/* =====================================================
   SCHOOL OF SANDSTONE RESERVOIRS - MAIN STYLESHEET
   ===================================================== */

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

:root {
    --primary-blue: #003366;
    --white: #FFFFFF;
    --light-gray: #F5F5F5;
    --medium-gray: #666666;
    --dark-gray: #333333;
    --warm-beige: #E8DCC4;
    --accent-brown: #8B7355;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-size: 16px;
    line-height: 1.7;
    color: var(--dark-gray);
    background-color: var(--white);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--primary-blue);
    margin-bottom: 1rem;
}

h1 { font-size: 2.75rem; }
h2 { font-size: 2rem; margin-top: 2.5rem; }
h3 { font-size: 1.5rem; margin-top: 2rem; }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: 1.25rem;
    color: var(--dark-gray);
}

a {
    color: var(--primary-blue);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

ul, ol {
    margin-bottom: 1.25rem;
    padding-left: 1.5rem;
}

li {
    margin-bottom: 0.5rem;
}

strong {
    font-weight: 600;
}

/* Layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.container-narrow {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 2rem;
}

section {
    padding: 4rem 0;
}

section.gray-bg {
    background-color: var(--light-gray);
}

section.dark-bg {
    background-color: var(--primary-blue);
    color: var(--white);
}

section.dark-bg h1,
section.dark-bg h2,
section.dark-bg h3,
section.dark-bg p {
    color: var(--white);
}

/* Navigation */
.navbar {
    background-color: var(--primary-blue);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    color: var(--white);
    font-size: 1.25rem;
    font-weight: 600;
    text-decoration: none;
}

.nav-logo:hover {
    color: var(--warm-beige);
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    margin: 0;
    padding: 0;
}

.nav-menu a {
    color: var(--white);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 400;
    transition: color 0.3s ease;
}

.nav-menu a:hover {
    color: var(--warm-beige);
    text-decoration: none;
}

.nav-menu a.active {
    color: var(--warm-beige);
    font-weight: 600;
}

/* Mobile menu toggle */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--white);
    margin: 5px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-blue) 0%, #001a33 100%);
    color: var(--white);
    padding: 6rem 0;
    text-align: center;
}

.hero h1 {
    color: var(--white);
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero .subtitle {
    font-size: 1.35rem;
    font-style: italic;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.hero p {
    color: rgba(255,255,255,0.9);
    max-width: 800px;
    margin: 0 auto 2rem;
    font-size: 1.1rem;
}

/* Page Header (for non-home pages) */
.page-header {
    background: linear-gradient(135deg, var(--primary-blue) 0%, #001a33 100%);
    color: var(--white);
    padding: 4rem 0;
    text-align: center;
}

.page-header h1 {
    color: var(--white);
    margin-bottom: 0.5rem;
}

.page-header p {
    color: rgba(255,255,255,0.85);
    font-size: 1.1rem;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    border-radius: 6px;
    font-weight: 500;
    font-size: 1rem;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background-color: var(--primary-blue);
    color: var(--white);
}

.btn-primary:hover {
    background-color: #002244;
    color: var(--white);
    text-decoration: none;
}

.btn-secondary {
    background-color: var(--white);
    color: var(--primary-blue);
    border: 2px solid var(--primary-blue);
}

.btn-secondary:hover {
    background-color: var(--primary-blue);
    color: var(--white);
    text-decoration: none;
}

.btn-light {
    background-color: var(--white);
    color: var(--primary-blue);
}

.btn-light:hover {
    background-color: var(--light-gray);
    text-decoration: none;
}

.btn-group {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 2rem;
}

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

.feature-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 25px rgba(0,0,0,0.12);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

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

.feature-card p {
    color: var(--medium-gray);
    font-size: 0.95rem;
}

/* Stats Section */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}

.stat-item h3 {
    font-size: 2.5rem;
    color: var(--primary-blue);
    margin-bottom: 0.5rem;
}

.stat-item p {
    color: var(--medium-gray);
    font-size: 1rem;
}

.dark-bg .stat-item h3,
.dark-bg .stat-item p {
    color: var(--white);
}

/* Instructor Cards */
.instructor-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    margin-bottom: 2rem;
}

.instructor-card h3 {
    color: var(--primary-blue);
    margin-bottom: 0.25rem;
}

.instructor-card .affiliation {
    color: var(--medium-gray);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.instructor-card .role {
    color: var(--accent-brown);
    font-style: italic;
    margin-bottom: 1rem;
}

.instructor-card .bio {
    margin-bottom: 1rem;
}

.instructor-card .research-focus {
    background: var(--light-gray);
    padding: 1rem;
    border-radius: 6px;
    font-size: 0.9rem;
}

.instructor-card .research-focus strong {
    color: var(--primary-blue);
}

/* Content Sections */
.content-section {
    margin-bottom: 3rem;
}

.content-section h2 {
    border-bottom: 2px solid var(--primary-blue);
    padding-bottom: 0.5rem;
    margin-bottom: 1.5rem;
}

/* Image Placeholders */
.image-placeholder {
    background: var(--light-gray);
    border: 2px dashed var(--medium-gray);
    border-radius: 8px;
    padding: 3rem;
    text-align: center;
    color: var(--medium-gray);
    margin: 1.5rem 0;
}

/* Technical Content */
.technical-content {
    background: var(--light-gray);
    padding: 2rem;
    border-radius: 8px;
    margin: 1.5rem 0;
    border-left: 4px solid var(--primary-blue);
}

.technical-content h4 {
    color: var(--primary-blue);
    margin-bottom: 1rem;
}

/* Placeholder Pages */
.placeholder-content {
    text-align: center;
    padding: 4rem 2rem;
}

.placeholder-content h2 {
    border: none;
}

.placeholder-content .coming-soon {
    font-size: 1.25rem;
    color: var(--medium-gray);
    margin-bottom: 2rem;
}

/* Contact Form */
.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.contact-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
}

.contact-card h3 {
    color: var(--primary-blue);
    margin-bottom: 1rem;
    font-size: 1.25rem;
}

/* Footer */
.footer {
    background-color: var(--primary-blue);
    color: var(--white);
    padding: 3rem 0 1.5rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer h4 {
    color: var(--white);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.footer p, .footer a {
    color: rgba(255,255,255,0.8);
    font-size: 0.95rem;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(255,255,255,0.2);
    color: rgba(255,255,255,0.6);
    font-size: 0.9rem;
}

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

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

/* Responsive Design */
@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    h3 { font-size: 1.25rem; }
    
    .hero h1 { font-size: 2.25rem; }
    .hero .subtitle { font-size: 1.1rem; }
    
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--primary-blue);
        flex-direction: column;
        padding: 1rem;
        gap: 0.5rem;
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .nav-toggle {
        display: block;
    }
    
    .container, .container-narrow {
        padding: 0 1rem;
    }
    
    section {
        padding: 3rem 0;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .btn-group {
        flex-direction: column;
        align-items: center;
    }
}

/* Print Styles */
@media print {
    .navbar, .footer, .btn {
        display: none;
    }
    
    body {
        font-size: 12pt;
    }
    
    a {
        color: var(--dark-gray);
    }
}