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

:root {
    --primary: #2c3e50;
    --primary-light: #34495e;
    --accent: #16a085;
    --accent-hover: #1abc9c;
    --background: #f8f9fa;
    --surface: #ffffff;
    --text: #2c3e50;
    --text-light: #5a6c7d;
    --text-muted: #7f8c8d;
    --border: #e0e4e8;
    --shadow: rgba(44, 62, 80, 0.08);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Lato', sans-serif;
    background: var(--background);
    min-height: 100vh;
    color: var(--text);
    line-height: 1.6;
}

/* Navigation Bar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--primary);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
    z-index: 1000;
}

.nav-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 60px;
}

.nav-logo {
    font-size: 1.4rem;
    font-weight: 700;
    color: #ffffff;
    text-decoration: none;
    letter-spacing: -0.5px;
    transition: color 0.3s ease;
}

.nav-logo:hover {
    color: var(--accent-hover);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 6px;
}

.nav-links li a {
    display: block;
    padding: 8px 18px;
    text-decoration: none;
    color: rgba(255, 255, 255, 0.85);
    font-weight: 400;
    font-size: 0.95rem;
    border-radius: 6px;
    transition: all 0.2s ease;
}

.nav-links li a:hover {
    background: rgba(255, 255, 255, 0.15);
    color: #ffffff;
}

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

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: #ffffff;
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* Mobile Navigation Styles */
@media (max-width: 600px) {
    .nav-toggle {
        display: flex;
    }

    .nav-links {
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        flex-direction: column;
        background: rgba(255, 255, 255, 0.99);
        padding: 15px 20px;
        gap: 5px;
        box-shadow: 0 10px 30px var(--shadow);
        border-bottom: 1px solid var(--border);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }

    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav-links li a {
        padding: 12px 20px;
        text-align: center;
    }
}

/* Container */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 90px 20px 40px;
}

/* Profile Section */
.profile-section {
    background: var(--surface);
    border-radius: 12px;
    padding: 50px 40px;
    text-align: center;
    box-shadow: 0 2px 12px var(--shadow);
    margin-bottom: 24px;
    scroll-margin-top: 80px;
    border: 1px solid var(--border);
}

.profile-image {
    width: 170px;
    height: 170px;
    border-radius: 50%;
    object-fit: cover;
    border: 4px solid var(--border);
    margin-bottom: 24px;
    box-shadow: 0 4px 20px var(--shadow);
}

.name {
    font-size: 2.4rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.bio {
    max-width: 620px;
    margin: 0 auto 24px;
    color: var(--text-light);
    font-size: 1.05rem;
}

.bio p {
    margin-bottom: 14px;
}

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

.bio a:hover {
    color: var(--accent-hover);
    text-decoration: underline;
}

.contact {
    margin-bottom: 24px;
}

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

/* Links/Buttons */
.links {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.link-button {
    display: inline-block;
    padding: 10px 22px;
    background: var(--primary);
    color: white;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.2s ease;
}

.link-button:hover {
    background: var(--accent);
    transform: translateY(-1px);
}

/* Publications Section */
.publications-section {
    background: var(--surface);
    border-radius: 12px;
    padding: 40px;
    box-shadow: 0 2px 12px var(--shadow);
    margin-bottom: 24px;
    scroll-margin-top: 80px;
    border: 1px solid var(--border);
}

.section-title {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 28px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--accent);
    display: inline-block;
}

.publications-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* Publication Item */
.publication {
    padding: 20px;
    background: var(--background);
    border-radius: 8px;
    border-left: 3px solid var(--accent);
    transition: all 0.2s ease;
}

.publication:hover {
    transform: translateX(4px);
    box-shadow: 0 4px 16px var(--shadow);
}

.pub-title {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 8px;
    line-height: 1.4;
}

.pub-title a {
    color: var(--primary);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

.pub-authors {
    font-size: 0.92rem;
    color: var(--text-light);
    margin-bottom: 6px;
}

.pub-venue {
    font-size: 0.88rem;
    color: var(--text-muted);
    font-style: italic;
}

.pub-year {
    display: inline-block;
    padding: 3px 10px;
    background: var(--accent);
    color: white;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 500;
    margin-top: 10px;
}

.pub-links {
    margin-top: 12px;
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.pub-link {
    font-size: 0.85rem;
    color: var(--accent);
    text-decoration: none;
    padding: 4px 12px;
    border: 1px solid var(--accent);
    border-radius: 4px;
    transition: all 0.2s ease;
}

.pub-link:hover {
    background: var(--accent);
    color: white;
}

.pub-meta {
    font-size: 0.82rem;
    color: var(--text-muted);
    margin-top: 8px;
}

/* Loading State */
.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-muted);
}

.spinner {
    width: 36px;
    height: 36px;
    border: 3px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    margin: 0 auto 15px;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Talks Section */
.talks-section {
    background: var(--surface);
    border-radius: 12px;
    padding: 40px;
    box-shadow: 0 2px 12px var(--shadow);
    margin-bottom: 24px;
    scroll-margin-top: 80px;
    border: 1px solid var(--border);
}

.talks-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.talk-item {
    display: flex;
    align-items: flex-start;
    gap: 18px;
    padding: 18px 20px;
    background: var(--background);
    border-radius: 8px;
    border-left: 3px solid var(--primary-light);
    transition: all 0.2s ease;
}

.talk-item:hover {
    transform: translateX(4px);
    box-shadow: 0 4px 16px var(--shadow);
}

.talk-date {
    flex-shrink: 0;
    padding: 6px 14px;
    background: var(--primary);
    color: white;
    border-radius: 4px;
    font-size: 0.82rem;
    font-weight: 500;
    white-space: nowrap;
}

.talk-content {
    flex: 1;
}

.talk-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 4px;
}

.talk-venue {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-style: italic;
}

/* Responsive Talks */
@media (max-width: 500px) {
    .talk-item {
        flex-direction: column;
        gap: 10px;
    }

    .talk-date {
        align-self: flex-start;
    }
}

/* Footer */
.footer {
    text-align: center;
    padding: 30px;
    color: var(--text-muted);
    font-size: 0.88rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 80px 15px 30px;
    }

    .profile-section,
    .publications-section,
    .talks-section {
        padding: 30px 20px;
    }

    .name {
        font-size: 2rem;
    }

    .profile-image {
        width: 140px;
        height: 140px;
    }

    .section-title {
        font-size: 1.4rem;
    }
}

@media (max-width: 480px) {
    .links {
        flex-direction: column;
        align-items: center;
    }

    .link-button {
        width: 100%;
        max-width: 200px;
        text-align: center;
    }

    .name {
        font-size: 1.7rem;
    }

    .bio {
        font-size: 0.98rem;
    }
}