:root {
    --primary-blue: #0f2c4a;
    --brand-blue: #145374;
    --brand-green: #228b55;
    --accent-green: #2ecc71;
    --bg-white: #ffffff;
    --bg-light: #f8fafc;
    --text-dark: #1e293b;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-white);
    color: var(--text-dark);
    line-height: 1.6;
}

/* Header & Navigation */
header {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.75rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-container {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo-container img {
    height: 48px;
    width: auto;
    display: block;
}

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

nav a {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 500;
    transition: color 0.2s ease;
}

nav a:hover, nav a.active {
    color: var(--brand-green);
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
    background: none;
    border: none;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--primary-blue);
    border-radius: 2px;
    transition: 0.3s;
}

/* Hero Sections */
.hero {
    position: relative;
    height: 70vh;
    min-height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
    background-size: cover;
    background-position: center;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(15, 44, 74, 0.85) 0%, rgba(34, 139, 85, 0.75) 100%);
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1rem;
    letter-spacing: -1px;
}

.hero-content p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.75rem;
    border-radius: 4px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s ease;
}

.btn-primary {
    background: linear-gradient(135deg, var(--brand-blue), var(--brand-green));
    color: white;
    box-shadow: 0 4px 14px rgba(34, 139, 85, 0.3);
}

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

/* Main Content Layout */
.container {
    max-width: 1000px;
    margin: 4rem auto;
    padding: 0 2rem;
}

h2 {
    font-size: 2.25rem;
    color: var(--primary-blue);
    margin-bottom: 1.5rem;
    letter-spacing: -0.5px;
}

p {
    margin-bottom: 1.25rem;
    font-size: 1.05rem;
    color: var(--text-dark);
}

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

.report-card {
    background: var(--bg-light);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 1.75rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.report-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
}

.report-tag {
    display: inline-block;
    background: var(--brand-blue);
    color: white;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    padding: 0.25rem 0.6rem;
    border-radius: 4px;
    margin-bottom: 0.75rem;
    letter-spacing: 0.5px;
}

.report-date {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.report-card h3 {
    font-size: 1.25rem;
    color: var(--primary-blue);
    margin-bottom: 0.75rem;
}

.featured-report {
    background: linear-gradient(135deg, rgba(20, 83, 116, 0.05), rgba(34, 139, 85, 0.08));
    border: 2px solid var(--brand-green);
    border-radius: 8px;
    padding: 2.5rem;
    margin-bottom: 3rem;
}

/* Footer */
footer {
    background: var(--bg-light);
    border-top: 1px solid var(--border-color);
    padding: 3rem 2rem 1.5rem;
    margin-top: 6rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 2rem;
}

.footer-links a {
    color: var(--text-muted);
    text-decoration: none;
    margin-left: 2rem;
    font-size: 0.95rem;
}

.footer-links a:hover {
    color: var(--brand-green);
}

.copyright {
    max-width: 1200px;
    margin: 1.5rem auto 0;
    text-align: center;
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* Responsive Styles for Mobile */
@media (max-width: 768px) {
    .menu-toggle {
        display: flex;
    }
    nav {
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: var(--bg-white);
        border-bottom: 1px solid var(--border-color);
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease-out;
    }
    nav.active {
        max-height: 300px;
    }
    nav ul {
        flex-direction: column;
        gap: 0;
        padding: 1rem 2rem;
    }
    nav ul li {
        padding: 0.5rem 0;
        border-bottom: 1px solid var(--bg-light);
    }
    .hero-content h1 {
        font-size: 2.1rem;
    }
    .hero-content p {
        font-size: 1.05rem;
    }
    .footer-content {
        flex-direction: column;
        align-items: flex-start;
    }
    .footer-links {
        margin-left: 0;
        display: flex;
        flex-direction: column;
        gap: 0.75rem;
    }
    .footer-links a {
        margin-left: 0;
    }
}