:root {
    --bg-color: #ffffff;
    --text-color: #1c1c1c;
    --text-muted: #555555;
    --border-color: #e3e3e3;
    --accent-color: #1f6feb;
    --accent-dark: #0f4fb3;
    --card-bg: rgba(255, 255, 255, 0.92);
    --nav-bg: rgba(255, 255, 255, 0.95);
    --shadow-color: rgba(15, 23, 42, 0.08);
}

[data-theme="dark"] {
    --bg-color: #0f1115;
    --text-color: #e5e7eb;
    --text-muted: #9ca3af;
    --border-color: #1f2933;
    --accent-color: #7dd3fc;
    --accent-dark: #38bdf8;
    --card-bg: rgba(15, 17, 21, 0.9);
    --nav-bg: rgba(15, 17, 21, 0.92);
    --shadow-color: rgba(0, 0, 0, 0.35);
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Nunito', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    margin: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.7;
    transition: background-color 0.3s ease, color 0.3s ease;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--accent-dark);
}

img {
    max-width: 100%;
    display: block;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--nav-bg);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(12px);
    z-index: 1000;
    box-shadow: 0 4px 10px var(--shadow-color);
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1.5rem;
}

.brand {
    font-weight: 700;
    font-size: 1.1rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-color);
}

.nav-links {
    list-style: none;
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin: 0;
    padding: 0;
}

.nav-link {
    color: var(--text-color);
    font-size: 0.95rem;
    letter-spacing: 0.03em;
    text-transform: uppercase;
}

.nav-link.active {
    color: var(--accent-color);
    font-weight: 600;
}

.theme-toggle,
.nav-toggle {
    border: none;
    background: transparent;
    color: var(--text-color);
    cursor: pointer;
    padding: 0.35rem;
    border-radius: 4px;
    transition: color 0.2s ease, background 0.2s ease;
}

.theme-toggle:hover,
.nav-toggle:hover {
    color: var(--accent-color);
    background: rgba(31, 111, 235, 0.08);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 0.25rem;
}

.nav-toggle span {
    width: 22px;
    height: 2px;
    background-color: var(--text-color);
    display: block;
    transition: transform 0.3s ease;
}

progress#progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    appearance: none;
    -webkit-appearance: none;
    z-index: 999;
}

progress#progress::-webkit-progress-bar {
    background: transparent;
}

progress#progress::-webkit-progress-value {
    background: var(--accent-color);
}

progress#progress::-moz-progress-bar {
    background: var(--accent-color);
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 6.5rem 1.5rem 3rem;
}

.post {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 24px;
    padding: 2rem 2.5rem;
    box-shadow: 0 20px 45px var(--shadow-color);
}

.about {
    display: grid;
    grid-template-columns: minmax(0, 2fr) minmax(220px, 1fr);
    gap: 3rem;
    align-items: start;
    margin-bottom: 2.5rem;
}

.post-title {
    font-size: 2.25rem;
    margin-bottom: 0.5rem;
    letter-spacing: 0.02em;
}

.about p {
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.profile img {
    border-radius: 18px;
    width: 100%;
    box-shadow: 0 18px 35px var(--shadow-color);
}

.contact-icons {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-top: 1rem;
    font-size: 1.4rem;
}

.contact-icons a {
    color: var(--text-color);
    width: 38px;
    height: 38px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease, color 0.2s ease;
}

.contact-icons a:hover {
    background: var(--accent-color);
    color: #ffffff;
    border-color: var(--accent-color);
}

.news {
    margin-bottom: 2.5rem;
}

.news h2,
.publications-section h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.pub-category {
    font-size: 1.15rem;
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: var(--text-color);
    font-weight: 600;
    letter-spacing: 0.03em;
    text-transform: uppercase;
}

.pub-category:first-of-type {
    margin-top: 0;
}

.news-list {
    list-style: none;
    padding: 0;
    margin: 0;
    border-left: 2px solid var(--border-color);
}

.news-list li {
    padding: 0.65rem 0 0.65rem 1rem;
    display: flex;
    gap: 0.5rem;
}

.news-date {
    font-weight: 600;
    color: var(--accent-color);
    min-width: 96px;
}

.news-text {
    color: var(--text-muted);
}

.bibliography {
    list-style: none;
    padding: 0;
    margin: 0;
}

.pub-row {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 1.5rem;
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

.pub-row:last-child {
    border-bottom: none;
}

.pub-abbr img,
.pub-abbr video,
.pub-abbr iframe {
    border-radius: 12px;
    object-fit: cover;
    width: 100%;
    height: 140px;
    box-shadow: 0 12px 30px var(--shadow-color);
    background-color: #eee;
}

.badge {
    display: inline-block;
    margin-top: 0.65rem;
    padding: 0.2rem 0.6rem;
    border-radius: 999px;
    font-size: 0.75rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    background: var(--accent-color);
    color: #ffffff;
}

.badge-preprint {
    background: #94a3b8;
}

.badge-highlight {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
}

.pub-title {
    margin: 0 0 0.4rem;
    font-size: 1.2rem;
}

.pub-authors {
    margin: 0 0 0.35rem;
    color: var(--text-muted);
}

.pub-venue {
    margin: 0 0 0.65rem;
    font-style: italic;
    color: var(--text-color);
}

.pub-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.btn {
    border: 1px solid var(--border-color);
    border-radius: 999px;
    padding: 0.2rem 0.9rem;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-color);
    transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.btn-sm {
    font-size: 0.78rem;
    padding: 0.2rem 0.75rem;
}

.btn:hover {
    background: var(--accent-color);
    color: #ffffff;
    border-color: var(--accent-color);
}

.footer {
    padding: 2rem 0 3rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

.footer a {
    color: var(--accent-color);
}

@media (max-width: 900px) {
    .about {
        grid-template-columns: 1fr;
    }

    .profile {
        max-width: 280px;
        justify-self: center;
    }

    .pub-row {
        grid-template-columns: 1fr;
    }

}

@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .nav-links {
        position: absolute;
        top: 100%;
        right: 0;
        flex-direction: column;
        align-items: flex-start;
        background: var(--nav-bg);
        border: 1px solid var(--border-color);
        border-radius: 12px;
        padding: 1rem;
        margin-top: 0.5rem;
        display: none;
        min-width: 200px;
    }

    .nav-links.open {
        display: flex;
    }

    .container {
        padding: 6rem 1rem 2rem;
    }

    .post {
        padding: 1.5rem;
    }
}

@media (max-width: 500px) {
    .post {
        padding: 1.25rem;
    }

    .news-date {
        min-width: 80px;
    }

    .btn {
        font-size: 0.8rem;
    }
}