:root {
    /* Light Theme Colors */
    --bg-light: #f8fafc; /* Slate 50 */
    --bg-lighter: #ffffff; /* pure white */
    --text-main: #0f172a; /* Slate 900 */
    --text-muted: #475569; /* Slate 600 */
    --primary: #10b981; /* Emerald 500 */
    --primary-dark: #059669; /* Emerald 600 */
    --primary-light: #d1fae5; /* Emerald 100 */
    --card-bg: rgba(255, 255, 255, 0.9);
    --card-border: rgba(0, 0, 0, 0.05);
    
    /* Shadows for depth */
    --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.025);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    --font-bengali: 'Hind Siliguri', sans-serif;
    --transition: all 0.3s ease;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { 
    font-family: var(--font-bengali); 
    background: var(--bg-light); 
    color: var(--text-main); 
    line-height: 1.6; 
    overflow-x: hidden; 
}
a { text-decoration: none; color: var(--text-main); transition: var(--transition); }
ul { list-style: none; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 2rem; }
.text-center { text-align: center; }
.mx-auto { margin-left: auto; margin-right: auto; }
.highlight { color: var(--primary); }
h1, h2, h3, h4 { font-weight: 700; margin-bottom: 1rem; color: var(--text-main); }
p { color: var(--text-muted); margin-bottom: 1rem; }

.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.1rem;
    cursor: pointer;
    transition: var(--transition);
    text-transform: uppercase;
    letter-spacing: 1px;
}
.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3);
    border: none;
}
.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(16, 185, 129, 0.4);
    color: #fff;
}

/* Navbar */
.navbar { position: fixed; top: 0; width: 100%; z-index: 1000; padding: 1.5rem 0; transition: var(--transition); }
.navbar.scrolled { 
    background: rgba(255, 255, 255, 0.95); 
    backdrop-filter: blur(10px); 
    padding: 1rem 0; 
    border-bottom: 1px solid var(--card-border); 
    box-shadow: var(--shadow-sm);
}
.nav-container { display: flex; justify-content: space-between; align-items: center; max-width: 1200px; margin: 0 auto; padding: 0 2rem;}
.logo { font-size: 1.8rem; font-weight: 700; color: var(--primary); display: flex; align-items: center; gap: 0.5rem; }
.nav-links { display: flex; gap: 2rem; }
.nav-links a { font-weight: 600; font-size: 1.1rem; position: relative; }
.nav-links a:hover { color: var(--primary); }

/* Hero Section */
.hero { position: relative; min-height: 100vh; display: flex; align-items: center; justify-content: center; text-align: center; padding: 8rem 2rem 4rem; overflow: hidden; z-index: 1; }
.hero-bg-elements { position: absolute; top: 0; left: 0; width: 100%; height: 100%; z-index: -1; background: radial-gradient(circle at center, var(--bg-lighter), var(--bg-light)); overflow: hidden; }
.glow-orb { position: absolute; border-radius: 50%; filter: blur(80px); opacity: 0.6; }
.orb-1 { width: 400px; height: 400px; background: rgba(16, 185, 129, 0.2); top: -50px; left: -100px; }
.orb-2 { width: 500px; height: 500px; background: rgba(245, 158, 11, 0.15); bottom: -100px; right: -100px; }

.badge {
    display: inline-block;
    padding: 0.5rem 1.5rem;
    background: var(--primary-light);
    border: 1px solid var(--primary);
    color: var(--primary-dark);
    border-radius: 50px;
    margin-bottom: 2rem;
    font-weight: 600;
    letter-spacing: 1px;
}
.hero-title { font-size: 4rem; margin-bottom: 1.5rem; line-height: 1.2; color: #0f172a; }
.hero-subtitle { font-size: 1.25rem; margin-bottom: 2.5rem; max-width: 800px; margin-left: auto; margin-right: auto; color: var(--text-muted); }

/* Sections */
.section { padding: 5rem 0; position: relative; }
.bg-alt { background-color: var(--bg-lighter); }
.section-header { margin-bottom: 3rem; }
.section-header h2 { font-size: 2.5rem; color: var(--text-main); }
.divider { width: 80px; height: 4px; background: linear-gradient(90deg, var(--primary), transparent); border-radius: 2px; margin-bottom: 2rem; }

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

/* Cards */
.card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 20px;
    padding: 2.5rem;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}
.glass-card { backdrop-filter: blur(12px); background: rgba(255, 255, 255, 0.6); }
.card:hover {
    transform: translateY(-10px);
    border-color: rgba(16, 185, 129, 0.2);
    box-shadow: var(--shadow-lg);
}
.card-icon { font-size: 2.5rem; color: var(--primary); margin-bottom: 1.5rem; }
.feature-card i { font-size: 3rem; color: #f59e0b; margin-bottom: 1.5rem; display: inline-block; }

/* Lists */
.feature-list { margin-top: 2rem; }
.feature-list li { margin-bottom: 1rem; display: flex; align-items: flex-start; gap: 1rem; font-size: 1.1rem; color: var(--text-main); }
.feature-list i { color: var(--primary); margin-top: 5px; }

/* Stats */
.stats-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; }
.stat-card {
    background: linear-gradient(135deg, rgba(255, 255, 255, 1), rgba(255, 255, 255, 0.8));
    border: 1px solid rgba(16, 185, 129, 0.1);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}
.stat-card:hover { transform: scale(1.05); box-shadow: var(--shadow-md); }
.stat-number { font-size: 3rem; color: var(--primary); margin-bottom: 0.5rem; }

/* Gallery */
.gallery-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 2rem; }
.gallery-item {
    position: relative;
    border-radius: 20px;
    height: 250px;
    display: flex;
    align-items: flex-end;
    padding: 1.5rem;
    overflow: hidden;
    background: #f1f5f9;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}
.gallery-item:hover { transform: translateY(-8px); box-shadow: var(--shadow-lg); }

/* Patterns for Light Theme */
.card-pattern-1 { background: radial-gradient(circle at right top, rgba(16, 185, 129, 0.15), transparent 60%), #ffffff; }
.card-pattern-2 { background: radial-gradient(circle at left bottom, rgba(245, 158, 11, 0.15), transparent 60%), #ffffff; }
.card-pattern-3 { background: radial-gradient(circle at center, rgba(59, 130, 246, 0.15), transparent 60%), #ffffff; }
.card-pattern-4 { background: radial-gradient(circle at top left, rgba(236, 72, 153, 0.15), transparent 60%), #ffffff; }

.gallery-content {
    position: relative;
    z-index: 2;
    width: 100%;
    background: rgba(255, 255, 255, 0.85);
    padding: 1rem;
    border-radius: 12px;
    backdrop-filter: blur(5px);
    box-shadow: var(--shadow-sm);
}
.gallery-content h4 { color: #0f172a; margin-bottom: 0.3rem; font-size: 1.2rem; }
.gallery-content p { color: var(--text-muted); font-size: 0.95rem; margin-bottom: 0; line-height: 1.4; }

/* Info card */
.icon-wrapper {
    width: 70px;
    height: 70px;
    background: var(--primary-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: var(--primary-dark);
    margin-bottom: 1.5rem;
}

/* Footer */
.footer { background: #f1f5f9; padding: 4rem 0 2rem; border-top: 1px solid #e2e8f0; }
.footer-bottom { border-top: 1px solid #cbd5e1; padding-top: 2rem; color: var(--text-muted); margin-top: 2rem; }

@media (max-width: 768px) {
    .grid-2, .grid-3, .stats-grid { grid-template-columns: 1fr; }
    .hero-title { font-size: 2.5rem; }
    .nav-links { display: none; }
    .hero { padding-top: 10rem; }
}