@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
    --primary-color: #1a365d;
    --primary-light: #2b6cb0;
    --secondary-color: #319795;
    --accent-color: #38b2ac;
    --bg-color: #f7fafc;
    --text-color: #2d3748;
    --text-light: #4a5568;
    --white: #ffffff;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius: 8px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header & Navigation */
header {
    background-color: var(--white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo span {
    color: var(--secondary-color);
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
    padding-bottom: 5px;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: 0;
    left: 0;
    background-color: var(--secondary-color);
    transition: var(--transition);
}

.nav-links a:hover::after, .nav-links a.active::after {
    width: 100%;
}

/* Dropdown Menu */
.nav-links li {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--white);
    box-shadow: var(--shadow-md);
    border-radius: var(--radius);
    list-style: none;
    padding: 0.5rem 0;
    min-width: 220px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: var(--transition);
    z-index: 1000;
    border: 1px solid var(--border-color);
}

.nav-links li:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

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

.dropdown-menu a {
    padding: 0.6rem 1.2rem;
    display: block;
    color: var(--text-color) !important;
    font-weight: 400 !important;
    font-size: 0.85rem !important;
    transition: background 0.2s;
    text-decoration: none;
}

.dropdown-menu a:hover {
    background-color: var(--bg-color);
    color: var(--primary-light) !important;
}

.dropdown-menu a::after {
    display: none !important;
}

/* Main Layout */
main {
    flex: 1;
}

section {
    padding: 5rem 2rem;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

.page-header {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 4rem 2rem;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.page-header p {
    font-size: 1.2rem;
    color: #e2e8f0;
    max-width: 800px;
    margin: 0 auto;
}

/* Hero Section */
.hero {
    position: relative;
    min-height: 80vh;
    display: flex;
    align-items: center;
    background-color: var(--primary-color);
    color: var(--white);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.3;
    z-index: 0;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
    padding: 0 2rem;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    color: #e2e8f0;
}

.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

.btn-primary {
    background-color: var(--secondary-color);
    color: var(--white);
    box-shadow: 0 4px 14px 0 rgba(49, 151, 149, 0.39);
}

.btn-primary:hover {
    background-color: var(--accent-color);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(49, 151, 149, 0.4);
}

/* Cards & Grids */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.card-icon {
    font-size: 2.5rem;
    color: var(--secondary-color);
    margin-bottom: 1.5rem;
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.card p {
    color: var(--text-light);
}

/* Members Grid specifically for images */
.members-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.member-card {
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.member-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.member-img-container {
    width: 100%;
    height: 250px;
    background-color: #ebf8ff;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.member-img-container img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.member-info {
    padding: 1.5rem;
    text-align: center;
}

.member-name {
    font-size: 1.25rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.member-role {
    color: var(--secondary-color);
    font-weight: 500;
    margin-bottom: 1rem;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

.social-links a {
    color: var(--text-light);
    transition: var(--transition);
}

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

/* Publications List */
.publication-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.publication-item {
    background: var(--white);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--secondary-color);
    transition: var(--transition);
}

.publication-item:hover {
    box-shadow: var(--shadow-md);
}

.pub-title {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.pub-authors {
    color: var(--text-color);
    font-style: italic;
    margin-bottom: 0.5rem;
}

.pub-details {
    color: var(--text-light);
    font-size: 0.9rem;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    align-items: center;
}

.pub-tag {
    background-color: #e6fffa;
    color: var(--secondary-color);
    padding: 0.2rem 0.8rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

/* Content blocks */
.content-block {
    background: var(--white);
    padding: 3rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    margin-bottom: 2rem;
}

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

/* Footer */
footer {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 3rem 2rem 1rem;
    margin-top: auto;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 2rem;
}

.footer-col h4 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.footer-col p, .footer-col ul {
    color: #cbd5e0;
}

.footer-col ul {
    list-style: none;
}

.footer-col ul li {
    margin-bottom: 0.5rem;
}

.footer-col ul a {
    color: #cbd5e0;
    text-decoration: none;
    transition: var(--transition);
}

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

.footer-bottom {
    max-width: 1200px;
    margin: 2rem auto 0;
    padding-top: 1rem;
    border-top: 1px solid #4a5568;
    text-align: center;
    color: #a0aec0;
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-links {
        gap: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .content-block {
        padding: 1.5rem;
    }
}