:root {
    --primary-color: #2563eb;
    --secondary-color: #3b82f6;
    --accent-color: #60a5fa;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
}

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

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
nav {
    background: var(--bg-white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.nav-brand {
    font-family: 'Poppins', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

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

.nav-menu a {
    color: var(--text-dark);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

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

.nav-menu a.active {
    color: var(--primary-color);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s;
}

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

/* Hero Section */
.hero {
    padding: 4rem 0;
    background: var(--bg-white);
    margin-top: 2rem;
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
}

.hero-content {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 3rem;
    align-items: start;
}

.profile-image-wrapper {
    position: relative;
}

.profile-image {
    width: 100%;
    border-radius: 20px;
    box-shadow: var(--shadow-md);
}

.profile-info h1 {
    font-family: 'Poppins', sans-serif;
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.profile-info .title {
    color: var(--primary-color);
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

.profile-info .affiliation {
    color: var(--text-light);
    margin-bottom: 2rem;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-light);
    border-radius: 50%;
    color: var(--text-dark);
    text-decoration: none;
    transition: all 0.3s;
}

.social-links a:hover {
    background: var(--primary-color);
    color: white;
    transform: translateY(-3px);
}

/* Section Styles */
.section {
    margin: 2rem 0;
    padding: 3rem;
    background: var(--bg-white);
    border-radius: 20px;
    box-shadow: var(--shadow-md);
    animation: fadeIn 0.6s ease-out;
}

.section-title {
    font-family: 'Poppins', sans-serif;
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--text-dark);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.section-title i {
    color: var(--primary-color);
    font-size: 1.5rem;
}

/* Description Section */
.description {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-dark);
}

.description a {
    color: var(--primary-color);
    text-decoration: none;
}

.description a:hover {
    text-decoration: underline;
}

.research-interests {
    margin-top: 2rem;
}

.research-interests h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.research-interests ul {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
}

.research-interests li {
    padding: 0.8rem 1rem;
    background: var(--bg-light);
    border-left: 3px solid var(--primary-color);
    border-radius: 5px;
    transition: all 0.3s;
}

.research-interests li:hover {
    background: #e0e7ff;
    transform: translateX(5px);
}

.research-interests li i {
    margin-right: 0.5rem;
    color: var(--primary-color);
}

/* News Section */
.news-list {
    list-style: none;
    position: relative;
    padding-left: 30px;
}

.news-list::before {
    content: '';
    position: absolute;
    left: 8px;
    top: 10px;
    bottom: 10px;
    width: 2px;
    background: var(--border-color);
}

.news-item {
    position: relative;
    margin-bottom: 1.5rem;
    padding: 1rem;
    background: var(--bg-light);
    border-radius: 10px;
    transition: all 0.3s;
}

.news-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-sm);
}

.news-item::before {
    content: '';
    position: absolute;
    left: -22px;
    top: 50%;
    transform: translateY(-50%);
    width: 12px;
    height: 12px;
    background: var(--primary-color);
    border-radius: 50%;
    border: 2px solid white;
}

.news-date {
    color: var(--primary-color);
    font-weight: 600;
    margin-right: 1rem;
}

/* Publications Section */
.pub-item {
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: var(--bg-light);
    border-radius: 10px;
    transition: all 0.3s;
}

.pub-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.pub-venue {
    display: inline-block;
    padding: 0.3rem 0.8rem;
    background: var(--primary-color);
    color: white;
    border-radius: 5px;
    font-weight: 600;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.pub-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

.pub-title a {
    color: inherit;
    text-decoration: none;
}

.pub-title a:hover {
    color: var(--primary-color);
}

.pub-authors {
    color: var(--text-light);
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.pub-authors strong {
    color: var(--primary-color);
    font-weight: 600;
}

.pub-links {
    display: flex;
    gap: 1rem;
    margin-top: 0.5rem;
}

.pub-links a {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    padding: 0.3rem 0.8rem;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    color: var(--text-dark);
    text-decoration: none;
    font-size: 0.9rem;
    transition: all 0.3s;
}

.pub-links a:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.pub-links a i {
    font-size: 0.9rem;
}

/* Footer */
footer {
    margin-top: 4rem;
    padding: 2rem 0;
    text-align: center;
    color: var(--text-light);
    background: var(--bg-white);
    border-radius: 20px 20px 0 0;
}

footer a {
    color: var(--primary-color);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* Mobile Menu Toggle (hidden by default) */
.menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.menu-toggle span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    margin: 3px 0;
    transition: 0.3s;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .profile-image-wrapper {
        max-width: 250px;
        margin: 0 auto;
    }

    .social-links {
        justify-content: center;
    }

    .nav-container {
        flex-wrap: wrap;
    }

    .nav-menu {
        width: 100%;
        flex-direction: column;
        gap: 1rem;
        margin-top: 1rem;
        display: none;
    }

    .nav-menu.active {
        display: flex;
    }

    .menu-toggle {
        display: flex;
    }

    .section {
        padding: 2rem 1rem;
    }

    .research-interests ul {
        grid-template-columns: 1fr;
    }

    .profile-info h1 {
        font-size: 2rem;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .pub-links {
        flex-wrap: wrap;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero {
        padding: 2rem 1rem;
    }

    .profile-info h1 {
        font-size: 1.75rem;
    }

    .section-title {
        font-size: 1.25rem;
    }

    .pub-item {
        padding: 1rem;
    }

    .news-item {
        padding: 0.75rem;
    }
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Print Styles */
@media print {
    nav, footer {
        display: none;
    }

    .section {
        box-shadow: none;
        break-inside: avoid;
    }

    body {
        background: white;
    }
}