/* CSS Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-blue: #1565C0;
    --secondary-blue: #42A5F5;
    --accent-yellow: #FDD700;
    --dark-blue: #0D47A1;
    --light-blue: #E3F2FD;
    --text-dark: #212121;
    --text-gray: #616161;
    --text-light: #757575;
    --background-light: #FAFAFA;
    --background-white: #FFFFFF;
    --shadow-light: rgba(0, 0, 0, 0.1);
    --shadow-medium: rgba(0, 0, 0, 0.15);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px var(--shadow-light);
    z-index: 1000;
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo h2 {
    color: var(--primary-blue);
    font-weight: 700;
    font-size: 1.5rem;
    margin-bottom: 2px;
}

.nav-logo span {
    color: var(--text-gray);
    font-size: 0.8rem;
    font-weight: 400;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

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

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

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

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--primary-blue);
    margin: 3px 0;
    transition: var(--transition);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    background: linear-gradient(135deg, var(--light-blue) 0%, var(--background-white) 100%);
    display: flex;
    align-items: center;
    padding-top: 70px;
    position: relative;
    overflow: hidden;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--dark-blue);
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-gray);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    cursor: pointer;
    display: inline-block;
}

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

.btn-primary:hover {
    background: var(--dark-blue);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(21, 101, 192, 0.3);
}

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

.btn-secondary:hover {
    background: var(--primary-blue);
    color: white;
    transform: translateY(-2px);
}

.btn-small {
    padding: 8px 16px;
    font-size: 0.9rem;
    background: var(--primary-blue);
    color: white;
}

.btn-small:hover {
    background: var(--dark-blue);
    transform: translateY(-2px);
}

/* Data Visualization */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.data-visualization {
    position: relative;
    width: 300px;
    height: 300px;
}

.chart-element {
    position: absolute;
    background: var(--primary-blue);
    border-radius: 8px;
    animation: float 6s ease-in-out infinite;
}

.chart-element:nth-child(1) {
    width: 60px;
    height: 120px;
    top: 50px;
    left: 50px;
    animation-delay: 0s;
}

.chart-element:nth-child(2) {
    width: 60px;
    height: 180px;
    top: 10px;
    left: 120px;
    background: var(--secondary-blue);
    animation-delay: 2s;
}

.chart-element:nth-child(3) {
    width: 60px;
    height: 100px;
    top: 70px;
    left: 190px;
    background: var(--accent-yellow);
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

/* Section Styles */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--dark-blue);
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--accent-yellow);
    border-radius: 2px;
}

/* About Section */
.about {
    padding: 80px 0;
    background: var(--background-white);
}

.about-text p {
    font-size: 1.1rem;
    color: var(--text-gray);
    margin-bottom: 2rem;
    line-height: 1.8;
}

.research-highlights {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
    margin-top: 3rem;
}

.highlight-item {
    text-align: center;
    padding: 2rem;
    background: var(--light-blue);
    border-radius: 12px;
    transition: var(--transition);
}

.highlight-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px var(--shadow-medium);
}

.highlight-item .material-icons {
    font-size: 3rem;
    color: var(--primary-blue);
    margin-bottom: 1rem;
}

.highlight-item h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin-bottom: 0.5rem;
}

/* Leadership Section */
.leadership {
    padding: 80px 0;
    background: var(--background-light);
}

.directors-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
}

.directors-grid.single-director {
    grid-template-columns: 1fr;
    max-width: 800px;
    margin: 0 auto;
}

.director-card {
    background: var(--background-white);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: 0 10px 40px var(--shadow-light);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.director-photo {
    margin-bottom: 1.5rem;
}

.profile-img {
    width: 150px;
    height: 150px;
    border-radius: 50%;
    object-fit: cover;
    box-shadow: 0 8px 25px var(--shadow-medium);
}

.director-info {
    text-align: center;
    width: 100%;
}

.director-info h3 {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--dark-blue);
    margin-bottom: 0.5rem;
}

.director-title {
    font-size: 1rem;
    color: var(--primary-blue);
    font-weight: 500;
    margin-bottom: 1.5rem;
}

.director-info h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin: 1.5rem 0 0.8rem 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.education p, .contact-info p {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-gray);
}

.research-tags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.5rem;
}

.tag {
    background: var(--light-blue);
    color: var(--primary-blue);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition);
}

.tag:hover {
    background: var(--primary-blue);
    color: white;
}

/* Research Section */
.research {
    padding: 80px 0;
    background: var(--background-white);
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.research-card {
    background: var(--background-white);
    padding: 2.5rem;
    border-radius: 16px;
    box-shadow: 0 8px 30px var(--shadow-light);
    transition: var(--transition);
    border: 1px solid rgba(21, 101, 192, 0.1);
}

.research-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 40px var(--shadow-medium);
    border-color: var(--primary-blue);
}

.research-icon {
    background: var(--light-blue);
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.research-icon .material-icons {
    font-size: 2rem;
    color: var(--primary-blue);
}

.research-card h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin-bottom: 1rem;
}

.research-card p {
    color: var(--text-gray);
    line-height: 1.7;
}

/* Research Outputs Section */
.research-outputs {
    padding: 80px 0;
    background: var(--background-light);
}

.outputs-category {
    margin-bottom: 4rem;
}

.outputs-category h3 {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin-bottom: 2rem;
    padding-left: 1rem;
    border-left: 4px solid var(--accent-yellow);
}

/* Interactive Tools */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.tool-card {
    background: var(--background-white);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: 0 8px 25px var(--shadow-light);
    transition: var(--transition);
    text-align: center;
}

.tool-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 35px var(--shadow-medium);
}

.tool-icon {
    background: var(--light-blue);
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.tool-icon .material-icons {
    font-size: 2rem;
    color: var(--primary-blue);
}

.tool-card h4 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin-bottom: 1rem;
}

.tool-card p {
    color: var(--text-gray);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

/* Software Development */
.software-section {
    margin-bottom: 3rem;
}

.software-section h4 {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--primary-blue);
    margin-bottom: 1rem;
    text-align: center;
}

.software-description {
    text-align: center;
    color: var(--text-gray);
    font-size: 1.1rem;
    line-height: 1.6;
    margin-bottom: 2rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* Research Visualizations */
.visualization-section {
    margin-bottom: 3rem;
}

.visualization-section h4 {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--primary-blue);
    margin-bottom: 1.5rem;
    text-align: center;
}

.viz-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.viz-card {
    background: var(--background-white);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 8px 25px var(--shadow-light);
    transition: var(--transition);
}

.viz-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 35px var(--shadow-medium);
}

.viz-card img {
    width: 100%;
    height: 250px;
    object-fit: cover;
    cursor: pointer;
    transition: var(--transition);
}

.viz-card img:hover {
    transform: scale(1.05);
}

.viz-info {
    padding: 1.5rem;
}

.viz-info h5 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin-bottom: 0.5rem;
}

.viz-info p {
    color: var(--text-gray);
    line-height: 1.6;
    font-size: 0.9rem;
}

/* Published Works Section */
.published-works {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--background-light) 0%, var(--background-white) 100%);
}

.book-showcase {
    display: flex;
    justify-content: center;
    margin-bottom: 3rem;
}

.book-hero {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 4rem;
    max-width: 1100px;
    width: 100%;
    background: var(--background-white);
    border-radius: 24px;
    box-shadow: 0 20px 60px var(--shadow-medium);
    overflow: hidden;
    transition: var(--transition);
}

.book-hero:hover {
    transform: translateY(-8px);
    box-shadow: 0 30px 80px rgba(21, 101, 192, 0.2);
}

/* 3D Book Cover */
.book-cover-container {
    padding: 3rem 2rem;
    background: linear-gradient(135deg, var(--light-blue) 0%, var(--primary-blue) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.book-cover-3d {
    position: relative;
    transform-style: preserve-3d;
    transform: perspective(1000px) rotateY(-15deg);
    transition: var(--transition);
}

.book-cover-3d:hover {
    transform: perspective(1000px) rotateY(-5deg);
}

.book-cover-img {
    width: 240px;
    height: 320px;
    border-radius: 8px;
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.3);
    transition: var(--transition);
}

.book-spine {
    position: absolute;
    top: 0;
    right: -8px;
    width: 8px;
    height: 320px;
    background: linear-gradient(to bottom, #0D47A1, #1565C0);
    border-radius: 0 4px 4px 0;
    transform: rotateY(90deg);
    transform-origin: left;
}

/* Book Details */
.book-details {
    padding: 3rem 3rem 3rem 0;
}

.book-header {
    margin-bottom: 2.5rem;
}

.book-title-zh {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--dark-blue);
    margin-bottom: 0.5rem;
    line-height: 1.3;
}

.book-title-en {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--text-gray);
    font-style: italic;
    margin-bottom: 1.5rem;
}

.book-author {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.author-label {
    font-size: 0.9rem;
    color: var(--text-light);
    font-weight: 500;
}

.author-name {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--primary-blue);
}

.author-affiliation {
    font-size: 0.95rem;
    color: var(--text-gray);
}

/* Info Grid */
.book-info-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    margin-bottom: 2.5rem;
}

.info-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--light-blue);
    border-radius: 12px;
    transition: var(--transition);
}

.info-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px var(--shadow-light);
}

.info-icon {
    font-size: 1.5rem;
    width: 40px;
    text-align: center;
    color: var(--primary-blue);
}

.info-content {
    flex: 1;
}

.info-label {
    font-size: 0.85rem;
    color: var(--text-light);
    font-weight: 500;
    margin-bottom: 0.2rem;
}

.info-value {
    font-size: 0.95rem;
    color: var(--text-dark);
    font-weight: 600;
}

/* Modern Description */
.book-description-modern {
    margin-bottom: 2.5rem;
}

.description-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.description-header .material-icons {
    color: var(--primary-blue);
    font-size: 1.5rem;
}

.description-header h5 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin: 0;
}

.description-text {
    color: var(--text-gray);
    line-height: 1.8;
    font-size: 1.05rem;
    margin-bottom: 2rem;
}

.contents-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.8rem;
}

.content-item {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    padding: 0.8rem;
    background: rgba(21, 101, 192, 0.05);
    border-radius: 8px;
    border-left: 3px solid var(--primary-blue);
    transition: var(--transition);
}

.content-item:hover {
    background: rgba(21, 101, 192, 0.1);
    transform: translateX(5px);
}

.content-icon {
    font-size: 1.2rem;
    width: 30px;
    text-align: center;
    color: var(--primary-blue);
}

/* Purchase Button */
.book-actions {
    margin-top: 2rem;
}

.purchase-btn {
    display: inline-flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 2rem;
    background: linear-gradient(135deg, var(--primary-blue), var(--secondary-blue));
    color: white;
    text-decoration: none;
    border-radius: 12px;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: 0 8px 25px rgba(21, 101, 192, 0.3);
}

.purchase-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(21, 101, 192, 0.4);
    background: linear-gradient(135deg, var(--dark-blue), var(--primary-blue));
}

.btn-icon {
    font-size: 1.3rem;
}

.btn-text {
    font-size: 1.1rem;
}

.btn-subtext {
    font-size: 0.9rem;
    opacity: 0.9;
    font-weight: 400;
}

/* Members Section */
.members {
    padding: 80px 0;
    background: var(--background-light);
}

.members-category {
    margin-bottom: 4rem;
}

.members-category h3 {
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin-bottom: 2rem;
    padding-left: 1rem;
    border-left: 4px solid var(--accent-yellow);
}

.members-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.member-card {
    background: var(--background-white);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: 0 8px 25px var(--shadow-light);
    transition: var(--transition);
    text-align: center;
}

.member-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 35px var(--shadow-medium);
}

.member-card.placeholder {
    border: 2px dashed var(--primary-blue);
    background: rgba(21, 101, 192, 0.05);
}

.member-photo img {
    width: 120px;
    height: 144px;
    border-radius: 12px;
    object-fit: cover;
    margin-bottom: 1rem;
}

.member-info h4 {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--dark-blue);
    margin-bottom: 0.5rem;
}

.member-position {
    color: var(--primary-blue);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.member-research {
    color: var(--text-gray);
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.member-tags {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.alumni-list {
    display: grid;
    gap: 1.5rem;
}

.alumni-item {
    background: var(--background-white);
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px var(--shadow-light);
    border-left: 4px solid var(--accent-yellow);
}

.alumni-item h4 {
    color: var(--dark-blue);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.alumni-item p {
    color: var(--text-gray);
    margin-bottom: 0.3rem;
}

/* Publications Section */
.publications {
    padding: 80px 0;
    background: var(--background-white);
}

.publications-list {
    display: grid;
    gap: 2rem;
    margin-bottom: 3rem;
}

.publication-item {
    background: var(--background-light);
    padding: 2rem;
    border-radius: 12px;
    transition: var(--transition);
}

.publication-item:hover {
    box-shadow: 0 8px 25px var(--shadow-light);
}

.publication-item h4 {
    color: var(--dark-blue);
    font-weight: 600;
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.authors {
    color: var(--text-gray);
    margin-bottom: 0.3rem;
}

.journal {
    color: var(--primary-blue);
    margin-bottom: 1rem;
}

.publication-links {
    display: flex;
    gap: 0.5rem;
}

.view-all {
    text-align: center;
}

/* Contact Section */
.contact {
    padding: 80px 0;
    background: var(--background-light);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 2rem;
}

.contact-item .material-icons {
    color: var(--primary-blue);
    font-size: 1.5rem;
    margin-top: 0.2rem;
}

.contact-item h4 {
    color: var(--dark-blue);
    font-weight: 600;
    margin-bottom: 0.3rem;
}

.contact-item p {
    color: var(--text-gray);
}

.contact-form {
    background: var(--background-white);
    padding: 2.5rem;
    border-radius: 16px;
    box-shadow: 0 10px 30px var(--shadow-light);
}

.contact-form h3 {
    color: var(--dark-blue);
    font-weight: 600;
    margin-bottom: 2rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid rgba(21, 101, 192, 0.1);
    border-radius: 8px;
    font-family: inherit;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px rgba(21, 101, 192, 0.1);
}

/* Footer */
.footer {
    background: var(--dark-blue);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    color: var(--accent-yellow);
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: var(--transition);
}

.footer-section ul li a:hover {
    color: var(--accent-yellow);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
}

/* Responsive Design */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .directors-grid {
        grid-template-columns: 1fr;
    }

    .director-card {
        max-width: 500px;
        margin: 0 auto;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .research-grid,
    .members-grid {
        grid-template-columns: 1fr;
    }
    
    .research-highlights {
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
    }
    
    .tools-grid,
    .viz-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
    
    .book-hero {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .book-cover-container {
        padding: 2rem;
        text-align: center;
    }
    
    .book-cover-3d {
        transform: perspective(800px) rotateY(-10deg);
    }
    
    .book-cover-img {
        width: 200px;
        height: 267px;
    }
    
    .book-spine {
        height: 267px;
    }
    
    .book-details {
        padding: 2rem;
        text-align: center;
    }
    
    .book-info-grid {
        grid-template-columns: 1fr;
    }
    
    .contents-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .container {
        padding: 0 15px;
    }
    
    .research-highlights {
        grid-template-columns: 1fr;
    }
    
    .tools-grid,
    .viz-grid {
        grid-template-columns: 1fr;
    }
}