:root {
    --accent: #E77500; 
    --dark-blue: #0f172a;
    --slate-50: #f8fafc;
    --slate-100: #f1f5f9;
    --slate-200: #e2e8f0;
    --slate-300: #cbd5e1;
    --slate-400: #94a3b8;
    --slate-500: #64748b;
    --slate-600: #475569;
    --link-blue: #0066cc;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: #ffffff;
    color: var(--dark-blue);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    scroll-behavior: smooth;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2.5rem;
}

/* --- Navigation --- */
nav {
    padding: 2.5rem 0;
    background: #fff;
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.nav-logo {
    font-family: 'Playfair Display', serif;
    font-weight: 700;
    font-size: 1.4rem;
    text-decoration: none;
    color: var(--dark-blue);
    letter-spacing: -0.01em;
    text-transform: uppercase;
}

.nav-links {
    display: flex;
    gap: 2.5rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--slate-600);
    font-size: 0.95rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    transition: var(--transition);
}

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

/* --- Hero Section --- */
.hero {
    padding: 40px 0 60px;
    display: flex;
    align-items: center;
    gap: 5rem;
}

.hero-content {
    flex: 1;
}

.hero-title {
    font-family: 'Playfair Display', serif;
    font-size: 4.5rem;
    line-height: 1.1;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--dark-blue);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--slate-600);
    margin-bottom: 2.5rem;
    font-weight: 400;
    line-height: 1.5;
}

.hero-image-container {
    flex-shrink: 0;
}

.headshot {
    width: 280px;
    height: 280px;
    border-radius: 12px;
    object-fit: cover;
    background: var(--slate-50);
}

/* --- Buttons --- */
.social-buttons {
    display: flex;
    gap: 0.75rem;
    align-items: center;
    flex-wrap: wrap;
}

.btn {
    height: 44px;
    padding: 0 1.25rem;
    border-radius: 10px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    white-space: nowrap;
}

.btn-dark {
    background: #111827;
    color: white;
}

.btn-dark:hover {
    background: #1f2937;
}

.btn-white {
    background: white;
    color: #475569;
    border: 1px solid var(--slate-200);
}

.btn-white:hover {
    border-color: var(--slate-400);
    background: var(--slate-50);
}

/* --- Dropdown Menu --- */
.contact-dropdown {
    position: relative;
    display: inline-block;
}

.dropdown-menu {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    background: white;
    border: 1px solid var(--slate-200);
    border-radius: 12px;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
    min-width: 240px;
    z-index: 50;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: var(--transition);
    padding: 8px;
}

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

.dropdown-item {
    display: flex;
    flex-direction: column;
    padding: 10px 14px;
    border-radius: 8px;
    text-decoration: none;
    transition: var(--transition);
}

.dropdown-item:hover {
    background: var(--slate-50);
}

.dropdown-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 700;
    color: var(--slate-400);
    letter-spacing: 0.05em;
    margin-bottom: 2px;
}

.dropdown-email {
    font-size: 0.95rem;
    color: var(--dark-blue);
    font-weight: 500;
}

/* --- Section Styling --- */
.section-block {
    margin-bottom: 80px;
}

.section-header {
    font-family: 'Playfair Display', serif;
    font-size: 2.75rem;
    margin-bottom: 1rem;
    color: var(--dark-blue);
    font-weight: 700;
}

.divider-full {
    width: 100%;
    height: 1px;
    background: var(--slate-100);
    margin-bottom: 40px;
}

.bio-text {
    font-size: 1.15rem;
    color: var(--slate-600);
    line-height: 1.7;
}

.bio-text p {
    margin-bottom: 1.5rem;
}

.inline-link {
    color: var(--link-blue);
    text-decoration: none;
    border-bottom: 1px solid var(--slate-200);
    transition: var(--transition);
}

.inline-link:hover {
    border-bottom-color: var(--link-blue);
    color: var(--accent);
}

/* --- Research Items --- */
.pub-category {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--slate-500);
    font-weight: 800;
    margin: 60px 0 30px;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.pub-category::before {
    content: "";
    width: 4px;
    height: 20px;
    background: var(--accent);
    display: inline-block;
}

.pub-item {
    margin-bottom: 3rem;
}

.pub-title-container {
    display: block;
    text-decoration: none;
    color: inherit;
}

.pub-title {
    font-size: 1.35rem;
    color: var(--dark-blue);
    font-weight: 600;
    margin-bottom: 0.4rem;
    line-height: 1.3;
    transition: var(--transition);
}

.pub-title-container:hover .pub-title {
    color: var(--link-blue);
    text-decoration: underline;
    text-decoration-thickness: 1.5px;
    text-underline-offset: 4px;
}

.pub-citation {
    font-size: 1.1rem;
    color: var(--slate-600);
    margin-bottom: 1rem;
    line-height: 1.5;
}

.pub-actions {
    display: flex;
    gap: 1.5rem;
    align-items: center;
}

.action-link {
    font-size: 0.9rem;
    color: var(--link-blue);
    text-decoration: none;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    transition: var(--transition);
    cursor: pointer;
    user-select: none;
}

.action-link:hover {
    color: var(--accent);
}

.action-link i {
    font-size: 0.8rem;
    transition: var(--transition);
}

/* Animated Abstract Container */
.abstract-wrapper {
    display: grid;
    grid-template-rows: 0fr;
    transition: grid-template-rows 0.3s ease-out;
    overflow: hidden;
}

.pub-item.active .abstract-wrapper {
    grid-template-rows: 1fr;
}

.pub-item.active .abstract-trigger i {
    transform: rotate(180deg);
}

.abstract-content {
    min-height: 0;
}

.abstract-text {
    margin-top: 1.25rem;
    font-size: 1.05rem;
    color: var(--slate-600);
    line-height: 1.7;
    padding: 1.5rem;
    background: var(--slate-50);
    border-radius: 8px;
    border-left: 3px solid var(--slate-200);
}

/* --- Footer --- */
footer {
    margin-top: 80px;
    padding: 60px 0;
    border-top: 1px solid var(--slate-100);
    color: var(--slate-500);
    font-size: 1rem;
}

@media (max-width: 900px) {
    .hero {
        flex-direction: column-reverse;
        gap: 3rem;
        text-align: center;
    }
    .hero-title {
        font-size: 3.5rem;
    }
    .social-buttons {
        justify-content: center;
    }
}