:root[data-theme="light"] {
    --bg-color: #f8fafc; /* Light background */
    --text-primary: #0f172a;
    --text-secondary: #475569;
    
    --accent-primary: #0284c7; /* Blue from logo */
    --accent-secondary: #0ea5e9; /* Light blue */
    --accent-tertiary: #10b981; /* Green from logo */
    
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(0, 0, 0, 0.05);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.05);
    
    --card-hover-bg: rgba(255, 255, 255, 0.9);
    --card-hover-border: rgba(0, 0, 0, 0.1);
    --icon-color: rgba(0, 0, 0, 0.05);
    --icon-hover-color: rgba(0, 0, 0, 0.1);
    
    --course-bg-gradient: linear-gradient(135deg, rgba(255, 255, 255, 0.8) 0%, rgba(255, 255, 255, 0.4) 100%);
    
    --btn-sec-bg: rgba(0, 0, 0, 0.05);
    --btn-sec-hover: rgba(0, 0, 0, 0.1);
    
    --transition: all 0.3s ease;
}

:root {
    --bg-color: #0f172a; /* Deep blue/gray dark mode */
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    
    --accent-primary: #3b82f6; /* Blue */
    --accent-secondary: #8b5cf6; /* Purple */
    --accent-tertiary: #10b981; /* Green */
    
    --glass-bg: rgba(30, 41, 59, 0.4);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
    
    --card-hover-bg: rgba(30, 41, 59, 0.6);
    --card-hover-border: rgba(255, 255, 255, 0.15);
    --icon-color: rgba(255, 255, 255, 0.05);
    --icon-hover-color: rgba(255, 255, 255, 0.1);
    
    --course-bg-gradient: linear-gradient(135deg, rgba(30, 41, 59, 0.6) 0%, rgba(30, 41, 59, 0.2) 100%);
    
    --btn-sec-bg: rgba(255, 255, 255, 0.05);
    --btn-sec-hover: rgba(255, 255, 255, 0.1);
}

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

body {
    font-family: 'Outfit', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
    min-height: 100vh;
}

h1, h2, h3, h4 {
    font-family: 'Playfair Display', serif;
    font-weight: 600;
}

/* Background Animation */
.background-elements {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    overflow: hidden;
}

.blob {
    position: absolute;
    filter: blur(90px);
    opacity: 0.5;
    animation: float 20s infinite alternate;
}

.blob-1 {
    top: -10%;
    left: -10%;
    width: 50vw;
    height: 50vw;
    background: radial-gradient(circle, var(--accent-primary) 0%, transparent 70%);
}

.blob-2 {
    bottom: -10%;
    right: -10%;
    width: 60vw;
    height: 60vw;
    background: radial-gradient(circle, var(--accent-secondary) 0%, transparent 70%);
    animation-delay: -5s;
}

.blob-3 {
    top: 40%;
    left: 30%;
    width: 40vw;
    height: 40vw;
    background: radial-gradient(circle, var(--accent-tertiary) 0%, transparent 70%);
    opacity: 0.3;
    animation-duration: 25s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(50px, 50px) scale(1.1); }
}

/* Layout */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
}

/* Header */
header {
    position: sticky;
    top: 0;
    z-index: 100;
    padding: 1rem 0;
    border-radius: 0 0 24px 24px;
    margin-bottom: 3rem;
    border-top: none;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem;
    border-radius: 50%;
    transition: var(--transition);
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
}

.theme-toggle:hover {
    transform: scale(1.1);
    background: var(--card-hover-bg);
}

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

.logo {
    height: 60px;
    border-radius: 12px;
    transition: var(--transition);
}

.logo:hover {
    transform: scale(1.05);
}

.construction-badge {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(245, 158, 11, 0.1);
    color: #fcd34d;
    padding: 0.5rem 1rem;
    border-radius: 99px;
    font-size: 0.9rem;
    font-weight: 600;
    border: 1px solid rgba(245, 158, 11, 0.2);
}

.pulse-dot {
    width: 10px;
    height: 10px;
    background-color: #f59e0b;
    border-radius: 50%;
    box-shadow: 0 0 0 0 rgba(245, 158, 11, 0.7);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(245, 158, 11, 0.7); }
    70% { box-shadow: 0 0 0 10px rgba(245, 158, 11, 0); }
    100% { box-shadow: 0 0 0 0 rgba(245, 158, 11, 0); }
}

/* Hero */
.hero {
    padding: 4rem 3rem;
    border-radius: 32px;
    text-align: center;
    margin-bottom: 4rem;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero h1 span {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

.intro-text {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto;
}

/* Purposes */
.purpose-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 5rem;
}

.purpose-card {
    padding: 2.5rem 2rem;
    border-radius: 24px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.purpose-card:hover {
    transform: translateY(-10px);
    background: var(--card-hover-bg);
    border-color: var(--card-hover-border);
}

.card-icon {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--icon-color);
    position: absolute;
    top: -10px;
    right: 10px;
    transition: var(--transition);
}

.purpose-card:hover .card-icon {
    color: var(--icon-hover-color);
    transform: scale(1.1);
}

.card-content {
    position: relative;
    z-index: 1;
}

.card-content h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--accent-primary);
}

.card-content p {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* Course Section */
.course-section {
    margin-bottom: 5rem;
}

.course-container {
    display: flex;
    flex-direction: column;
    gap: 3rem;
    padding: 3rem;
    border-radius: 32px;
    background: var(--course-bg-gradient);
    align-items: center;
}

.course-content {
    display: flex;
    gap: 4rem;
    align-items: center;
    width: 100%;
}

.course-collaborator {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.25rem;
    text-align: center;
    width: 100%;
}

.collaborator-logo {
    max-width: 280px;
    width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
    border: 1px solid var(--glass-border);
}

.collaborator-logo:hover {
    transform: scale(1.03);
}

.collaborator-info {
    font-size: 0.8rem;
    color: var(--text-secondary);
    max-width: 750px;
    line-height: 1.6;
    opacity: 0.8;
}

.course-visual {
    flex: 1;
    max-width: 400px;
}

.course-poster {
    width: 100%;
    border-radius: 16px;
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.5);
    transition: var(--transition);
    border: 1px solid var(--glass-border);
}

.course-poster:hover {
    transform: scale(1.03) rotate(-1deg);
}

.course-details {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.tag {
    display: inline-block;
    background: rgba(16, 185, 129, 0.1);
    color: var(--accent-tertiary);
    padding: 0.5rem 1rem;
    border-radius: 99px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 1rem;
    align-self: flex-start;
    border: 1px solid rgba(16, 185, 129, 0.2);
}

.course-details h2 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.course-details p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
}

.actions {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 1rem 2rem;
    border-radius: 99px;
    font-weight: 600;
    font-size: 1.1rem;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
}

.btn-primary {
    background: var(--accent-primary);
    color: white;
    box-shadow: 0 10px 20px -10px var(--accent-primary);
}

.btn-primary:hover {
    background: #2563eb;
    transform: translateY(-3px);
    box-shadow: 0 15px 25px -10px var(--accent-primary);
}

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

.btn-secondary:hover {
    background: var(--btn-sec-hover);
    transform: translateY(-3px);
}

/* Footer */
footer {
    padding: 2rem 0;
    text-align: center;
    border-radius: 24px 24px 0 0;
    margin-top: 4rem;
    border-bottom: none;
}

.footer-content p {
    color: var(--text-secondary);
}

/* Animations */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 0.8s forwards ease-out;
}

.delay-1 { animation-delay: 0.2s; }
.delay-2 { animation-delay: 0.4s; }

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

/* Responsive */
@media (max-width: 900px) {
    .course-content {
        flex-direction: column;
        gap: 2rem;
    }
    
    .course-container {
        padding: 2rem;
        gap: 2.5rem;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .course-details h2 {
        font-size: 2.2rem;
    }
}

@media (max-width: 600px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .actions {
        flex-direction: column;
        width: 100%;
    }
    
    .btn {
        width: 100%;
    }
}