/* ==========================================
   CSS Variables & Reset
   ========================================== */
:root {
    /* Color Palette */
    --primary-color: #2563eb;
    --secondary-color: #7c3aed;
    --accent-color: #f59e0b;
    --dark-color: #0f172a;
    --dark-light: #1e293b;
    --text-color: #334155;
    --text-light: #64748b;
    --white-color: #ffffff;
    --bg-color: #f8fafc;
    --border-color: #e2e8f0;
    
    /* Typography */
    --font-primary: 'Poppins', 'Noto Sans KR', sans-serif;
    --font-size-base: 16px;
    
    /* Spacing */
    --section-padding: 100px;
    --container-max-width: 1200px;
    
    /* Transitions */
    --transition-speed: 0.3s;
    
    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
    --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.15);
}

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

html {
    scroll-behavior: smooth;
    font-size: var(--font-size-base);
}

body {
    font-family: var(--font-primary);
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.6;
    overflow-x: hidden;
}

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

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

ul {
    list-style: none;
}

button {
    border: none;
    background: none;
    cursor: pointer;
    font-family: inherit;
}

/* ==========================================
   Loader
   ========================================== */
.loader-wrapper {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--dark-color);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.5s, visibility 0.5s;
}

.loader-wrapper.fade-out {
    opacity: 0;
    visibility: hidden;
}

.loader {
    width: 60px;
    height: 60px;
    border: 4px solid rgba(255, 255, 255, 0.1);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* ==========================================
   Container & Utilities
   ========================================== */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 20px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 32px;
    border-radius: 50px;
    font-weight: 500;
    font-size: 15px;
    transition: all var(--transition-speed);
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 0;
    height: 100%;
    background: rgba(255, 255, 255, 0.1);
    transition: width var(--transition-speed);
    z-index: -1;
}

.btn:hover::before {
    width: 100%;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white-color);
    box-shadow: 0 4px 16px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.4);
}

.btn-secondary {
    background: transparent;
    color: var(--white-color);
    border: 2px solid var(--white-color);
}

.btn-secondary:hover {
    background: var(--white-color);
    color: var(--primary-color);
}

/* ==========================================
   Navigation
   ========================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    padding: 20px 0;
    z-index: 1000;
    transition: padding var(--transition-speed);
}

.navbar.scrolled {
    padding: 15px 0;
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 16px;
    font-weight: 600;
    color: var(--white-color);
    display: flex;
    align-items: center;
    line-height: 1.3;
}

.logo-multi-line {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.logo-text {
    color: var(--white-color);
    font-size: 14px;
}

.logo-accent {
    color: var(--primary-color);
    font-size: 16px;
}

.nav-menu {
    display: flex;
    gap: 40px;
}

.nav-link {
    color: var(--white-color);
    font-weight: 500;
    position: relative;
    transition: color var(--transition-speed);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width var(--transition-speed);
}

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

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

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

.nav-toggle span {
    width: 28px;
    height: 3px;
    background: var(--white-color);
    border-radius: 2px;
    transition: all var(--transition-speed);
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* ==========================================
   Hero Section
   ========================================== */
.hero-section {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    padding-top: 80px;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--dark-color) 0%, var(--dark-light) 100%);
    z-index: -1;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 50%, rgba(37, 99, 235, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(124, 58, 237, 0.15) 0%, transparent 50%);
}

.hero-shapes {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.shape {
    position: absolute;
    border-radius: 50%;
    opacity: 0.1;
}

.shape-1 {
    width: 500px;
    height: 500px;
    background: var(--primary-color);
    top: -250px;
    right: -100px;
    animation: float 20s infinite ease-in-out;
}

.shape-2 {
    width: 350px;
    height: 350px;
    background: var(--secondary-color);
    bottom: -150px;
    left: -100px;
    animation: float 25s infinite ease-in-out reverse;
}

.shape-3 {
    width: 200px;
    height: 200px;
    background: var(--accent-color);
    top: 50%;
    left: 50%;
    animation: float 15s infinite ease-in-out;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(30px, -30px) scale(1.1); }
    66% { transform: translate(-20px, 20px) scale(0.9); }
}

.hero-content {
    position: relative;
    text-align: center;
    color: var(--white-color);
    padding: 0 20px;
    max-width: 900px;
    margin: 0 auto;
}

.hero-title {
    font-size: 64px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 20px;
    opacity: 0;
    animation: fadeInUp 1s forwards 0.3s;
}

.title-line {
    display: block;
}

.hero-subtitle {
    font-size: 20px;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 40px;
    opacity: 0;
    animation: fadeInUp 1s forwards 0.6s;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    opacity: 0;
    animation: fadeInUp 1s forwards 0.9s;
}

.hero-scroll {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    opacity: 0;
    animation: fadeIn 1s forwards 1.2s;
}

.scroll-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    color: rgba(255, 255, 255, 0.6);
    font-size: 14px;
    transition: color var(--transition-speed);
}

.scroll-indicator:hover {
    color: var(--primary-color);
}

.scroll-indicator i {
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(10px); }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* ==========================================
   Section Styles
   ========================================== */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white-color);
    padding: 8px 20px;
    border-radius: 50px;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 15px;
}

.section-title {
    font-size: 48px;
    font-weight: 700;
    color: var(--dark-color);
    margin-bottom: 15px;
}

.section-description {
    font-size: 18px;
    color: var(--text-light);
    max-width: 600px;
    margin: 0 auto;
}

/* ==========================================
   About Section
   ========================================== */
.about-section {
    padding: var(--section-padding) 0;
    background: var(--white-color);
}

.about-content {
    margin-top: 60px;
}

.about-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

.about-card {
    background: var(--bg-color);
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    transition: all var(--transition-speed);
    border: 2px solid transparent;
}

.about-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.card-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    color: var(--white-color);
}

.about-card h3 {
    font-size: 22px;
    color: var(--dark-color);
    margin-bottom: 10px;
}

.about-card p {
    color: var(--text-light);
    line-height: 1.8;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    padding: 60px 40px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 20px;
    text-align: center;
}

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

.stat-number {
    font-size: 56px;
    font-weight: 700;
    color: var(--white-color);
}

.stat-label {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.9);
}

/* ==========================================
   Portfolio Section
   ========================================== */
.portfolio-section {
    padding: var(--section-padding) 0;
    background: var(--bg-color);
}

.portfolio-filter {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 50px;
}

.filter-btn {
    padding: 12px 28px;
    border-radius: 50px;
    background: var(--white-color);
    color: var(--text-color);
    font-weight: 500;
    transition: all var(--transition-speed);
    border: 2px solid transparent;
}

.filter-btn:hover,
.filter-btn.active {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 40px;
}

.portfolio-item {
    background: var(--white-color);
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-speed);
    opacity: 1;
    transform: scale(1);
}

.portfolio-item.hide {
    opacity: 0;
    transform: scale(0.8);
    position: absolute;
    pointer-events: none;
}

.portfolio-item:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.portfolio-image {
    position: relative;
    overflow: hidden;
    height: 300px;
}

.portfolio-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s;
}

.portfolio-item:hover .portfolio-image img {
    transform: scale(1.1);
}

.portfolio-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.95), rgba(124, 58, 237, 0.95));
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity var(--transition-speed);
}

.portfolio-item:hover .portfolio-overlay {
    opacity: 1;
}

.overlay-content {
    text-align: center;
    color: var(--white-color);
    padding: 20px;
}

.overlay-content h3 {
    font-size: 24px;
    margin-bottom: 10px;
}

.overlay-content p {
    margin-bottom: 20px;
    opacity: 0.9;
}

.view-btn {
    padding: 12px 28px;
    background: var(--white-color);
    color: var(--primary-color);
    border-radius: 50px;
    font-weight: 500;
    transition: all var(--transition-speed);
}

.view-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.portfolio-info {
    padding: 30px;
}

.portfolio-tags {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
}

.tag {
    padding: 6px 14px;
    background: var(--bg-color);
    color: var(--primary-color);
    border-radius: 50px;
    font-size: 12px;
    font-weight: 500;
}

.portfolio-title {
    font-size: 22px;
    color: var(--dark-color);
    margin-bottom: 10px;
}

.portfolio-description {
    color: var(--text-light);
    line-height: 1.8;
}

/* ==========================================
   Contact Section
   ========================================== */
.contact-section {
    padding: var(--section-padding) 0;
    background: var(--white-color);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 60px;
    margin-top: 60px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.contact-card {
    padding: 30px;
    background: var(--bg-color);
    border-radius: 15px;
    text-align: center;
    transition: all var(--transition-speed);
}

.contact-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.contact-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 15px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--white-color);
}

.contact-card h3 {
    font-size: 18px;
    color: var(--dark-color);
    margin-bottom: 8px;
}

.contact-card p {
    color: var(--text-light);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
}

.form-group {
    position: relative;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 16px 20px;
    background: var(--bg-color);
    border: 2px solid transparent;
    border-radius: 10px;
    font-family: inherit;
    font-size: 15px;
    color: var(--text-color);
    transition: all var(--transition-speed);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    background: var(--white-color);
}

.form-group label {
    position: absolute;
    top: 16px;
    left: 20px;
    color: var(--text-light);
    pointer-events: none;
    transition: all var(--transition-speed);
}

.form-group input:focus + label,
.form-group input:valid + label,
.form-group textarea:focus + label,
.form-group textarea:valid + label {
    top: -10px;
    left: 15px;
    font-size: 12px;
    color: var(--primary-color);
    background: var(--white-color);
    padding: 0 8px;
}

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

/* ==========================================
   Footer
   ========================================== */
.footer {
    background: var(--dark-color);
    color: var(--white-color);
    padding: 60px 0 30px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
    flex-wrap: wrap;
    gap: 30px;
}

.footer-brand h3 {
    font-size: 24px;
    margin-bottom: 10px;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.7);
    max-width: 400px;
}

.footer-social {
    display: flex;
    gap: 15px;
}

.social-link {
    width: 45px;
    height: 45px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    transition: all var(--transition-speed);
}

.social-link:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
}

/* ==========================================
   Modal
   ========================================== */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 2000;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal.active {
    display: flex;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
}

.modal-content {
    position: relative;
    background: var(--white-color);
    border-radius: 20px;
    max-width: 900px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-xl);
    animation: modalSlideIn 0.3s;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-close {
    position: absolute;
    top: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
    background: var(--dark-color);
    color: var(--white-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    transition: all var(--transition-speed);
    z-index: 10;
}

.modal-close:hover {
    background: var(--primary-color);
    transform: rotate(90deg);
}

.modal-body {
    padding: 60px 40px;
}

.modal-header h2 {
    font-size: 36px;
    color: var(--dark-color);
    margin-bottom: 20px;
}

.modal-tags {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
}

.modal-image {
    width: 100%;
    height: 400px;
    border-radius: 15px;
    overflow: hidden;
    margin-bottom: 30px;
}

.modal-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.modal-description {
    color: var(--text-color);
    line-height: 1.8;
    margin-bottom: 30px;
}

.modal-details {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    padding: 30px;
    background: var(--bg-color);
    border-radius: 15px;
}

.detail-item h4 {
    font-size: 14px;
    color: var(--text-light);
    margin-bottom: 8px;
}

.detail-item p {
    font-size: 16px;
    color: var(--dark-color);
    font-weight: 500;
}

/* ==========================================
   Responsive Design
   ========================================== */
@media (max-width: 1024px) {
    :root {
        --section-padding: 80px;
    }
    
    .hero-title {
        font-size: 52px;
    }
    
    .section-title {
        font-size: 40px;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    :root {
        --section-padding: 60px;
    }
    
    .nav-menu {
        position: fixed;
        top: 80px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 80px);
        background: rgba(15, 23, 42, 0.98);
        backdrop-filter: blur(10px);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 30px;
        transition: left var(--transition-speed);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: 40px;
    }
    
    .hero-subtitle {
        font-size: 18px;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .section-title {
        font-size: 32px;
    }
    
    .about-stats {
        padding: 40px 20px;
    }
    
    .stat-number {
        font-size: 42px;
    }
    
    .portfolio-grid {
        grid-template-columns: 1fr;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .modal-body {
        padding: 40px 20px;
    }
    
    .modal-header h2 {
        font-size: 28px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 32px;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .btn {
        padding: 12px 24px;
        font-size: 14px;
    }
    
    .about-cards {
        grid-template-columns: 1fr;
    }
    
    .portfolio-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

/* ==========================================
   Academic Portfolio Specific Styles
   ========================================== */

/* Hero Tagline */
.hero-tagline {
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: var(--accent-color);
    margin-bottom: 20px;
    font-weight: 500;
    opacity: 0;
    animation: fadeInUp 1s forwards 0.2s;
}

.hero-subtitle-block {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 40px;
}

/* About Bio */
.about-bio {
    background: var(--bg-color);
    padding: 40px;
    border-radius: 15px;
    margin-bottom: 40px;
    border-left: 4px solid var(--primary-color);
}

.about-bio p {
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: 20px;
}

.about-bio p:last-child {
    margin-bottom: 0;
}

/* Featured Project */
.featured-project-section {
    padding: 80px 0;
    background: var(--bg-color);
}

.featured-project-card {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    background: var(--white-color);
    padding: 60px;
    border-radius: 20px;
    box-shadow: var(--shadow-md);
}

.featured-tag {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white-color);
    padding: 6px 16px;
    border-radius: 50px;
    font-size: 13px;
    font-weight: 500;
    margin-bottom: 20px;
}

.featured-content h3 {
    font-size: 32px;
    color: var(--dark-color);
    margin-bottom: 15px;
}

.featured-content p {
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: 30px;
}

.featured-image {
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.featured-image img {
    width: 100%;
    height: auto;
    display: block;
}

/* Research Section */
.research-section {
    padding: var(--section-padding) 0;
    background: var(--white-color);
}

.research-clusters {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.research-cluster {
    background: var(--bg-color);
    padding: 40px;
    border-radius: 15px;
    border-left: 4px solid var(--primary-color);
    transition: all var(--transition-speed);
}

.research-cluster:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-md);
}

.cluster-number {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white-color);
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 20px;
}

.research-cluster h3 {
    font-size: 26px;
    color: var(--dark-color);
    margin-bottom: 15px;
}

.research-cluster > p {
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: 20px;
}

.research-topics {
    list-style: none;
    padding: 0;
}

.research-topics li {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 16px;
    color: var(--text-color);
    margin-bottom: 12px;
}

.research-topics i {
    color: var(--primary-color);
    font-size: 18px;
}

/* Teaching Section */
.teaching-section {
    padding: var(--section-padding) 0;
    background: var(--bg-color);
}

.teaching-content {
    display: flex;
    flex-direction: column;
    gap: 50px;
}

.teaching-philosophy {
    background: var(--white-color);
    padding: 40px;
    border-radius: 15px;
    box-shadow: var(--shadow-sm);
}

.teaching-philosophy h3 {
    font-size: 24px;
    color: var(--dark-color);
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.teaching-philosophy h3 i {
    color: var(--primary-color);
}

.teaching-philosophy p {
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-color);
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.course-card {
    background: var(--white-color);
    padding: 30px;
    border-radius: 15px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-speed);
    border-top: 4px solid var(--primary-color);
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.course-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--white-color);
    margin-bottom: 20px;
}

.course-card h4 {
    font-size: 18px;
    color: var(--dark-color);
    margin-bottom: 12px;
    font-weight: 600;
}

.course-card p {
    font-size: 15px;
    line-height: 1.7;
    color: var(--text-color);
}

.student-deliverables {
    background: var(--white-color);
    padding: 40px;
    border-radius: 15px;
    box-shadow: var(--shadow-sm);
}

.student-deliverables h3 {
    font-size: 24px;
    color: var(--dark-color);
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.student-deliverables h3 i {
    color: var(--primary-color);
}

.student-deliverables > p {
    font-size: 17px;
    color: var(--text-color);
    margin-bottom: 20px;
}

.student-deliverables ul {
    list-style: none;
    padding: 0;
}

.student-deliverables li {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: 15px;
    padding-left: 25px;
    position: relative;
}

.student-deliverables li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: 700;
}

.student-deliverables strong {
    color: var(--dark-color);
    font-weight: 600;
}

/* Publications Section */
.publications-section {
    padding: var(--section-padding) 0;
    background: var(--white-color);
}

.publications-content {
    max-width: 800px;
    margin: 0 auto;
}

.publications-placeholder {
    background: var(--bg-color);
    padding: 60px 40px;
    border-radius: 15px;
    text-align: center;
}

.publications-placeholder i {
    font-size: 48px;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.publications-placeholder p {
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: 15px;
}

.publications-placeholder .note {
    font-size: 15px;
    color: var(--text-light);
    font-style: italic;
}

/* CV Section */
.cv-section {
    padding: var(--section-padding) 0;
    background: var(--bg-color);
}

.cv-content {
    max-width: 600px;
    margin: 0 auto;
}

.cv-download {
    background: var(--white-color);
    padding: 60px 40px;
    border-radius: 15px;
    text-align: center;
    box-shadow: var(--shadow-sm);
}

.cv-download i {
    font-size: 48px;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.cv-download h3 {
    font-size: 24px;
    color: var(--dark-color);
    margin-bottom: 15px;
}

.cv-download p {
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-color);
    margin-bottom: 25px;
}

.cv-download .note {
    font-size: 14px;
    color: var(--text-light);
    font-style: italic;
    margin-top: 15px;
}

.cv-download .btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* Artifacts Page */
.artifacts-header {
    padding: 140px 0 60px;
    background: linear-gradient(135deg, var(--dark-color) 0%, var(--dark-light) 100%);
    color: var(--white-color);
    text-align: center;
}

.page-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 15px;
}

.page-description {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.85);
}

.artifacts-section {
    padding: 80px 0;
    background: var(--white-color);
}

.artifacts-category {
    margin-bottom: 60px;
}

.category-title {
    font-size: 28px;
    color: var(--dark-color);
    margin-bottom: 30px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.category-title i {
    color: var(--primary-color);
}

.artifacts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
}

.artifact-card {
    background: var(--bg-color);
    padding: 30px;
    border-radius: 15px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    transition: all var(--transition-speed);
    border: 2px solid transparent;
}

.artifact-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.artifact-icon {
    width: 70px;
    height: 70px;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    color: var(--white-color);
}

.pdf-icon {
    background: linear-gradient(135deg, #ef4444, #dc2626);
}

.video-icon {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
}

.artifact-info {
    flex: 1;
}

.artifact-title {
    font-size: 16px;
    color: var(--dark-color);
    margin-bottom: 10px;
    font-weight: 600;
    word-break: break-word;
}

.artifact-description {
    font-size: 15px;
    line-height: 1.6;
    color: var(--text-color);
    margin-bottom: 15px;
}

.artifact-meta {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.meta-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: var(--white-color);
    border-radius: 50px;
    font-size: 12px;
    color: var(--text-light);
}

.meta-tag i {
    font-size: 11px;
}

.artifact-actions {
    display: flex;
    gap: 10px;
}

.btn-sm {
    padding: 10px 20px;
    font-size: 14px;
}

.artifacts-note {
    background: #eff6ff;
    border-left: 4px solid var(--primary-color);
    padding: 30px;
    border-radius: 10px;
    display: flex;
    gap: 15px;
    align-items: flex-start;
    margin-top: 40px;
}

.artifacts-note i {
    font-size: 24px;
    color: var(--primary-color);
    flex-shrink: 0;
    margin-top: 3px;
}

.artifacts-note p {
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-color);
    margin: 0;
}

.artifacts-note a {
    color: var(--primary-color);
    text-decoration: underline;
}

.artifacts-note a:hover {
    color: var(--secondary-color);
}

/* Responsive Academic Styles */
@media (max-width: 1024px) {
    .featured-project-card {
        grid-template-columns: 1fr;
        gap: 40px;
        padding: 40px;
    }
}

@media (max-width: 768px) {
    .hero-tagline {
        font-size: 12px;
    }

    .research-cluster:hover {
        transform: translateX(5px);
    }

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

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

    .page-title {
        font-size: 36px;
    }

    .logo-multi-line .logo-text {
        font-size: 12px;
    }

    .logo-multi-line .logo-accent {
        font-size: 14px;
    }
}