/* ============================================
   GEOSPATIAL RESEARCH - STYLESHEET
   Refined Academic Aesthetic
   ============================================ */

:root {
    /* Colors - Sophisticated dark palette */
    --color-bg: #0a0a0b;
    --color-bg-elevated: #111113;
    --color-bg-card: #161618;
    --color-border: rgba(255, 255, 255, 0.08);
    --color-border-hover: rgba(255, 255, 255, 0.15);
    
    --color-text-primary: #f4f4f5;
    --color-text-secondary: #a1a1aa;
    --color-text-tertiary: #71717a;
    
    --color-accent: #c9a962;
    --color-accent-dim: rgba(201, 169, 98, 0.15);
    
    /* Typography */
    --font-display: 'Cormorant Garamond', Georgia, serif;
    --font-body: 'DM Sans', -apple-system, sans-serif;
    
    /* Spacing */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2.5rem;
    --space-xl: 4rem;
    --space-2xl: 6rem;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;
}

/* ============================================
   RESET & BASE
   ============================================ */

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

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

body {
    font-family: var(--font-body);
    font-weight: 300;
    line-height: 1.6;
    color: var(--color-text-primary);
    background-color: var(--color-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: inherit;
    text-decoration: none;
}

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

/* ============================================
   NAVIGATION
   ============================================ */

.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: var(--space-sm) var(--space-lg);
    background: rgba(10, 10, 11, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
}

.logo-mark {
    font-size: 1.5rem;
    color: var(--color-accent);
}

.logo-text {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 500;
    letter-spacing: 0.02em;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-lg);
}

.nav-link {
    font-size: 0.875rem;
    font-weight: 400;
    color: var(--color-text-secondary);
    letter-spacing: 0.03em;
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--color-accent);
    transition: width var(--transition-base);
}

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

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

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

.nav-toggle span {
    width: 24px;
    height: 1.5px;
    background: var(--color-text-primary);
    transition: var(--transition-fast);
}

/* ============================================
   MAIN CONTENT
   ============================================ */

.main {
    padding-top: 80px;
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
    min-height: calc(100vh - 80px);
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: center;
    gap: var(--space-xl);
    padding: var(--space-2xl) var(--space-lg);
    max-width: 1400px;
    margin: 0 auto;
}

.hero-content {
    animation: fadeInUp 0.8s ease forwards;
}

.hero-eyebrow {
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: var(--space-md);
}

.hero-title {
    font-family: var(--font-display);
    font-size: clamp(2.5rem, 5vw, 4.5rem);
    font-weight: 400;
    line-height: 1.1;
    margin-bottom: var(--space-md);
}

.hero-title em {
    font-style: italic;
    color: var(--color-accent);
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    max-width: 500px;
    margin-bottom: var(--space-lg);
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: var(--space-sm);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 1.75rem;
    font-size: 0.875rem;
    font-weight: 500;
    letter-spacing: 0.03em;
    border-radius: 2px;
    transition: all var(--transition-base);
    cursor: pointer;
}

.btn-primary {
    background: var(--color-accent);
    color: var(--color-bg);
    border: 1px solid var(--color-accent);
}

.btn-primary:hover {
    background: transparent;
    color: var(--color-accent);
}

.btn-secondary {
    background: transparent;
    color: var(--color-text-primary);
    border: 1px solid var(--color-border);
}

.btn-secondary:hover {
    border-color: var(--color-text-primary);
}

/* Hero Visual - Animated Globe */
.hero-visual {
    display: flex;
    align-items: center;
    justify-content: center;
    animation: fadeIn 1s ease 0.3s forwards;
    opacity: 0;
}

.globe {
    position: relative;
    width: 400px;
    height: 400px;
}

.globe-ring {
    position: absolute;
    border: 1px solid var(--color-border);
    border-radius: 50%;
    animation: rotate 20s linear infinite;
}

.ring-1 {
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    transform: rotateX(70deg);
}

.ring-2 {
    width: 80%;
    height: 80%;
    top: 10%;
    left: 10%;
    transform: rotateX(70deg) rotateY(30deg);
    animation-duration: 25s;
    animation-direction: reverse;
}

.ring-3 {
    width: 60%;
    height: 60%;
    top: 20%;
    left: 20%;
    transform: rotateX(70deg) rotateY(-20deg);
    animation-duration: 30s;
}

.globe-core {
    position: absolute;
    width: 8px;
    height: 8px;
    background: var(--color-accent);
    border-radius: 50%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    box-shadow: 0 0 40px var(--color-accent), 0 0 80px var(--color-accent-dim);
}

.globe-dot {
    position: absolute;
    width: 4px;
    height: 4px;
    background: var(--color-accent);
    border-radius: 50%;
    opacity: 0.6;
}

.dot-1 { top: 30%; left: 25%; animation: pulse 2s ease infinite; }
.dot-2 { top: 45%; left: 70%; animation: pulse 2s ease infinite 0.5s; }
.dot-3 { top: 65%; left: 35%; animation: pulse 2s ease infinite 1s; }
.dot-4 { top: 55%; left: 55%; animation: pulse 2s ease infinite 1.5s; }

/* ============================================
   SECTIONS
   ============================================ */

section {
    padding: var(--space-2xl) var(--space-lg);
    max-width: 1400px;
    margin: 0 auto;
}

.section-header {
    display: flex;
    align-items: baseline;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.section-number {
    font-family: var(--font-display);
    font-size: 0.875rem;
    color: var(--color-accent);
    opacity: 0.7;
}

.section-title {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 400;
}

/* ============================================
   FEATURED SECTION
   ============================================ */

.featured {
    border-top: 1px solid var(--color-border);
}

.featured-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    padding: var(--space-xl);
    transition: border-color var(--transition-base);
}

.featured-card:hover {
    border-color: var(--color-border-hover);
}

.featured-meta {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
}

.featured-tag {
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-accent);
    background: var(--color-accent-dim);
    padding: 0.25rem 0.75rem;
}

.featured-year {
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
}

.featured-title {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 400;
    line-height: 1.3;
    margin-bottom: var(--space-md);
}

.featured-abstract {
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-md);
    max-width: 800px;
}

.featured-link {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-accent);
    transition: opacity var(--transition-fast);
}

.featured-link:hover {
    opacity: 0.8;
}

/* ============================================
   RESEARCH AREAS
   ============================================ */

.areas {
    border-top: 1px solid var(--color-border);
}

.areas-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
}

.area-card {
    background: var(--color-bg-elevated);
    border: 1px solid var(--color-border);
    padding: var(--space-lg);
    transition: all var(--transition-base);
}

.area-card:hover {
    border-color: var(--color-border-hover);
    transform: translateY(-4px);
}

.area-icon {
    font-size: 1.5rem;
    color: var(--color-accent);
    display: block;
    margin-bottom: var(--space-md);
}

.area-title {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 500;
    margin-bottom: var(--space-sm);
}

.area-desc {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ============================================
   RESEARCH PAGE
   ============================================ */

.page-header {
    padding: var(--space-2xl) var(--space-lg);
    max-width: 1400px;
    margin: 0 auto;
    border-bottom: 1px solid var(--color-border);
}

.page-title {
    font-family: var(--font-display);
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 400;
    margin-bottom: var(--space-sm);
}

.page-subtitle {
    color: var(--color-text-secondary);
    font-size: 1.125rem;
    max-width: 600px;
}

.research-section {
    padding: var(--space-xl) var(--space-lg);
    max-width: 1400px;
    margin: 0 auto;
}

.research-area {
    margin-bottom: var(--space-2xl);
}

.research-area-title {
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 400;
    margin-bottom: var(--space-sm);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.research-area-title::before {
    content: '';
    width: 24px;
    height: 1px;
    background: var(--color-accent);
}

.research-area-desc {
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-md);
    max-width: 800px;
}

.research-topics {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
}

.research-topic {
    font-size: 0.8125rem;
    color: var(--color-text-tertiary);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    padding: 0.375rem 0.875rem;
}

/* ============================================
   PUBLICATIONS PAGE
   ============================================ */

.publications-list {
    padding: var(--space-xl) var(--space-lg);
    max-width: 1400px;
    margin: 0 auto;
}

.publication-item {
    padding: var(--space-lg) 0;
    border-bottom: 1px solid var(--color-border);
}

.publication-item:first-child {
    padding-top: 0;
}

.publication-year {
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.1em;
    color: var(--color-accent);
    margin-bottom: var(--space-xs);
}

.publication-title {
    font-family: var(--font-display);
    font-size: 1.375rem;
    font-weight: 400;
    line-height: 1.4;
    margin-bottom: var(--space-sm);
}

.publication-authors {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-sm);
}

.publication-venue {
    font-size: 0.875rem;
    font-style: italic;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-md);
}

.publication-abstract {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-md);
    max-width: 900px;
}

.publication-links {
    display: flex;
    gap: var(--space-sm);
}

.publication-link {
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--color-accent);
    border: 1px solid var(--color-accent);
    padding: 0.5rem 1rem;
    transition: all var(--transition-fast);
}

.publication-link:hover {
    background: var(--color-accent);
    color: var(--color-bg);
}

/* ============================================
   ABOUT PAGE
   ============================================ */

.about-content {
    padding: var(--space-xl) var(--space-lg);
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--space-2xl);
}

.about-bio h3 {
    font-family: var(--font-display);
    font-size: 1.375rem;
    font-weight: 400;
    margin-bottom: var(--space-md);
    margin-top: var(--space-lg);
}

.about-bio h3:first-child {
    margin-top: 0;
}

.about-bio p {
    color: var(--color-text-secondary);
    line-height: 1.9;
    margin-bottom: var(--space-md);
}

.about-sidebar {
    border-left: 1px solid var(--color-border);
    padding-left: var(--space-xl);
}

.about-card {
    margin-bottom: var(--space-lg);
}

.about-card-label {
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-xs);
}

.about-card-value {
    font-family: var(--font-display);
    font-size: 1.125rem;
}

/* ============================================
   CONTACT PAGE
   ============================================ */

.contact-content {
    padding: var(--space-xl) var(--space-lg);
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-2xl);
}

.contact-info h3 {
    font-family: var(--font-display);
    font-size: 1.25rem;
    font-weight: 400;
    margin-bottom: var(--space-md);
}

.contact-info p {
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--space-lg);
}

.contact-email {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: 1.25rem;
    color: var(--color-accent);
    margin-bottom: var(--space-lg);
}

.contact-form {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    padding: var(--space-xl);
}

.form-group {
    margin-bottom: var(--space-md);
}

.form-label {
    display: block;
    font-size: 0.8125rem;
    font-weight: 500;
    letter-spacing: 0.05em;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-xs);
}

.form-input,
.form-textarea {
    width: 100%;
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    color: var(--color-text-primary);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    padding: 0.875rem 1rem;
    transition: border-color var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-accent);
}

.form-textarea {
    min-height: 150px;
    resize: vertical;
}

.form-submit {
    width: 100%;
    margin-top: var(--space-sm);
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
    border-top: 1px solid var(--color-border);
    padding: var(--space-xl) var(--space-lg);
    margin-top: var(--space-2xl);
}

.footer-container {
    max-width: 1400px;
    margin: 0 auto;
    text-align: center;
}

.footer-brand {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    margin-bottom: var(--space-sm);
}

.footer-tagline {
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-md);
}

.footer-contact a {
    color: var(--color-accent);
    font-size: 0.9375rem;
}

.footer-copy {
    font-size: 0.8125rem;
    color: var(--color-text-tertiary);
    margin-top: var(--space-lg);
}

/* ============================================
   ANIMATIONS
   ============================================ */

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

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes rotate {
    from { transform: rotateX(70deg) rotateZ(0deg); }
    to { transform: rotateX(70deg) rotateZ(360deg); }
}

@keyframes pulse {
    0%, 100% { opacity: 0.4; transform: scale(1); }
    50% { opacity: 1; transform: scale(1.5); }
}

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 1024px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        min-height: auto;
        padding-top: var(--space-xl);
    }
    
    .hero-subtitle {
        margin-left: auto;
        margin-right: auto;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .hero-visual {
        order: -1;
    }
    
    .globe {
        width: 280px;
        height: 280px;
    }
    
    .areas-grid {
        grid-template-columns: 1fr;
    }
    
    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
    }
    
    .about-sidebar {
        border-left: none;
        border-top: 1px solid var(--color-border);
        padding-left: 0;
        padding-top: var(--space-xl);
    }
}

@media (max-width: 768px) {
    :root {
        --space-lg: 2rem;
        --space-xl: 3rem;
        --space-2xl: 4rem;
    }
    
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        flex-direction: column;
        padding: var(--space-md);
        gap: var(--space-sm);
    }
    
    .nav-links.active {
        display: flex;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
}