:root {
    --primary: #1b4d3b;
    --primary-light: #2c6e54;
    --primary-dark: #12382b;
    --accent: #d97736;
    --bg-page: #f8faf9;
    --bg-card: #ffffff;
    --bg-alt: #eef4f1;
    --text-main: #1e2924;
    --text-muted: #52635b;
    --border: #dbe5e0;
    --shadow: 0 4px 20px rgba(18, 56, 43, 0.06);
    --radius: 12px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
    background-color: var(--bg-page);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1140px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    background-color: var(--bg-card);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    color: var(--primary-dark);
    font-weight: 700;
    font-size: 1.25rem;
}

.logo-icon {
    font-size: 1.5rem;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 24px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.2s ease;
}

.nav-links a:hover {
    color: var(--primary);
}

.nav-badge {
    background-color: var(--bg-alt);
    color: var(--primary) !important;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.85rem !important;
    border: 1px solid var(--border);
}

/* Hero */
.hero {
    padding: 64px 0;
    background: linear-gradient(180deg, var(--bg-card) 0%, var(--bg-page) 100%);
    border-bottom: 1px solid var(--border);
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 48px;
    align-items: center;
}

.tag {
    display: inline-block;
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--primary);
    background-color: var(--bg-alt);
    padding: 4px 12px;
    border-radius: 6px;
    margin-bottom: 16px;
}

.hero-title {
    font-size: 2.6rem;
    line-height: 1.2;
    color: var(--primary-dark);
    margin-bottom: 20px;
    font-weight: 800;
}

.hero-description {
    font-size: 1.15rem;
    color: var(--text-muted);
    margin-bottom: 32px;
}

.hero-actions {
    display: flex;
    gap: 16px;
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    font-size: 1rem;
    transition: all 0.2s ease;
}

.btn-primary {
    background-color: var(--primary);
    color: #ffffff;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background-color: var(--bg-alt);
}

.nature-svg {
    width: 100%;
    height: auto;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

/* Sections */
.section {
    padding: 72px 0;
}

.section-alt {
    background-color: var(--bg-alt);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto 48px auto;
}

.section-header h2 {
    font-size: 2rem;
    color: var(--primary-dark);
    margin-bottom: 12px;
}

.section-header p {
    color: var(--text-muted);
    font-size: 1.05rem;
}

/* Cards */
.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
}

.card {
    background-color: var(--bg-card);
    border-radius: var(--radius);
    padding: 32px;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(18, 56, 43, 0.1);
}

.card-icon {
    font-size: 2.2rem;
    margin-bottom: 16px;
}

.card h3 {
    font-size: 1.3rem;
    color: var(--primary-dark);
    margin-bottom: 12px;
}

.card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 20px;
}

.card-meta {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--primary);
    background-color: var(--bg-alt);
    padding: 4px 10px;
    border-radius: 4px;
}

/* Research */
.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
}

.research-item {
    background-color: var(--bg-card);
    padding: 24px;
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.research-item h4 {
    color: var(--primary-dark);
    font-size: 1.15rem;
    margin-bottom: 8px;
}

.research-item p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* About */
.about-container {
    max-width: 720px;
    text-align: center;
}

.about-container h2 {
    color: var(--primary-dark);
    font-size: 1.8rem;
    margin-bottom: 16px;
}

.about-container p {
    color: var(--text-muted);
    font-size: 1.05rem;
}

/* Footer */
.footer {
    background-color: var(--primary-dark);
    color: #c9ded5;
    padding: 36px 0;
}

.footer-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.9rem;
}

.footer-links {
    display: flex;
    gap: 20px;
}

.footer-links a {
    color: #c9ded5;
    text-decoration: none;
}

.footer-links a:hover {
    color: #ffffff;
}

/* Responsive */
@media (max-width: 840px) {
    .hero-grid {
        grid-template-columns: 1fr;
        gap: 36px;
    }
    .hero-title {
        font-size: 2.1rem;
    }
    .nav-links a:not(.nav-badge) {
        display: none;
    }
    .footer-container {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}