:root {
    --bg: #f4efe6;
    --text: #1a1a1a;
    --accent: #0046d5;
    --accent-light: #e8eefb;
    --accent-teal: #0b8a78;
    --accent-teal-light: #e2f4f0;
    --accent-amber: #b7791f;
    --accent-amber-light: #f8eed9;
    --border: #e2e0dc;
    --secondary: #5c5c5c;
    --surface: #ffffff;
}

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

body {
    font-family: 'DM Sans', sans-serif;
    background:
        radial-gradient(900px 500px at 12% 0%, rgba(0, 70, 213, 0.08), transparent 55%),
        radial-gradient(700px 420px at 100% 14%, rgba(11, 138, 120, 0.07), transparent 45%),
        linear-gradient(180deg, rgba(255, 255, 255, 0.28), rgba(255, 255, 255, 0)),
        var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
}

/* ── Language Toggle ── */
.lang-switcher {
    position: fixed;
    top: 24px;
    right: 32px;
    z-index: 100;
}

.toggle-btn {
    background: var(--text);
    color: var(--bg);
    border: none;
    padding: 7px 14px;
    font-family: 'DM Mono', monospace;
    font-size: 0.78rem;
    cursor: pointer;
    border-radius: 6px;
    display: flex;
    align-items: center;
    gap: 7px;
    transition: transform 0.2s, opacity 0.2s;
}

.toggle-btn:hover {
    opacity: 0.85;
    transform: translateY(-1px);
}

/* ── Layout ── */
.container {
    max-width: 860px;
    margin: 0 auto;
    padding: 0 32px;
}

/* ── Hero ── */
header {
    padding: 100px 0 48px;
}

.hero-grid {
    display: grid;
    grid-template-columns: 1fr 220px;
    gap: 48px;
    align-items: center;
}

.hero-text .mono {
    font-family: 'DM Mono', monospace;
    color: var(--accent);
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 16px;
    display: block;
}

h1 {
    font-size: clamp(3rem, 8vw, 4.8rem);
    font-weight: 700;
    letter-spacing: -2.5px;
    line-height: 0.95;
    margin-bottom: 20px;
}

.hero-sub {
    font-size: 1.2rem;
    color: var(--secondary);
    max-width: 520px;
    font-weight: 300;
    line-height: 1.7;
}

.hero-sub strong {
    font-weight: 600;
    color: var(--text);
}

.hero-link {
    color: var(--text);
    border-bottom: 1px solid var(--border);
}

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

.hero-link strong {
    transition: color 0.2s;
}

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

.hero-advisor {
    font-size: 0.88rem;
    color: var(--secondary);
    margin-top: 12px;
}

.hero-affiliations {
    display: flex;
    gap: 28px;
    align-items: center;
    margin-top: 36px;
}

.affiliation-link {
    display: inline-flex;
    border-bottom: none;
}

.affiliation-link:hover {
    border-bottom-color: transparent;
}

.affiliation-logo {
    height: 46px;
    width: auto;
    opacity: 1;
    filter: none;
    transition: all 0.3s ease;
}

.affiliation-logo:hover {
    opacity: 1;
    filter: none;
}

.hero-photo {
    width: 220px;
    height: 275px;
    border-radius: 12px;
    overflow: hidden;
    background: linear-gradient(135deg, var(--accent-light) 0%, #d5dff0 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.hero-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

/* ── Sections ── */
section {
    padding: 60px 0;
    border-top: 1px solid var(--border);
}

h2 {
    font-family: 'DM Mono', monospace;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--accent);
    margin-bottom: 36px;
}

/* ── Research List ── */
.research-list {
    display: flex;
    flex-direction: column;
    gap: 0;
}

.research-item {
    display: grid;
    grid-template-columns: 170px 1fr;
    gap: 28px;
    padding: 22px 0;
    border-top: 1px solid var(--border);
}

.research-item:last-child {
    border-bottom: 1px solid var(--border);
}

.research-item-meta {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.research-title {
    font-weight: 600;
    font-size: 1.1rem;
    letter-spacing: -0.2px;
}

.research-item-body p {
    font-size: 0.92rem;
    color: var(--secondary);
    line-height: 1.65;
}

.research-item-body {
    max-width: 560px;
}

.research-item--blue .research-title {
    color: var(--accent);
}

.research-item--teal .research-title {
    color: var(--accent-teal);
}

.research-item--amber .research-title {
    color: var(--accent-amber);
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
    margin-top: 10px;
}

.tag {
    font-family: 'DM Mono', monospace;
    font-size: 0.72rem;
    color: var(--accent);
    background: var(--accent-light);
    padding: 3px 10px;
    border-radius: 4px;
    display: inline-block;
}

.research-item--teal .tag {
    color: var(--accent-teal);
    background: var(--accent-teal-light);
}

.research-item--amber .tag {
    color: var(--accent-amber);
    background: var(--accent-amber-light);
}

/* ── Publications ── */
.pub-item {
    margin-bottom: 36px;
    padding-left: 20px;
    border-left: 3px solid var(--accent-light);
}

.pub-item:last-child {
    margin-bottom: 0;
}

.pub-badge {
    font-family: 'DM Mono', monospace;
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--accent);
    background: var(--accent-light);
    padding: 2px 8px;
    border-radius: 3px;
    display: inline-block;
    margin-bottom: 8px;
}

.pub-title {
    font-size: 1.15rem;
    font-weight: 600;
    display: block;
    margin-bottom: 6px;
    line-height: 1.4;
}

.pub-meta {
    font-size: 0.88rem;
    color: var(--secondary);
    line-height: 1.5;
}

.pub-meta strong {
    color: var(--text);
    font-weight: 500;
}

.pub-links {
    margin-top: 8px;
    display: flex;
    gap: 16px;
}

.pub-links a {
    font-family: 'DM Mono', monospace;
    font-size: 0.78rem;
}

/* ── Contact ── */
.contact-email {
    font-size: 1.5rem;
    font-weight: 300;
    letter-spacing: -0.5px;
}

.contact-links {
    margin-top: 12px;
    display: flex;
    gap: 20px;
    font-size: 0.95rem;
}

.contact-links span {
    color: var(--border);
}

/* ── Footer ── */
footer {
    padding: 48px 0;
    font-size: 0.78rem;
    color: var(--secondary);
    border-top: 1px solid var(--border);
}

/* ── Links ── */
a {
    color: var(--accent);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: border-color 0.2s;
}

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

/* ── Multi-language ── */
.lang-es {
    display: none;
}

body.es .lang-en {
    display: none;
}

body.es .lang-es {
    display: block;
}

body.es .research-item .lang-es {
    display: block;
}

body.es .tags .lang-es,
body.es .pub-links .lang-es,
body.es span.lang-es {
    display: inline-block;
}

/* ── Responsive ── */
@media (max-width: 768px) {
    .hero-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .hero-photo {
        width: 160px;
        height: 200px;
        order: -1;
    }

    .research-item {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    h1 {
        font-size: 3rem;
        letter-spacing: -1.5px;
    }

    .container {
        margin-left: 0;
        margin-right: 0;
        padding: 0 24px;
    }

    header {
        padding: 80px 0 36px;
    }

    .hero-affiliations {
        flex-wrap: wrap;
    }
}

/* ── Fade-in animation ── */
@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-text,
.hero-photo {
    animation: fadeUp 0.6s ease-out both;
}

.hero-photo {
    animation-delay: 0.15s;
}

.hero-affiliations {
    animation: fadeUp 0.6s ease-out 0.3s both;
}

.teaching-content p {
    font-size: 0.95rem;
    line-height: 1.65;
    max-width: 680px;
}

.teaching-content .tags {
    margin-top: 20px;
}

.teaching-content .tag {
    background: var(--surface);
    border: 1px solid var(--border);
    color: var(--text);
}