:root {
    --bg-dark: #000000; 
    --nav-dark: rgba(10, 10, 10, 0.95);
    --text-light: #f1f1f1;
    --text-muted: #b2bec3;
    --primary: #ff7675;
    
    --p-orange: #ffccbc; 
    --p-blue: #b2ebf2;   
    --p-purple: #d1c4e9; 
    --p-yellow: #fff9c4; 
    --p-green: #c8e6c9;  
    --p-red: #ffcdd2;    
}

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



body {
    font-family: 'Poppins', 'Noto Sans Sinhala', sans-serif;
    background-color: var(--bg-light);
    color: var(--text-dark);
    overflow-x: hidden;
    width: 100%;
}

#particles-container {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    z-index: 1; pointer-events: none;
}

.particle { 
    position: absolute; border-radius: 50%; opacity: 0; 
    animation: particle-anim 12s infinite linear; filter: blur(1px);
}

@keyframes particle-anim {
    0% { transform: translate(0, 0) scale(0); opacity: 0; }
    20% { opacity: 0.5; }
    80% { opacity: 0.5; }
    100% { transform: translate(var(--x), var(--y)) scale(1.5); opacity: 0; }
}

.page-wrapper { position: relative; z-index: 10; width: 100%; }

nav {
    padding: 15px 5%;
    display: flex; justify-content: space-between; align-items: center;
    background: var(--nav-light);
    backdrop-filter: blur(15px);
    position: absolute; top: 0; width: 100%; z-index: 1000;
    border-bottom: 1px solid rgba(0,0,0,0.05);
}

.logo { font-size: 1.4rem; font-weight: 800; color: var(--text-dark); text-decoration: none; letter-spacing: 1px; }
.logo span { color: var(--primary); }

.hero {
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 120px 20px 60px;
    position: relative;
    background-image: linear-gradient(rgba(255, 255, 255, 0.603), rgba(255, 255, 255, 0.658)), url(science-lab-glassware-microscope.jpg);
    background-attachment: fixed; 
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
}

.hero-content { position: relative; z-index: 5; max-width: 950px; }

.hero h1 {
    font-size: clamp(2.5rem, 8vw, 4.2rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 25px;
    color: #2d3436;
    animation: fadeInUp 0.8s ease;
}

.hero h1 span { color: var(--primary); }

.hero p {
    font-size: clamp(1rem, 3vw, 1.2rem);
    color: #636e72;
    max-width: 750px;
    margin: 0 auto 45px;
    line-height: 1.6;
    animation: fadeInUp 1s ease;
}

.instructor-btn {
    background: rgba(243, 163, 176, 0);
    color: rgb(107, 34, 34);
    padding: 18px 35px;
    border-radius: 100px;
    text-decoration: none;
    font-weight: 700;
    display: inline-flex;
    align-items: center;
    gap: 12px;
    transition: 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    box-shadow: 0 10px 25px rgba(74, 63, 224, 0.3);
    border: 2px solid transparent;
    animation: fadeInUp 1.2s ease;
}

.instructor-btn:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(255, 118, 117, 0.4);
    background: white;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.instructor-btn i { font-size: 1.2rem; }
.instructor-btn .uni-detail { font-weight: 400; font-size: 0.85rem; opacity: 0.9; }

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.sample-section {
    padding: 80px 5%;
    text-align: center;
}

.sample-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 25px;
    margin-top: 40px;
}

.sample-title {
    color: var(--p-blue);
    font-size: 1.8rem;
    margin-bottom: 10px;
    font-weight: 700;
}

.sample-card {
    background-color: var(--p-blue);
    flex: 1;
    min-width: 300px;
    max-width: 380px;
    padding: 35px;
    border-radius: 40px;
    color: #1a1a1a;
    box-shadow: 0 15px 40px rgba(178, 235, 242, 0.2);
    position: relative;
    text-align: center;
    transition: 0.3s;
}

.sample-card:hover { transform: translateY(-10px); }

.badge {
    background: rgba(0,0,0,0.1);
    padding: 5px 12px;
    border-radius: 10px;
    font-size: 0.7rem;
    font-weight: 800;
    display: inline-block;
    margin-bottom: 15px;
}

.btn-stack {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 20px;
}

.btn-primary {
    background: #2d3436;
    color: white;
    padding: 14px 28px; 
    border-radius: 18px;
    text-decoration: none;
    font-weight: 700;
    font-size: 0.9rem;
    display: inline-block; 
    transition: 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-3px);
    background: #a2d2ff; 
    color: #2d3436;     
    box-shadow: 0 10px 20px rgba(162, 210, 255, 0.3); 
}

.btn-secondary {
    background: white;
    color: #2d3436;
    padding: 14px;
    border-radius: 18px;
    text-decoration: none;
    font-weight: 700;
    font-size: 0.9rem;
    border: 1px solid rgba(0,0,0,0.1);
    transition: 0.3s;
}

.btn-secondary:hover { 
    transform: translateY(-3px);
    background: #ee89b8; 
    color: #2d3436;      
    box-shadow: 0 10px 20px rgba(162, 210, 255, 0.3); 

 }

.floating-icon {
    position: absolute;
    bottom: 10px;
    right: 20px;
    font-size: 4rem;
    opacity: 0.15;
    animation: slowFloat 6s ease-in-out infinite;
    pointer-events: none;
    color: #e06991;
}

@keyframes slowFloat {
    0% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(10deg); }
    100% { transform: translateY(0) rotate(0deg); }
}

.container { max-width: 1200px; margin: 0 auto; padding: 60px 20px; }

.grade-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
}

.grade-card {
    padding: 60px 30px;
    border-radius: 40px;
    text-decoration: none;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    display: flex; flex-direction: column; align-items: center;
    text-align: center;
    border: 1px solid rgba(255,255,255,0.1);
}

.c6 { background: var(--p-orange); } .c6:hover { background: #ffbba7; transform: translateY(-12px); }
.c7 { background: var(--p-blue); }   .c7:hover { background: #80deea; transform: translateY(-12px); }
.c8 { background: var(--p-purple); } .c8:hover { background: #b39ddb; transform: translateY(-12px); }
.c9 { background: var(--p-yellow); } .c9:hover { background: #fff59d; transform: translateY(-12px); }
.c10 { background: var(--p-green); } .c10:hover { background: #a5d6a7; transform: translateY(-12px); }
.c11 { background: var(--p-red); }   .c11:hover { background: #ef9a9a; transform: translateY(-12px); }

.grade-icon { font-size: 4.5rem; margin-bottom: 20px; transition: 0.4s; filter: drop-shadow(0 5px 10px rgba(0,0,0,0.15)); }
.grade-card:hover .grade-icon { transform: scale(1.2); }

.grade-title { font-size: 1.8rem; font-weight: 700; color: #1a1a1a; margin-bottom: 10px; }
.grade-desc { font-size: 1rem; color: #333; line-height: 1.4; font-weight: 600; }

.plan-section {
    max-width: 1100px;
    margin: 60px auto 100px;
    padding: 60px 40px;
    border-radius: 50px;
    background: linear-gradient(135deg, #fdfcfb 0%, #e2d1c3 100%);
    color: #2d3436;
}

.plan-header {
    text-align: center;
    margin-bottom: 40px;
}

.plan-header h2 {
    font-size: clamp(1.8rem, 5vw, 2.2rem);
    color: #d63031;
    margin-bottom: 15px;
    font-weight: 800;
}

.plan-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.plan-card {
    padding: 35px;
    border-radius: 35px;
    transition: transform 0.3s ease;
    position: relative;
    overflow: hidden;
    border: 2px solid rgba(255,255,255,0.5);
}

.plan-1-9 { background-color: var(--p-blue); }
.plan-10 { background-color: var(--p-green); }

.plan-card h3 {
    font-size: 1.4rem;
    margin-bottom: 20px;
    color: #2d3436;
    display: flex;
    align-items: center;
    gap: 10px;
}

.plan-card ul { list-style: none; }

.plan-card ul li {
    margin-bottom: 15px;
    line-height: 1.6;
    font-weight: 500;
    display: flex;
    gap: 10px;
}

.plan-card ul li i {
    color: #e17055;
    margin-top: 5px;
}

.price-tag {
    background: #2d3436; color: white; padding: 15px 40px; border-radius: 50px;
    display: inline-block; font-size: 1.5rem; font-weight: 800; margin-top: 30px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

.author-text { text-align: center; margin-top: 30px; font-size: 0.85rem; font-weight: 600; color: #2d3436; padding: 0 10px; }

.mid-parallax {
    height: 100vh;
    background-image: linear-gradient(rgba(255, 255, 255, 0.445), rgba(255, 255, 255, 0.5)), url(chemistry-molecule-model-periodic-table.jpg);
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    margin: 40px 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.parallax-overlay-text {
    color: #2d3436;
    padding: 20px 40px;
    font-size: 3rem;
    font-weight: 700;
    text-align: center;
}

.whatsapp-wrapper {
    position: fixed;
    bottom: 40px;
    right: 40px;
    display: flex;
    align-items: center;
    gap: 12px;
    z-index: 1000;
}

.whatsapp-text {
    background: #25d366;
    color: #fff;
    padding: 10px 14px;
    border-radius: 25px;
    font-size: 14px;
    font-weight: 500;
    box-shadow: 2px 2px 6px rgba(0,0,0,0.2);
    white-space: nowrap;
}

.whatsapp-float {
    width: 60px;
    height: 60px;
    background: #e3e7e5;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 2px 2px 6px rgba(0,0,0,0.3);
    transition: transform 0.3s;
}

.whatsapp-float:hover {
    transform: scale(1.1);
}

.whatsapp-icon {
    width: 32px;
    height: 32px;
    content: url('https://img.icons8.com/color/48/000000/whatsapp--v1.png');
}

footer {
    background: black;
    color: #f1f1f1;
    padding: 80px 8% 40px;
    border-top: 1px solid rgba(255,255,255,0.05);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.footer-col h3 { margin-bottom: 20px; font-size: 1.3rem; color: var(--primary); }
.footer-col p { color: var(--text-muted); line-height: 1.7; font-size: 0.95rem; }
.footer-links { list-style: none; margin-top: 15px; }
.footer-links li { margin-bottom: 12px; }

.footer-links a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.3s ease;
    position: relative;
    display: inline-block;
    padding-bottom: 4px;
}

.footer-links a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 1px;
    bottom: 0;
    left: 0;
    background-color: var(--primary);
    transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.footer-links a:hover {
    color: white;
}

.footer-links a:hover::after {
    width: 100%;
}

.social-row { display: flex; gap: 15px; margin-top: 25px; }
.social-row a { 
    width: 45px; height: 45px; background: rgba(255,255,255,0.05); 
    display: flex; align-items: center; justify-content: center; 
    border-radius: 15px; color: white; text-decoration: none; transition: 0.3s;
}
.social-row a:hover { background: var(--primary); transform: translateY(-5px); }

.copyright {
    text-align: center; margin-top: 50px; padding-top: 25px;
    border-top: 1px solid rgba(255,255,255,0.05); color: #636e72; font-size: 0.85rem;
    text-decoration: none;
}

.instructor-btn {
    display: inline-flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px; 
    padding: 15px 30px;
    text-decoration: none;
}

.instructor-btn i {
    margin-right: 8px; 
}

.btn-name { 
    font-weight: 700; 
}

.uni-detail::before { 
    content: " - "; 
    margin: 0 5px; 
}

@media (max-width: 768px) {
    .whatsapp-wrapper {
        display: none;
    }
    .instructor-btn {
        flex-direction: column;
        text-align: center;
        gap: 5px;
    }
    .instructor-btn i {
        margin-right: 0;
        margin-bottom: 8px;
    }
    .uni-detail::before { 
        content: ""; 
    }
    nav { padding: 12px 20px; }
    .logo { font-size: 1rem; }
    .hero { padding: 120px 20px 60px;  height: 100vh; }
    .hero h1 { font-size: 1.8rem; }
    .hero p { font-size: 0.9rem; }
    .container { padding: 40px 15px; }
    .plan-section { margin: 20px 15px; padding: 40px 20px; border-radius: 30px; }
    .grade-card { padding: 40px 20px; border-radius: 30px; }
    .grade-title { font-size: 1.4rem; }
    .grade-desc { font-size: 0.85rem; }
    footer { padding: 60px 20px 30px;  }
}

@media (max-width: 480px) {
    .hero h1 { font-size: 1.6rem; }
    .sample-card { min-width: 100%; padding: 25px; }
    .sample-title { font-size: 1.5rem; }
    .parallax-overlay-text { font-size: 1.5rem; }
    .plan-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; text-align: center; }
    .social-row { justify-content: center; }
    .price-tag { font-size: 1.2rem; padding: 10px 30px; }
}