/* ============================================
   PORTFOLIO - Oghenemaiga Elebe
   Site Reliability Engineer
   ============================================ */

/* ---- Reset & Base ---- */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

/* ---- CSS Custom Properties ---- */
:root {
    /* Colors - Dark Theme (default) */
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-tertiary: #1a1a26;
    --bg-card: #15151f;
    --text-primary: #f0f0f5;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --accent: #06b6d4;
    --accent-secondary: #3b82f6;
    --accent-success: #10b981;
    --accent-warning: #f59e0b;
    --border: rgba(255, 255, 255, 0.08);
    --border-hover: rgba(6, 182, 212, 0.4);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 24px rgba(6, 182, 212, 0.2);
    --gradient: linear-gradient(135deg, #06b6d4, #3b82f6);
    --gradient-subtle: linear-gradient(135deg, rgba(6, 182, 212, 0.1), rgba(59, 130, 246, 0.1));

    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
    --text-sm: clamp(0.875rem, 0.83rem + 0.2vw, 1rem);
    --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
    --text-lg: clamp(1.125rem, 1rem + 0.5vw, 1.5rem);
    --text-xl: clamp(1.5rem, 1.2rem + 1.2vw, 2.5rem);
    --text-2xl: clamp(2rem, 1.5rem + 2vw, 3.5rem);

    /* Spacing */
    --section-py: clamp(80px, 10vw, 140px);
    --container-max: 1200px;

    /* Transitions */
    --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---- Light Theme ---- */
[data-theme="light"] {
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f1f5f9;
    --bg-card: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    --accent: #0891b2;
    --accent-secondary: #2563eb;
    --border: rgba(0, 0, 0, 0.08);
    --border-hover: rgba(8, 145, 178, 0.4);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-glow: 0 0 24px rgba(8, 145, 178, 0.15);
    --gradient-subtle: linear-gradient(135deg, rgba(8, 145, 178, 0.06), rgba(37, 99, 235, 0.06));
}

/* ---- Base Styles ---- */
html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-sans);
    font-size: var(--text-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    transition: background-color 0.3s var(--ease), color 0.3s var(--ease);
}

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

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

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

ul {
    list-style: none;
}

.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: var(--section-py) 0;
}

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

/* ---- Skip Link ---- */
.skip-link {
    position: fixed;
    top: -100%;
    left: 1rem;
    z-index: 9999;
    background: var(--accent);
    color: #fff;
    padding: 0.75rem 1.5rem;
    border-radius: 0 0 8px 8px;
    font-weight: 600;
    transition: top 0.2s;
}
.skip-link:focus {
    top: 0;
    color: #fff;
}

/* ---- Navigation ---- */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: transparent;
    transition: background-color 0.3s var(--ease), backdrop-filter 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.nav.scrolled {
    background: rgba(10, 10, 15, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 1px 0 var(--border);
}

[data-theme="light"] .nav.scrolled {
    background: rgba(248, 250, 252, 0.85);
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}
.nav-logo:hover {
    color: var(--text-primary);
}

.nav-menu {
    display: flex;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    font-size: var(--text-sm);
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
    transition: color 0.2s var(--ease);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient);
    transition: width 0.3s var(--ease);
}

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

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

.nav-actions {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* Theme Toggle */
.theme-toggle {
    width: 40px;
    height: 40px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s var(--ease);
}

.theme-toggle:hover {
    border-color: var(--accent);
    color: var(--accent);
}

[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: block; }
[data-theme="light"] .icon-sun { display: block; }
[data-theme="light"] .icon-moon { display: none; }

/* Hamburger */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: 10px;
    cursor: pointer;
}

.hamburger span {
    display: block;
    width: 20px;
    height: 2px;
    background: var(--text-primary);
    transition: all 0.3s var(--ease);
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}
.hamburger.active span:nth-child(2) {
    opacity: 0;
}
.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ---- Hero Section ---- */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    padding: 100px 1.5rem 60px;
}

.hero-bg-mesh {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 30% 20%, rgba(6, 182, 212, 0.12) 0%, transparent 50%),
        radial-gradient(ellipse at 70% 80%, rgba(59, 130, 246, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

[data-theme="light"] .hero-bg-mesh {
    background:
        radial-gradient(ellipse at 30% 20%, rgba(8, 145, 178, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 70% 80%, rgba(37, 99, 235, 0.06) 0%, transparent 50%);
}

.hero-content {
    text-align: center;
    position: relative;
    z-index: 1;
    max-width: 800px;
}

/* Profile Photo */
.hero-photo {
    position: relative;
    width: 180px;
    height: 180px;
    margin: 0 auto 2rem;
}

.hero-photo img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 50%;
    position: relative;
    z-index: 1;
}

.photo-border {
    position: absolute;
    inset: -4px;
    border-radius: 50%;
    background: var(--gradient);
    animation: rotate 4s linear infinite;
}

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

/* To make the rotating gradient visible, we need a conic approach */
.photo-border {
    background: conic-gradient(from 0deg, #06b6d4, #3b82f6, #06b6d4);
}

.hero-name {
    font-size: var(--text-2xl);
    font-weight: 700;
    letter-spacing: -0.03em;
    margin-bottom: 0.5rem;
    line-height: 1.2;
}

.hero-title {
    font-size: var(--text-lg);
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    font-weight: 400;
}

.hero-tagline {
    font-size: var(--text-base);
    color: var(--text-muted);
    margin-bottom: 2.5rem;
    min-height: 1.6em;
    font-family: var(--font-mono);
    font-size: var(--text-sm);
}

.hero-tagline::after {
    content: '|';
    animation: blink 1s step-end infinite;
    color: var(--accent);
}

@keyframes blink {
    50% { opacity: 0; }
}

/* Hero Metrics */
.hero-metrics {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.metric {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.metric-value {
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--accent);
    font-family: var(--font-mono);
}

.metric-suffix {
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--accent);
    font-family: var(--font-mono);
}

.metric-label {
    font-size: var(--text-xs);
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-top: 0.25rem;
}

/* Hero CTAs */
.hero-ctas {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* ---- Buttons ---- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.75rem;
    border-radius: 10px;
    font-weight: 600;
    font-size: var(--text-sm);
    transition: all 0.3s var(--ease);
    cursor: pointer;
    border: none;
    text-decoration: none;
}

.btn-primary {
    background: var(--gradient);
    color: #fff;
    box-shadow: 0 4px 16px rgba(6, 182, 212, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(6, 182, 212, 0.4);
    color: #fff;
}

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

.btn-secondary:hover {
    border-color: var(--accent);
    color: var(--accent);
    transform: translateY(-2px);
}

/* ---- Section Titles ---- */
.section-title {
    font-size: var(--text-xl);
    font-weight: 700;
    text-align: center;
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: var(--text-base);
    margin-bottom: 3rem;
}

/* ---- About Section ---- */
.about {
    background: var(--bg-secondary);
}

.about-text {
    max-width: 800px;
    margin: 0 auto 3rem;
    text-align: center;
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: var(--text-base);
}

.highlights-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.highlight-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2rem;
    transition: all 0.3s var(--ease);
}

.highlight-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-glow);
    border-color: var(--border-hover);
}

.highlight-icon {
    width: 52px;
    height: 52px;
    border-radius: 12px;
    background: var(--gradient-subtle);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.25rem;
    color: var(--accent);
}

.highlight-card h3 {
    font-size: var(--text-lg);
    margin-bottom: 0.75rem;
    font-weight: 600;
}

.highlight-card p {
    color: var(--text-secondary);
    font-size: var(--text-sm);
    line-height: 1.7;
}

/* ---- Projects Section (Bento Grid) ---- */
.projects {
    background: var(--bg-primary);
}

.bento-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: repeat(3, minmax(280px, auto));
    gap: 1.5rem;
}

.project-card:nth-child(1) { grid-column: 1 / 3; grid-row: 1; }
.project-card:nth-child(2) { grid-column: 3 / 4; grid-row: 1; }
.project-card:nth-child(3) { grid-column: 1 / 2; grid-row: 2; }
.project-card:nth-child(4) { grid-column: 2 / 4; grid-row: 2; }
.project-card:nth-child(5) { grid-column: 1 / 4; grid-row: 3; }

.project-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
    transition: all 0.4s var(--ease);
}

.project-card::before {
    content: '';
    position: absolute;
    inset: 0;
    background: var(--gradient);
    opacity: 0;
    transition: opacity 0.4s var(--ease);
    pointer-events: none;
}

.project-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-md);
    border-color: var(--border-hover);
}

.project-card:hover::before {
    opacity: 0.05;
}

.project-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1.25rem;
    position: relative;
    z-index: 1;
}

.project-number {
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    color: var(--text-muted);
    font-weight: 500;
}

.project-impact {
    text-align: right;
}

.impact-value {
    display: block;
    font-size: var(--text-lg);
    font-weight: 700;
    color: var(--accent-success);
    font-family: var(--font-mono);
    line-height: 1.2;
}

.impact-label {
    font-size: var(--text-xs);
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.project-title {
    font-size: var(--text-lg);
    font-weight: 600;
    margin-bottom: 0.75rem;
    position: relative;
    z-index: 1;
}

.project-desc {
    color: var(--text-secondary);
    font-size: var(--text-sm);
    line-height: 1.7;
    margin-bottom: 1.5rem;
    flex: 1;
    position: relative;
    z-index: 1;
}

.tech-stack {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    position: relative;
    z-index: 1;
}

.tech-tag {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    padding: 0.3rem 0.65rem;
    border-radius: 6px;
    background: rgba(6, 182, 212, 0.08);
    color: var(--accent);
    border: 1px solid rgba(6, 182, 212, 0.2);
    transition: all 0.2s var(--ease);
}

.project-card:hover .tech-tag {
    background: rgba(6, 182, 212, 0.12);
    border-color: rgba(6, 182, 212, 0.35);
}

/* ---- Skills Section ---- */
.skills {
    background: var(--bg-primary);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1.5rem;
}

.skill-category {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.75rem;
    transition: all 0.3s var(--ease);
}

.skill-category:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
    border-color: var(--border-hover);
}

.skill-icon {
    width: 44px;
    height: 44px;
    border-radius: 10px;
    background: var(--gradient-subtle);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
    color: var(--accent);
}

.skill-category h3 {
    font-size: var(--text-sm);
    font-weight: 600;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.skill-list li {
    color: var(--text-secondary);
    font-size: var(--text-sm);
    padding: 0.4rem 0;
    border-bottom: 1px solid var(--border);
    transition: color 0.2s var(--ease);
}

.skill-list li:last-child {
    border-bottom: none;
}

.skill-list li:hover {
    color: var(--text-primary);
}

/* ---- Published Papers Section ---- */
.papers {
    background: var(--bg-secondary);
}

.papers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.paper-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    transition: all 0.3s var(--ease);
    position: relative;
}

.paper-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-glow);
    border-color: var(--border-hover);
}

.paper-icon {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    background: var(--gradient-subtle);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1rem;
    color: var(--accent);
}

.paper-year {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    font-family: var(--font-mono);
    font-size: var(--text-xs);
    font-weight: 600;
    color: var(--accent);
    background: rgba(6, 182, 212, 0.1);
    padding: 0.25rem 0.65rem;
    border-radius: 6px;
    border: 1px solid rgba(6, 182, 212, 0.2);
}

.paper-title {
    font-size: var(--text-sm);
    font-weight: 600;
    line-height: 1.5;
    margin-bottom: 1rem;
    color: var(--text-primary);
    display: -webkit-box;
    -webkit-line-clamp: 3;
    line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.paper-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.25rem;
    flex: 1;
}

.paper-tag {
    font-family: var(--font-mono);
    font-size: 0.65rem;
    padding: 0.25rem 0.6rem;
    border-radius: 6px;
    background: rgba(59, 130, 246, 0.08);
    color: var(--accent-secondary);
    border: 1px solid rgba(59, 130, 246, 0.2);
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.paper-link {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--accent);
    transition: gap 0.3s var(--ease);
    margin-top: auto;
}

.paper-link:hover {
    gap: 0.6rem;
    color: var(--accent);
}

.paper-hidden {
    display: none;
}

.papers-footer {
    display: flex;
    justify-content: center;
    margin-top: 1rem;
}

.papers-footer .btn svg {
    transition: transform 0.3s var(--ease);
}

.papers-footer .btn.expanded svg {
    transform: rotate(180deg);
}

/* ---- Media Mentions Section ---- */
.media {
    background: var(--bg-secondary);
}

.media-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.media-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2.5rem;
    transition: all 0.3s var(--ease);
    position: relative;
    overflow: hidden;
}

.media-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--gradient);
    opacity: 0;
    transition: opacity 0.3s var(--ease);
}

.media-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
    border-color: var(--border-hover);
}

.media-card:hover::before {
    opacity: 1;
}

.media-header {
    margin-bottom: 1.5rem;
}

.media-publisher {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.publisher-icon {
    width: 48px;
    height: 48px;
    min-width: 48px;
    border-radius: 10px;
    background: var(--gradient-subtle);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent);
}

.publisher-info h4 {
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.2rem;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.media-date {
    font-size: var(--text-xs);
    color: var(--text-muted);
    font-family: var(--font-mono);
}

.media-title {
    font-size: var(--text-lg);
    font-weight: 600;
    line-height: 1.4;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.media-quote {
    position: relative;
    padding: 1.5rem;
    margin: 1.5rem 0;
    background: var(--gradient-subtle);
    border-radius: 12px;
    border-left: 3px solid var(--accent);
}

.quote-icon {
    position: absolute;
    top: 1rem;
    right: 1rem;
    opacity: 0.15;
    color: var(--accent);
}

.media-quote p {
    font-size: var(--text-base);
    line-height: 1.7;
    color: var(--text-secondary);
    font-style: italic;
    position: relative;
    z-index: 1;
}

.media-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--accent);
    margin-top: 1rem;
    transition: gap 0.3s var(--ease);
}

.media-link:hover {
    gap: 0.75rem;
    color: var(--accent);
}

/* ---- Contact Section ---- */
.contact {
    background: var(--bg-primary);
}

.contact-container {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 4rem;
    align-items: flex-start;
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    font-size: var(--text-sm);
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.form-input {
    width: 100%;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 0.85rem 1rem;
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: var(--text-sm);
    transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.form-input::placeholder {
    color: var(--text-muted);
}

.form-input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.1);
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

.btn-submit {
    width: 100%;
    justify-content: center;
    padding: 0.9rem;
    margin-top: 0.5rem;
}

/* Contact Info */
.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    padding-top: 0.5rem;
}

.info-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
}

.info-icon {
    width: 44px;
    height: 44px;
    min-width: 44px;
    border-radius: 10px;
    background: var(--gradient-subtle);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--accent);
}

.info-item h4 {
    font-size: var(--text-sm);
    font-weight: 600;
    margin-bottom: 0.2rem;
}

.info-item p,
.info-item a {
    color: var(--text-secondary);
    font-size: var(--text-sm);
}

.social-links {
    display: flex;
    gap: 0.75rem;
    margin-top: 1rem;
}

.social-link {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    transition: all 0.3s var(--ease);
}

.social-link:hover {
    background: var(--gradient);
    border-color: transparent;
    color: #fff;
    transform: translateY(-3px);
}

/* ---- Footer ---- */
.footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border);
    padding: 2rem 0;
    text-align: center;
}

.footer p {
    color: var(--text-muted);
    font-size: var(--text-sm);
}

/* ---- Animations ---- */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
}

.animate-on-scroll.in-view {
    opacity: 1;
    transform: translateY(0);
}

/* Stagger children */
.highlights-grid .animate-on-scroll:nth-child(2) { transition-delay: 0.1s; }
.highlights-grid .animate-on-scroll:nth-child(3) { transition-delay: 0.2s; }

.bento-grid .animate-on-scroll:nth-child(2) { transition-delay: 0.1s; }
.bento-grid .animate-on-scroll:nth-child(3) { transition-delay: 0.2s; }
.bento-grid .animate-on-scroll:nth-child(4) { transition-delay: 0.3s; }
.bento-grid .animate-on-scroll:nth-child(5) { transition-delay: 0.4s; }

.skills-grid .animate-on-scroll:nth-child(2) { transition-delay: 0.05s; }
.skills-grid .animate-on-scroll:nth-child(3) { transition-delay: 0.1s; }
.skills-grid .animate-on-scroll:nth-child(4) { transition-delay: 0.15s; }
.skills-grid .animate-on-scroll:nth-child(5) { transition-delay: 0.2s; }

/* ---- Responsive ---- */

/* Tablet */
@media (max-width: 1024px) {
    .bento-grid {
        grid-template-columns: repeat(2, 1fr);
        grid-template-rows: auto;
    }
    .project-card:nth-child(1),
    .project-card:nth-child(2),
    .project-card:nth-child(3),
    .project-card:nth-child(4),
    .project-card:nth-child(5) {
        grid-column: auto;
        grid-row: auto;
    }

    .contact-container {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
}

/* Mobile */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 320px;
        height: 100vh;
        background: var(--bg-secondary);
        flex-direction: column;
        padding: 5rem 2rem 2rem;
        gap: 0.5rem;
        transition: right 0.3s var(--ease);
        box-shadow: -4px 0 20px rgba(0, 0, 0, 0.3);
        z-index: 999;
    }

    .nav-menu.active {
        right: 0;
    }

    .nav-menu .nav-link {
        font-size: var(--text-base);
        padding: 0.75rem 0;
        border-bottom: 1px solid var(--border);
        display: block;
    }

    .hamburger {
        display: flex;
    }

    .bento-grid {
        grid-template-columns: 1fr;
        grid-template-rows: auto;
        gap: 1rem;
    }

    .project-card {
        padding: 1.5rem;
    }

    .hero-metrics {
        gap: 2rem;
    }

    .hero-photo {
        width: 140px;
        height: 140px;
    }

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

    .skills-grid {
        grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
    }

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

    .media-card {
        padding: 2rem 1.5rem;
    }

    .media-quote {
        padding: 1.25rem;
    }

    .quote-icon {
        width: 24px;
        height: 24px;
    }
}

/* Mobile overlay when menu is open */
.nav-menu.active::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.5);
    z-index: -1;
}

/* ---- Reduced Motion ---- */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }

    html {
        scroll-behavior: auto;
    }

    .animate-on-scroll {
        opacity: 1;
        transform: none;
    }
}