spacing-md) var(--spacing-lg);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-content {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.header-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.maa-logo {
    height: 60px;
    width: auto;
}

.sigmaa-em-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.earth-logo {
    height: 55px;
    width: auto;
}

.sigmaa-em-text {
    font-family: 'Montserrat', sans-serif;
    font-weight: 700;
    color: var(--white);
    line-height: 1.1;
}

.sigmaa-em-text .sigmaa {
    display: block;
    font-size: 1.6rem;
    letter-spacing: -0.08em;
}

.sigmaa-em-text .em {
    display: block;
    font-size: 1.6rem;
    letter-spacing: -0.08em;
}

.site-title {
    flex: 1;
    text-align: right;
}

.site-title .subtitle {
    font-size: 1.05rem;
    font-family: 'Barlow Condensed', sans-serif;
    opacity: 0.95;
    font-weight: 500;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

/* Navigation */
.main-nav {
    background-color: var(--white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: var(--header-height);
    z-index: 999;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.nav-list {
    list-style: none;
    display: flex;
    gap: var(--spacing-xs);
    flex-wrap: wrap;
}

.nav-list li a {
    display: block;
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--text-dark);
    font-weight: 500;
    transition: all var(--transition-fast);
    border-bottom: 3px solid transparent;
}

.nav-list li a:hover,
.nav-list li a.active {
    color: var(--primary-green);
    background-color: var(--light-green);
    border-bottom-color: var(--primary-green);
    text-decoration: none;
}

/* Mobile Navigation Toggle */
.nav-toggle {
    display: none;
    background: var(--primary-green);
    color: var(--white);
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    cursor: pointer;
    font-size: 1.2rem;
    border-radius: 4px;
}

/* Hero Banner / Carousel */
.hero-banner {
    position: relative;
    width: 100%;
    height: 500px;
    overflow: hidden;
    background-color: var(--dark-green);
}

.carousel {
    position: relative;
    width: 100%;
    height: 100%;
}

.carousel-track {
    position: relative;
    height: 100%;
}

.carousel-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity var(--transition-slow);
}

.carousel-slide.active {
    opacity: 1;
}

.carousel-slide img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.carousel-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.8) 0%, transparent 100%);
    color: var(--white);
    padding: var(--spacing-xl) var(--spacing-lg);
}

.carousel-overlay h2 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--white);
}

.carousel-overlay p {
    font-size: 1.2rem;
    max-width: 600px;
}

.carousel-controls {
    position: absolute;
    bottom: var(--spacing-md);
    right: var(--spacing-lg);
    display: flex;
    gap: var(--spacing-sm);
    z-index: 10;
}

.carousel-btn {
    background: rgba(255,255,255,0.3);
    border: 2px solid var(--white);
    color: var(--white);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.carousel-btn:hover {
    background: var(--white);
    color: var(--primary-green);
}

.carousel-indicators {
    position: absolute;
    bottom: var(--spacing-md);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: var(--spacing-xs);
    z-index: 10;
}

.indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255,255,255,0.5);
    border: none;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.indicator.active {
    background: var(--white);
    transform: scale(1.3);
}

/* Main Content Layout */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg);
}

.content-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
}

/* Cards */
.card {
    background: var(--white);
    border-radius: 8px;
    box-shadow: var(--shadow-sm);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.card h3 {
    color: var(--primary-green);
    margin-bottom: var(--spacing-md);
}

/* Mission Section */
.mission-section {
    background: var(--white);
    padding: var(--spacing-xl);
    border-radius: 8px;
    box-shadow: var(--shadow-md);
    margin-bottom: var(--spacing-xl);
}

.mission-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.mission-item {
    padding: var(--spacing-md);
    border-left: 4px solid var(--primary-green);
    background: var(--light-green);
    border-radius: 0 8px 8px 0;
}

.mission-item h4 {
    color: var(--dark-green);
    margin-bottom: var(--spacing-sm);
}

/* Feature Highlights */
.feature-highlight {
    background: linear-gradient(135deg, var(--primary-green) 0%, var(--accent-teal) 100%);
    color: var(--white);
    padding: var(--spacing-xl);
    border-radius: 8px;
    text-align: center;
    margin: var(--spacing-xl) 0;
}

.feature-highlight h2 {
    color: var(--white);
    font-size: 2rem;
    margin-bottom: var(--spacing-md);
}

.feature-highlight .btn {
    background: var(--white);
    color: var(--primary-green);
}

.feature-highlight .btn:hover {
    background: var(--light-green);
    transform: scale(1.05);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--primary-green);
    color: var(--white);
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    transition: all var(--transition-fast);
    text-align: center;
}

.btn:hover {
    background: var(--dark-green);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    text-decoration: none;
    color: var(--white);
}

.btn-secondary {
    background: var(--accent-teal);
}

.btn-secondary:hover {
    background: #3db3aa;
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary-green);
    color: var(--primary-green);
}

.btn-outline:hover {
    background: var(--primary-green);
    color: var(--white);
}

/* Gallery Grid */
.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.gallery-item {
    position: relative;
    overflow: hidden;
    border-radius: 8px;
    box-shadow: var(--shadow-sm);
    cursor: pointer;
    transition: all var(--transition-normal);
    background: var(--white);
}

.gallery-item:hover {
    transform: scale(1.03);
    box-shadow: var(--shadow-lg);
}

.gallery-item img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    transition: transform var(--transition-normal);
}

.gallery-item:hover img {
    transform: scale(1.1);
}

.gallery-caption {
    padding: var(--spacing-sm);
    background: var(--white);
    text-align: center;
}

.gallery-caption h4 {
    font-size: 1rem;
    color: var(--text-dark);
    margin: 0;
}

/* Officers Grid */
.officers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.officer-card {
    text-align: center;
    padding: var(--spacing-lg);
}

.officer-card h4 {
    color: var(--primary-green);
    margin-bottom: var(--spacing-xs);
}

.officer-card .role {
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: var(--spacing-xs);
}

.officer-card .affiliation {
    color: var(--text-light);
    font-size: 0.9rem;
}

/* Activities List */
.activities-list {
    list-style: none;
}

.activity-item {
    background: var(--white);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    border-radius: 8px;
    border-left: 4px solid var(--accent-teal);
    box-shadow: var(--shadow-sm);
}

.activity-item h3 {
    color: var(--primary-green);
    margin-bottom: var(--spacing-sm);
}

.activity-meta {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-sm);
}

/* Footer */
.footer {
    background: var(--dark-green);
    color: var(--white);
    padding: var(--spacing-xl) var(--spacing-lg);
    margin-top: var(--spacing-xxl);
}

.footer-content {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.footer-section h4 {
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.footer-section a {
    color: var(--light-green);
    display: block;
    margin-bottom: var(--spacing-xs);
}

.footer-section a:hover {
    color: var(--white);
}

.footer-bottom {
    text-align: center;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255,255,255,0.2);
    font-size: 0.9rem;
    opacity: 0.8;
}

/* Utility Classes */
.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }

/* Responsive Design */
@media (max-width: 768px) {
    :root {
        --spacing-xl: 2rem;
        --spacing-xxl: 3rem;
    }

    h1 { font-size: 2rem; }
    h2 { font-size: 1.75rem; }
    h3 { font-size: 1.35rem; }

    .header-content {
        flex-direction: column;
        text-align: center;
    }

    .site-title h1 {
        font-size: 1.5rem;
    }

    .nav-toggle {
        display: block;
        margin: var(--spacing-sm) auto;
    }

    .nav-list {
        display: none;
        flex-direction: column;
        width: 100%;
    }

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

    .nav-list li a {
        padding: var(--spacing-md);
        border-bottom: 1px solid var(--border-color);
    }

    .hero-banner {
        height: 350px;
    }

    .carousel-overlay h2 {
        font-size: 1.75rem;
    }

    .carousel-overlay p {
        font-size: 1rem;
    }

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

    .gallery-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }

    .container {
        padding: var(--spacing-lg) var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .hero-banner {
        height: 250px;
    }

    .carousel-overlay {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .carousel-overlay h2 {
        font-size: 1.5rem;
    }

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

/* Print Styles */
@media print {
    .header,
    .main-nav,
    .nav-toggle,
    .carousel-controls,
    .carousel-indicators,
    .footer {
        display: none;
    }

    body {
        background: white;
    }
}