/* ============================================================
   VARIABLES
   ============================================================ */
:root {
    --bg: #FDFAF3;
    --bg-alt: #F5F0E5;
    --text: #1C1A17;
    --text-light: #6B5E4A;
    --gold: #B8860B;
    --gold-hover: #8B6010;
    --green: #2D4A2D;
    --border: #E4D9C5;
    --card-bg: #FFFFFF;
    --shadow: rgba(28, 26, 23, 0.08);
    --shadow-hover: rgba(28, 26, 23, 0.16);
    --nav-height: 68px;
    --max-width: 940px;
    --max-width-narrow: 680px;
}

/* ============================================================
   RESET & BASE
   ============================================================ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Lora', Georgia, serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

/* Paper grain texture overlay */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    opacity: 0.032;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='300' height='300' filter='url(%23noise)'/%3E%3C/svg%3E");
    background-repeat: repeat;
    background-size: 300px 300px;
}

/* Side terrain decorations */
.side-topo {
    display: none;
    position: fixed;
    top: 0;
    bottom: 0;
    width: 220px;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.side-topo-left  { left: 0; }
.side-topo-right { right: 0; transform: scaleX(-1); }

.side-topo svg {
    width: 100%;
    height: 100%;
}

@media (min-width: 1280px) {
    .side-topo { display: block; }
}

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

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

/* ============================================================
   NAVIGATION
   ============================================================ */
#navbar {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 100;
    height: var(--nav-height);
    transition: background 0.35s ease, box-shadow 0.35s ease, border-color 0.35s ease;
    border-bottom: 2px solid transparent;
}

#navbar.scrolled {
    background: var(--bg);
    border-bottom-color: var(--gold);
    box-shadow: 0 2px 24px var(--shadow);
}

.nav-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-family: 'Playfair Display', Georgia, serif;
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text);
    letter-spacing: 0.01em;
    transition: color 0.2s ease;
}
.nav-logo:hover { color: var(--gold-hover); }

.nav-links {
    display: flex;
    list-style: none;
    gap: 0.1rem;
    align-items: center;
}

.nav-link {
    font-family: 'Inter', sans-serif;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-light);
    padding: 0.4rem 0.8rem;
    position: relative;
    transition: color 0.2s ease;
    letter-spacing: 0.02em;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--gold);
    transition: width 0.25s ease;
    border-radius: 1px;
}

.nav-link:hover,
.nav-link.active {
    color: var(--text);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: calc(100% - 1.6rem);
}

.nav-cv {
    font-family: 'Inter', sans-serif;
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.07em;
    text-transform: uppercase;
    color: white;
    background: var(--gold-hover);
    padding: 0.42rem 1rem;
    border-radius: 4px;
    margin-left: 0.6rem;
    transition: background 0.2s ease, transform 0.2s ease;
}
.nav-cv:hover {
    background: var(--gold);
    color: white;
    transform: translateY(-1px);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text);
    border-radius: 1px;
    transition: transform 0.3s ease, opacity 0.3s ease;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   HERO
   ============================================================ */
#hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: calc(var(--nav-height) + 3rem) 2rem 5rem;
    overflow: hidden;
    background-color: var(--bg);
}

.topo-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
    pointer-events: none;
}

.topo-bg svg {
    width: 100%;
    height: 100%;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 720px;
}

.hero-label {
    font-family: 'Inter', sans-serif;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--gold-hover);
    margin-bottom: 1.25rem;
    opacity: 0;
    animation: fadeUp 0.7s ease forwards 0.2s;
}

.hero-name {
    font-family: 'Playfair Display', Georgia, serif;
    font-size: clamp(3.5rem, 10vw, 6.5rem);
    font-weight: 700;
    color: var(--text);
    line-height: 1.05;
    letter-spacing: -0.02em;
    margin-bottom: 1rem;
    opacity: 0;
    animation: fadeUp 0.7s ease forwards 0.35s;
}

.hero-affiliation {
    font-family: 'Lora', serif;
    font-size: 1.1rem;
    font-style: italic;
    color: var(--text-light);
    margin-bottom: 0.5rem;
    opacity: 0;
    animation: fadeUp 0.7s ease forwards 0.5s;
}

.hero-tagline {
    font-family: 'Inter', sans-serif;
    font-size: 0.8rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--text-light);
    margin-bottom: 2.75rem;
    opacity: 0;
    animation: fadeUp 0.7s ease forwards 0.62s;
}

.hero-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 2.25rem;
    flex-wrap: wrap;
    opacity: 0;
    animation: fadeUp 0.7s ease forwards 0.75s;
}

.hero-socials {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    opacity: 0;
    animation: fadeUp 0.7s ease forwards 0.9s;
}

.hero-socials a {
    color: var(--text-light);
    display: flex;
    align-items: center;
    transition: color 0.2s ease, transform 0.2s ease;
}
.hero-socials a:hover {
    color: var(--gold-hover);
    transform: translateY(-2px);
}

/* Scroll caret */
.scroll-indicator {
    position: absolute;
    bottom: 2.25rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
    color: var(--text-light);
    opacity: 0;
    animation: fadeIn 0.7s ease forwards 1.2s;
    display: flex;
    align-items: center;
}

.scroll-indicator svg {
    animation: bounce 2.2s ease-in-out infinite 1.9s;
}

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
    display: inline-block;
    font-family: 'Inter', sans-serif;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    padding: 0.72rem 1.6rem;
    border-radius: 4px;
    transition: all 0.22s ease;
    cursor: pointer;
    border: none;
    white-space: nowrap;
}

.btn-primary {
    background: var(--gold-hover);
    color: white;
}
.btn-primary:hover {
    background: var(--gold);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 5px 16px rgba(139, 96, 16, 0.32);
}

.btn-secondary {
    background: transparent;
    color: var(--text);
    border: 1.5px solid var(--border);
}
.btn-secondary:hover {
    border-color: var(--gold-hover);
    color: var(--gold-hover);
    transform: translateY(-2px);
}

.btn-outline {
    display: inline-block;
    background: transparent;
    color: var(--gold-hover);
    border: 1.5px solid var(--gold-hover);
    font-family: 'Inter', sans-serif;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    padding: 0.65rem 1.4rem;
    border-radius: 4px;
    transition: all 0.22s ease;
    margin-top: 1.75rem;
}
.btn-outline:hover {
    background: var(--gold-hover);
    color: white;
    transform: translateY(-2px);
}

/* ============================================================
   SECTIONS
   ============================================================ */
.section {
    padding: 6.5rem 2rem;
}

.section-alt {
    background-color: var(--bg-alt);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
}

.container-narrow {
    max-width: var(--max-width-narrow);
    margin: 0 auto;
    text-align: center;
}

.section-label {
    display: inline-block;
    font-family: 'Inter', sans-serif;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--gold-hover);
    margin-bottom: 0.5rem;
}

h2 {
    font-family: 'Playfair Display', Georgia, serif;
    font-size: clamp(2rem, 4vw, 2.75rem);
    font-weight: 600;
    color: var(--text);
    line-height: 1.2;
    margin-bottom: 2.75rem;
    letter-spacing: -0.01em;
}

/* ============================================================
   ABOUT
   ============================================================ */
.about-grid {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 4.5rem;
    align-items: start;
}

.about-photo img {
    width: 100%;
    border-radius: 4px;
    border: 3px solid var(--gold);
    box-shadow: 0 8px 30px var(--shadow);
    transition: box-shadow 0.3s ease;
}
.about-photo img:hover {
    box-shadow: 0 12px 40px var(--shadow-hover);
}

.about-text h2 {
    margin-bottom: 1.5rem;
}

.about-text p {
    color: var(--text);
    margin-bottom: 1.25rem;
    font-size: 1rem;
    line-height: 1.85;
}

.about-text a {
    color: var(--gold-hover);
    border-bottom: 1px solid rgba(139, 96, 16, 0.3);
    transition: border-color 0.2s ease, color 0.2s ease;
}
.about-text a:hover {
    border-bottom-color: var(--gold);
    color: var(--gold);
}

/* ============================================================
   PAPERS
   ============================================================ */
.papers {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.paper-card {
    background: var(--card-bg);
    border-left: 4px solid var(--gold);
    border-radius: 0 6px 6px 0;
    padding: 1.75rem 2rem;
    box-shadow: 0 2px 14px var(--shadow);
    transition: box-shadow 0.25s ease, transform 0.25s ease;
}

.paper-card:hover {
    box-shadow: 0 8px 28px var(--shadow-hover);
    transform: translateY(-3px);
}

.paper-meta {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.8rem;
}

.paper-tag {
    font-family: 'Inter', sans-serif;
    font-size: 0.67rem;
    font-weight: 700;
    letter-spacing: 0.13em;
    text-transform: uppercase;
    color: var(--gold-hover);
    background: rgba(184, 134, 11, 0.1);
    padding: 0.2rem 0.6rem;
    border-radius: 3px;
}

.paper-date {
    font-family: 'Inter', sans-serif;
    font-size: 0.78rem;
    color: var(--text-light);
}

.paper-title {
    font-family: 'Playfair Display', Georgia, serif;
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text);
    line-height: 1.45;
    margin-bottom: 0;
}

.paper-abstract {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.45s ease, margin-top 0.3s ease;
}

.paper-abstract.open {
    max-height: 800px;
    margin-top: 1.1rem;
}

.paper-abstract p {
    font-size: 0.91rem;
    color: var(--text-light);
    line-height: 1.8;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

.paper-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-top: 1.25rem;
}

.btn-paper {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-family: 'Inter', sans-serif;
    font-size: 0.77rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: white;
    background: var(--green);
    padding: 0.42rem 0.9rem;
    border-radius: 3px;
    transition: background 0.2s ease, transform 0.2s ease;
}
.btn-paper:hover {
    background: #1e331e;
    color: white;
    transform: translateY(-1px);
}

.btn-abstract-toggle {
    background: none;
    border: none;
    cursor: pointer;
    font-family: 'Inter', sans-serif;
    font-size: 0.78rem;
    font-weight: 500;
    color: var(--text-light);
    padding: 0;
    transition: color 0.2s ease;
}
.btn-abstract-toggle:hover { color: var(--gold-hover); }

/* ============================================================
   NEWS
   ============================================================ */
.news-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.news-card {
    display: flex;
    flex-direction: column;
    background: var(--card-bg);
    border-radius: 6px;
    padding: 1.75rem;
    box-shadow: 0 2px 14px var(--shadow);
    border-top: 3px solid var(--gold);
    transition: box-shadow 0.25s ease, transform 0.25s ease;
    color: var(--text);
}

.news-card:hover {
    box-shadow: 0 8px 28px var(--shadow-hover);
    transform: translateY(-3px);
    color: var(--text);
}

.news-source {
    font-family: 'Inter', sans-serif;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--gold-hover);
    margin-bottom: 0.2rem;
}

.news-date {
    font-family: 'Inter', sans-serif;
    font-size: 0.77rem;
    color: var(--text-light);
    margin-bottom: 0.9rem;
}

.news-title {
    font-family: 'Playfair Display', Georgia, serif;
    font-size: 1.05rem;
    font-weight: 600;
    line-height: 1.45;
    margin-bottom: 0.75rem;
    color: var(--text);
    flex-grow: 1;
}

.news-excerpt {
    font-size: 0.875rem;
    color: var(--text-light);
    line-height: 1.7;
    margin-bottom: 1.1rem;
}

.news-read {
    font-family: 'Inter', sans-serif;
    font-size: 0.77rem;
    font-weight: 700;
    color: var(--gold-hover);
    letter-spacing: 0.03em;
    transition: color 0.2s ease, transform 0.2s ease;
    display: inline-block;
}

.news-card:hover .news-read {
    color: var(--gold);
    transform: translateX(3px);
}

/* ============================================================
   CONTACT
   ============================================================ */
.contact-intro {
    font-size: 1.05rem;
    color: var(--text-light);
    margin-bottom: 2.25rem;
    font-style: italic;
}

.contact-links {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    align-items: center;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: 0.65rem;
    font-family: 'Inter', sans-serif;
    font-size: 0.92rem;
    color: var(--text);
    padding: 0.65rem 1.25rem;
    border-radius: 4px;
    border: 1.5px solid var(--border);
    width: 100%;
    max-width: 340px;
    transition: all 0.22s ease;
}

.contact-link:hover {
    border-color: var(--gold-hover);
    color: var(--gold-hover);
    transform: translateX(5px);
    background: rgba(139, 96, 16, 0.04);
}

/* ============================================================
   FOOTER
   ============================================================ */
footer {
    background: var(--bg-alt);
    border-top: 1px solid var(--border);
    padding: 2rem;
    text-align: center;
}

footer p {
    font-family: 'Inter', sans-serif;
    font-size: 0.78rem;
    color: var(--text-light);
    letter-spacing: 0.04em;
}

/* ============================================================
   SCROLL ANIMATIONS
   ============================================================ */
.animate-fade-up {
    opacity: 0;
    transform: translateY(22px);
    transition: opacity 0.65s ease, transform 0.65s ease;
}

.animate-fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================================
   KEYFRAMES
   ============================================================ */
@keyframes fadeUp {
    from { opacity: 0; transform: translateY(18px); }
    to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to   { opacity: 1; }
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50%       { transform: translateY(7px); }
}

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

    .nav-links {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--bg);
        flex-direction: column;
        padding: 1rem 0 1.5rem;
        border-bottom: 2px solid var(--gold);
        box-shadow: 0 6px 24px var(--shadow);
        gap: 0;
        align-items: flex-start;
    }

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

    .nav-link {
        padding: 0.8rem 2rem;
        width: 100%;
    }

    .nav-cv {
        margin: 0.6rem 2rem 0;
        align-self: flex-start;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .about-photo {
        max-width: 180px;
    }

    .news-grid {
        grid-template-columns: 1fr;
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

    .section { padding: 4.5rem 1.5rem; }
    h2 { margin-bottom: 2rem; }
}

@media (max-width: 480px) {
    .about-photo { max-width: 150px; }
    .paper-card { padding: 1.25rem 1.25rem; }
    .news-card { padding: 1.25rem; }
}