:root {
    --bg-color: #05050f;
    --card-bg: rgba(20, 20, 35, 0.6);
    --card-border: rgba(255, 255, 255, 0.1);
    --text-main: #ffffff;
    --text-muted: #a0a0b8;
    --primary: #8b5cf6;
    --primary-hover: #7c3aed;
    --secondary: #0ea5e9;
    --accent: #22d3ee;
    --gradient-primary: linear-gradient(135deg, #8b5cf6 0%, #0ea5e9 100%);
    --font-family: 'Pretendard', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Glassmorphism Utilities */
.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--card-border);
    border-radius: 20px;
    padding: 2.5rem;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease, border-color 0.3s ease;
    position: relative;
    z-index: 1;
}

.glass-card:hover {
    transform: translateY(-5px);
    border-color: rgba(139, 92, 246, 0.5);
    z-index: 10;
}

.text-neon {
    color: var(--accent);
    text-shadow: 0 0 10px rgba(34, 211, 238, 0.5);
}

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

/* Buttons */
.btn-primary, .btn-secondary, .btn-primary-small {
    display: inline-block;
    padding: 0.8rem 1.8rem;
    border-radius: 50px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.4);
}

.btn-primary:hover {
    box-shadow: 0 6px 20px rgba(139, 92, 246, 0.6);
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: var(--text-main);
    border: 1px solid var(--card-border);
    backdrop-filter: blur(5px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: var(--text-main);
}

.btn-primary-small {
    padding: 0.5rem 1.2rem;
    font-size: 0.9rem;
    background: var(--gradient-primary);
    color: white;
}

.btn-large {
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
}

.btn-ghost {
    display: inline-block;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    background: transparent;
    color: var(--text-muted);
    border: 1px solid transparent;
    font-size: 1.1rem;
}

.btn-ghost:hover {
    color: var(--text-main);
    background: rgba(255, 255, 255, 0.05);
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: 15px 0;
    z-index: 100;
    background: rgba(5, 5, 15, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.2rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.gnb {
    display: flex;
    gap: 2.5rem;
}

.gnb a {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: color 0.3s ease;
}

.gnb a:hover {
    color: var(--text-main);
}

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

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('assets/hero-bg.png');
    background-size: cover;
    background-position: center;
    opacity: 0.4;
    z-index: -1;
}

.hero-bg::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, rgba(5,5,15,0.2) 0%, rgba(5,5,15,1) 100%);
}

.hero-content {
    max-width: 800px;
    text-align: left;
}

.badge {
    display: inline-block;
    padding: 0.4rem 1rem;
    border-radius: 50px;
    background: rgba(34, 211, 238, 0.1);
    color: var(--accent);
    border: 1px solid rgba(34, 211, 238, 0.3);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
}

.hero .title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 1rem;
}

.hero .highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero .subtitle {
    font-size: 1.8rem;
    font-weight: 300;
    color: var(--text-muted);
    margin-bottom: 2rem;
}

.hero .desc {
    font-size: 1.1rem;
    color: var(--text-muted);
    margin-bottom: 2.5rem;
    max-width: 600px;
}

.cta-group {
    display: flex;
    gap: 1rem;
}

/* Sections Common */
section {
    padding: 5rem 0;
}

.section-title {
    font-size: 2.2rem;
    margin-bottom: 3rem;
    font-weight: 700;
}

.section-title i {
    margin-right: 12px;
}

/* Mentor Section */
.mentor-card {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 3rem;
}

.mentor-profile {
    flex-shrink: 0;
}

.mentor-avatar {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid rgba(139, 92, 246, 0.5);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5);
    background-color: rgba(20, 20, 35, 0.8);
}

.mentor-info {
    flex: 1;
}

.mentor-info h3 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.mentor-info .role {
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 2rem;
    font-size: 1.1rem;
}

.mentor-list {
    list-style: none;
}

.mentor-list li {
    margin-bottom: 1rem;
    font-size: 1.1rem;
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.mentor-list i {
    margin-top: 5px;
}

/* Motivation Section */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 3rem;
}

.icon-box {
    width: 60px;
    height: 60px;
    border-radius: 15px;
    background: rgba(139, 92, 246, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    color: var(--primary);
    margin-bottom: 1.5rem;
}

.quote-box {
    text-align: center;
    padding: 3rem;
    border-radius: 20px;
    background: linear-gradient(rgba(20,20,35,0.8), rgba(20,20,35,0.8)), url('assets/hero-bg.png');
    background-size: cover;
    background-position: center;
    border: 1px solid var(--card-border);
}

.quote-box p {
    font-size: 1.5rem;
    font-weight: 600;
    font-style: italic;
    margin-bottom: 1rem;
}

.quote-box span {
    color: var(--text-muted);
}

/* Details Section */
.details-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    text-align: center;
}

.detail-item {
    padding: 2rem;
    background: rgba(255,255,255,0.03);
    border-radius: 20px;
    border: 1px solid rgba(255,255,255,0.05);
}

.detail-item i {
    font-size: 2.5rem;
    color: var(--accent);
    margin-bottom: 1.5rem;
}

.detail-item h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

.detail-item p {
    color: var(--text-muted);
}

/* Curriculum Section */
.timeline {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 40px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--gradient-primary);
    opacity: 0.3;
}

.timeline-item {
    position: relative;
    padding-left: 80px;
    display: flex;
    align-items: flex-start;
}

.week-badge {
    position: absolute;
    left: 15px;
    top: 2.5rem;
    background: var(--gradient-primary);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.9rem;
    box-shadow: 0 0 15px rgba(139, 92, 246, 0.5);
    z-index: 2;
}

.timeline-content h3 {
    font-size: 1.4rem;
    margin-bottom: 0.8rem;
    color: var(--primary);
}

.timeline-content p {
    color: var(--text-muted);
}

/* Activity Section */
.section-desc {
    text-align: center;
    color: var(--text-muted);
    margin-top: -1.5rem;
    margin-bottom: 3rem;
    font-size: 1.1rem;
}

.media-gallery {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.media-item {
    padding: 0;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    aspect-ratio: 4/3;
}

.media-item img, .media-item video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.media-item:hover img, .media-item:hover video {
    transform: scale(1.05);
}

.testimonials {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-top: 3rem;
}

.testimonial-card {
    padding: 2rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.testimonial-card .stars {
    color: #fbbf24;
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.testimonial-card .review-text {
    font-size: 1.1rem;
    font-style: italic;
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.testimonial-card .reviewer {
    text-align: right;
    color: var(--text-muted);
    font-size: 1rem;
}

.testimonial-card .reviewer strong {
    color: var(--primary);
    margin-left: 5px;
    font-size: 1.1rem;
}

/* Tooltip Styles */
.has-tooltip {
    position: relative;
    cursor: pointer;
    display: inline-block;
}

.result-badge {
    display: inline-block;
    background: rgba(34, 211, 238, 0.15);
    border: 1px solid rgba(34, 211, 238, 0.4);
    color: var(--accent);
    padding: 0.2rem 0.6rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-left: 10px;
    transition: all 0.3s ease;
}

.has-tooltip:hover .result-badge {
    background: rgba(34, 211, 238, 0.3);
    border-color: var(--accent);
}

.tooltip {
    visibility: hidden;
    opacity: 0;
    position: absolute;
    bottom: 130%;
    left: 50%;
    transform: translateX(-50%) translateY(10px);
    width: 280px;
    background: rgba(15, 15, 25, 0.95);
    border: 1px solid rgba(139, 92, 246, 0.5);
    border-radius: 10px;
    padding: 10px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.8);
    transition: all 0.3s ease;
    z-index: 50;
    text-align: center;
    backdrop-filter: blur(10px);
}

.tooltip::after {
    content: '';
    position: absolute;
    top: 100%;
    left: 50%;
    margin-left: -8px;
    border-width: 8px;
    border-style: solid;
    border-color: rgba(139, 92, 246, 0.5) transparent transparent transparent;
}

.tooltip img {
    width: 100%;
    border-radius: 5px;
    margin-bottom: 8px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3);
}

.tooltip p {
    font-size: 0.85rem;
    color: var(--text-main);
    margin: 0;
    font-weight: 600;
}

.has-tooltip:hover .tooltip, .has-tooltip.active .tooltip {
    visibility: visible;
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* Apply Section */
.apply-card {
    border: 2px solid rgba(139, 92, 246, 0.3);
    background: rgba(20, 20, 35, 0.8);
}

.apply-info {
    list-style: none;
    margin: 2rem 0;
    padding: 2rem;
    background: rgba(0,0,0,0.3);
    border-radius: 15px;
}

.apply-info li {
    margin-bottom: 1.2rem;
    font-size: 1.1rem;
}

.apply-info li:last-child {
    margin-bottom: 0;
}

.apply-info strong {
    color: var(--accent);
    display: inline-block;
    width: 80px;
}

.apply-buttons {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 2rem;
}

/* Footer */
.footer {
    padding: 2rem 0;
    border-top: 1px solid rgba(255,255,255,0.05);
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Animations */
.slide-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.slide-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 768px) {
    .gnb {
        display: none;
    }
    .hero .title {
        font-size: 2.5rem;
    }
    .hero .subtitle {
        font-size: 1.3rem;
    }
    .mentor-card {
        flex-direction: column;
        text-align: center;
        gap: 1.5rem;
    }
    .mentor-list li {
        text-align: left;
    }
    .grid-2, .details-grid, .media-gallery, .testimonials {
        grid-template-columns: 1fr;
    }
    .apply-buttons {
        flex-direction: column;
    }
    .cta-group {
        flex-direction: column;
    }
    .timeline::before {
        left: 20px;
    }
    .timeline-item {
        padding-left: 60px;
    }
    .week-badge {
        left: -5px;
        width: 40px;
        height: 40px;
        font-size: 0.8rem;
    }
}