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

:root {
    --primary-color: #ced2d7;
    --secondary-color: rgb(4, 39, 70);
    --text-color: #7a7676;
    --light-gray: #f8f9fa;
    --border-color: #e0e0e0;
    --hover-color: #2980b9;
    --text-gray: #555;
    --blue-top: rgb(20, 75, 110);
    --gray-side: rgb(83, 83, 83);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #fff;
    padding-top: 60px; /* Space for fixed header */
}

/* Top Banner Navigation */
.top-banner {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: var(--blue-top);
    border-bottom: 2px solid var(--border-color);
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    justify-content: flex-start;
    padding: 0 30px;
}

.top-banner .gamma-logo {
    margin: 0;
    margin-right: 100px;
}

.top-banner .gamma-logo img {
    height: 50px;
    width: auto;
    opacity: 0.9;
    transition: opacity 0.3s;
}

.top-banner .gamma-logo img:hover {
    opacity: 1;
}

.top-banner .nav-menu {
    margin: 0;
    padding: 0;
    margin-left: 30px;
}

.top-banner .nav-menu ul {
    list-style: none;
    display: flex;
    justify-content: flex-start;
    align-items: center;
    margin: 0;
    padding: 0;
}

.top-banner .nav-menu li {
    margin: 0;
}

.top-banner .nav-menu a {
    display: block;
    padding: 18px 25px;
    color: var(--primary-color);
    text-decoration: none;
    transition: all 0.3s;
    font-weight: 500;
    font-size: 0.95rem;
}

.top-banner .nav-menu a:hover,
.top-banner .nav-menu a.active {
    background-color: rgba(255, 255, 255, 0.1);
    color: #fff;
}

.container {
    display: flex;
    min-height: calc(100vh - 60px);
}

/* Sidebar Styles */
.sidebar {
    width: 320px;
    background-color: var(--gray-side);
    border-right: 1px solid var(--border-color);
    padding: 40px 30px;
    position: fixed;
    top: 60px; /* Below the banner */
    height: calc(100vh - 60px);
    overflow-y: auto;
}

.profile {
    text-align: center;
    margin-bottom: 30px;
}

.profile-photo {
    width: 230px;
    height: 280px;
    border-radius: 50%;
    object-fit: cover;
    margin-bottom: 20px;
    border: 4px solid #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.profile h1 {
    font-size: 1.8rem;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.profile h3 {
    font-size: 1.3rem;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.profile .title {
    font-size: 1rem;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.profile .affiliation {
    font-size: 0.9rem;
    color: var(--primary-color);
    margin: 3px 0;
    line-height: 1.4;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-top: 20px;
}

.social-links a {
    color: var(--primary-color);
    font-size: 1.5rem;
    transition: color 0.3s;
}

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

/* Main Content */
.main-content {
    margin-left: 320px;
    flex: 1;
    padding: 60px 80px;
    max-width: 1200px;
}

.main-content h2 {
    font-size: 2.0rem;
    color: var(--secondary-color);
    margin-bottom: 30px;
    padding-bottom: 15px;
    border-bottom: 3px solid var(--secondary-color);
}

.main-content h3 {
    font-size: 1.5rem;
    color: var(--secondary-color);
    margin-top: 30px;
    margin-bottom: 15px;
}

.about-content p {
    margin-bottom: 20px;
    font-size: 1.05rem;
    text-align: justify;
}

.main-content a {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 500;
}

.main-content a:hover {
    text-decoration: underline;
}

/* Research Interests */
.research-interests {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
    margin: 20px 0;
}

.research-interests li {
    background-color: var(--light-gray);
    padding: 12px 20px;
    border-left: 4px solid var(--secondary-color);
    border-radius: 3px;
}

/* News List */
.news-list {
    list-style: none;
    margin: 20px 0;
}

.news-list li {
    padding: 15px 0;
    border-bottom: 1px solid var(--border-color);
}

.news-list li:last-child {
    border-bottom: none;
}

.news-list .date {
    color: var(--secondary-color);
    font-weight: 600;
}

/* Publication Items */
.publication-item {
    margin-bottom: 30px;
    padding: 20px;
    background-color: var(--light-gray);
    border-radius: 5px;
    border-left: 4px solid var(--secondary-color);
}

.publication-item h3 {
    margin-top: 0;
    font-size: 1.2rem;
}

.publication-item .authors {
    color: #666;
    font-style: italic;
    margin: 10px 0;
}

.publication-item .venue {
    color: var(--secondary-color);
    font-weight: 600;
}

.publication-item .links {
    margin-top: 10px;
}

.publication-item .links a {
    color: var(--secondary-color);
    text-decoration: none;
    margin-right: 15px;
    font-weight: 500;
}

.publication-item .links a:hover {
    text-decoration: underline;
}

/* Footer */
footer {
    background-color: var(--primary-color);
    color: #fff;
    text-align: center;
    padding: 20px;
    margin-left: 320px;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .sidebar {
        width: 280px;
    }
    
    .main-content {
        margin-left: 280px;
        padding: 40px 50px;
    }
    
    footer {
        margin-left: 280px;
    }
}

@media (max-width: 768px) {
    .container {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
        position: relative;
        height: auto;
        padding: 30px 20px;
    }
    
    .main-content {
        margin-left: 0;
        padding: 30px 20px;
    }
    
    footer {
        margin-left: 0;
    }
    
    .profile-photo {
        width: 150px;
        height: 150px;
    }
    
    .main-content h2 {
        font-size: 2rem;
    }
}