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

:root {
    --navy: #23297a;
    --white: #ffffff;
    --gray: #f8f8f8;
}

body {
    font-family: 'DM Sans', sans-serif;
    color: var(--navy);
    background: var(--white);
    line-height: 1.6;
}

/* Landing */
.landing {
    min-height: max(100vh, 1080px);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 4rem;
    padding: 4rem;
    background: var(--white);
}

.landing-content {
    max-width: 600px;
    flex: 1;
}

.landing-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.landing-image img {
    max-width: 100%;
    height: auto;
}

h1 {
    font-family: 'Cormorant Garamond', serif;
    font-size: 2.8rem;
    font-weight: 400;
    line-height: 1.1;
    margin-bottom: 0.25rem;
}

.subtitle {
    font-family: 'Cormorant Garamond', serif;
    font-size: 1.8rem;
    color: #9a9ab0;
    margin-bottom: 2rem;
}

.description {
    font-size: 1.1rem;
    max-width: 480px;
    margin-bottom: 2rem;
    opacity: 0.85;
}

.course-meta {
    font-size: 0.9rem;
    opacity: 0.6;
    display: flex;
    gap: 0.5rem;
}

/* Sections */
.section {
    min-height: 1080px;
    padding: 6rem 4rem;
    border-top: 1px solid rgba(35, 41, 122, 0.1);
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.section-number {
    font-family: 'Cormorant Garamond', serif;
    font-size: 0.9rem;
    opacity: 0.4;
    margin-bottom: 1rem;
}

h2 {
    font-family: 'Cormorant Garamond', serif;
    font-size: 2.5rem;
    font-weight: 400;
    margin-bottom: 2rem;
}

.section-content {
    max-width: 720px;
}

.section-content p {
    margin-bottom: 1.5rem;
    opacity: 0.85;
}

/* Method Phases */
.method-phases {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    max-width: 1200px;
}

.phase-title {
    font-family: 'Cormorant Garamond', serif;
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
}

.steps {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.step {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.step-number {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    opacity: 0.5;
}

.step strong {
    font-family: 'Cormorant Garamond', serif;
    font-size: 1.15rem;
    font-weight: 600;
}

.step p {
    font-size: 0.9rem;
    opacity: 0.8;
    margin: 0;
    line-height: 1.5;
}

/* Deliverable List */
.deliverable-list {
    list-style: none;
}

.deliverable-list li {
    padding: 1.25rem 0;
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.deliverable-list strong {
    font-weight: 500;
}

.deliverable-list span {
    font-size: 0.9rem;
    opacity: 0.6;
}

/* Video Background Section */
.section-video {
    position: relative;
    overflow: hidden;
}

.section-video video {
    position: absolute;
    top: 50%;
    left: 50%;
    min-width: 100%;
    min-height: 100%;
    transform: translate(-50%, -50%);
    object-fit: cover;
    z-index: 0;
}

.section-video .video-overlay {
    position: absolute;
    inset: 0;
    background: rgba(35, 41, 122, 0.9);
    z-index: 1;
}

.section-video-content {
    position: relative;
    z-index: 2;
}

.section-video .section-number,
.section-video h2,
.section-video .phase-title,
.section-video .step-number,
.section-video .step strong,
.section-video .step p {
    color: var(--white);
}

.section-video .section-number {
    opacity: 0.6;
}

/* Image Stack with Viewer */
.section-image-stack {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 1.5rem;
    margin-left: -10rem;
    margin-top: 10rem;
}

.collage-container {
    position: relative;
    max-width: 80%;
}

.collage-container img {
    width: 100%;
    height: auto;
}

.hotspot {
    position: absolute;
    width: 40px;
    height: 40px;
    border: none;
    background: transparent;
    cursor: pointer;
    border-radius: 50%;
    transition: all 0.3s ease;
}

.hotspot:hover {
    background: rgba(35, 41, 122, 0.2);
    transform: scale(1.2);
}

/* 왼쪽 위 - space2 */
.hotspot-1 {
    top: 10%;
    left: 42.5%;
}

/* 오른쪽 위 - space3 */
.hotspot-2 {
    top: 10%;
    left: 58.5%;
}

/* 아래 - space1 */
.hotspot-3 {
    top: 42%;
    left: 42.5%;
}


.inline-video {
    width: 80%;
}

.inline-video video {
    width: 100%;
    height: auto;
    border: 1px solid rgba(35, 41, 122, 0.2);
}

.caption {
    font-size: 0.8rem;
    opacity: 0.5;
    margin-top: 0.5rem;
    font-style: italic;
}

/* Fade-in Animations */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* Keep specific opacity for elements that need it */
.fade-in.visible.section-number {
    opacity: 0.4;
}

.fade-in.visible.course-meta {
    opacity: 0.6;
}

.fade-in.visible.caption {
    opacity: 0.5;
}

.fade-in.visible.description,
.fade-in.visible.section-content p,
.fade-in.visible .step p {
    opacity: 0.85;
}

.fade-in.visible.deliverable-list span {
    opacity: 0.6;
}

/* About Section */
.section-about {
    flex-direction: row;
    align-items: flex-start;
    gap: 4rem;
}

.about-left {
    flex: 1;
    max-width: 500px;
}

.about-left h2 {
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

.about-bio {
    font-size: 0.95rem;
    line-height: 1.8;
    opacity: 0.85;
}

.about-right {
    flex: 1;
    padding-top: 5.5rem;
}

.about-research {
    margin-bottom: 2rem;
}

.about-research h3,
.about-papers h3 {
    font-family: 'Cormorant Garamond', serif;
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--navy);
}

.about-research p {
    font-size: 0.9rem;
    opacity: 0.7;
}

.about-papers {
    margin-bottom: 2.5rem;
}

.about-papers ul {
    list-style: none;
}

.about-papers li {
    display: flex;
    gap: 1rem;
    padding: 0.75rem 0;
    border-bottom: 1px solid rgba(35, 41, 122, 0.1);
}

.paper-year {
    font-family: 'Cormorant Garamond', serif;
    font-size: 0.9rem;
    font-weight: 600;
    opacity: 0.5;
    flex-shrink: 0;
}

.paper-title {
    font-size: 0.85rem;
    line-height: 1.5;
    opacity: 0.8;
}

/* Viewer Section */
.section-viewer {
    padding: 4rem;
    align-items: center;
    background: #000000;
}

.section-viewer iframe {
    width: 120%;
    height: 950px;
    border: 1px solid rgba(35, 41, 122, 0.2);
    overflow: hidden;
}

/* Hide iframe scrollbars */
.section-viewer {
    overflow: hidden;
}

/* Selective Section */
.section-selective {
    background: var(--white);
}

.selective-title {
    font-size: 3rem;
    font-weight: 400;
    margin-bottom: 1rem;
}

.title-gray {
    color: #9a9ab0;
}

.title-colon {
    color: #9a9ab0;
}

.title-blue {
    color: var(--navy);
}

.selective-subtitle {
    font-size: 1rem;
    opacity: 0.6;
    margin-bottom: 3rem;
}

.selective-content {
    max-width: 700px;
    text-align: center;
    margin-bottom: 4rem;
}

.selective-content p {
    font-size: 0.95rem;
    line-height: 1.7;
    opacity: 0.8;
    margin-bottom: 1rem;
}

.instructors {
    display: flex;
    gap: 4rem;
    max-width: 1000px;
}

.instructor {
    flex: 1;
    text-align: left;
}

.instructor h3 {
    font-family: 'Cormorant Garamond', serif;
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.instructor-title {
    font-size: 0.85rem;
    opacity: 0.5;
    margin-bottom: 1rem;
}

.instructor-bio {
    font-size: 0.9rem;
    line-height: 1.6;
    opacity: 0.75;
}

/* Centered Section */
.section-centered {
    align-items: center;
    justify-content: center;
}

.partners-title {
    font-size: 1.2rem;
    font-weight: 400;
    color: #9a9ab0;
    margin-bottom: 1.5rem;
}

.partners-image {
    max-width: 800px;
}

.partners-image img {
    width: 100%;
    height: auto;
}

.footer-meta {
    position: absolute;
    bottom: 15rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

/* Footer */
footer {
    padding: 3rem 4rem;
    text-align: center;
    font-size: 0.85rem;
    opacity: 0.5;
    border-top: 1px solid rgba(35, 41, 122, 0.1);
}

/* Split Section */
.section-split {
    flex-direction: row;
    align-items: center;
    gap: 4rem;
}

.section-text {
    flex: 1;
}

.section-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.section-image img {
    max-width: 100%;
    height: auto;
}

/* Responsive */
@media (max-width: 768px) {
    .landing, .section {
        padding: 3rem 2rem;
    }
    
    .landing {
        flex-direction: column;
        gap: 2rem;
    }
    
    h1 { font-size: 2.5rem; }
    .subtitle { font-size: 2rem; }
    h2 { font-size: 2rem; }
    
    .method-phases {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
    
    .section-split {
        flex-direction: column;
        gap: 2rem;
    }
}