/* ===== GLOBAL RESET AND BASE STYLES ===== */

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


/* Ensure no white spaces or overflow on body and html */

html,
body {
    margin: 0;
    padding: 0;
    width: 100%;
    max-width: 100%;
    overflow-x: hidden;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
}


/* ===== HEADER AND NAVIGATION ===== */

header {
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    color: white;
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    max-width: 100%;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}


/* Navigation container with flexbox layout */

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}


/* Logo styling */

.logo {
    font-size: 1.5rem;
    font-weight: bold;
}


/* Navigation links list */

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}


/* Navigation link styling with hover effect */

.nav-links a {
    color: white;
    text-decoration: none;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: #4CAF50;
}


/* ===== HERO SECTION ===== */


/* Full-width hero section with background image */

.hero {
    background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.6)), url('https://images.unsplash.com/photo-1569163139394-de4798aa62b6?w=1920&h=1080&fit=crop');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    width: 100vw;
    max-width: 100vw;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
    margin: 0;
    padding: 0;
    margin-top: 60px;
    margin-left: 0;
    margin-right: 0;
    position: relative;
    overflow: hidden;
    left: 50%;
    right: 50%;
    margin-left: -50vw;
    margin-right: -50vw;
}


/* Wave animation overlay effect */

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="%23ffffff" fill-opacity="0.05" d="M0,96L48,112C96,128,192,160,288,186.7C384,213,480,235,576,213.3C672,192,768,128,864,128C960,128,1056,192,1152,197.3C1248,203,1344,149,1392,122.7L1440,96L1440,320L1392,320C1344,320,1248,320,1152,320C1056,320,960,320,864,320C768,320,672,320,576,320C480,320,384,320,288,320C192,320,96,320,48,320L0,320Z"></path></svg>');
    background-size: cover;
    background-position: bottom;
    animation: wave 15s ease-in-out infinite;
}


/* Floating earth emoji decoration */

.hero::after {
    content: '🌍';
    position: absolute;
    font-size: 20rem;
    opacity: 0.1;
    right: -5rem;
    bottom: -5rem;
    animation: float 6s ease-in-out infinite;
}


/* Wave animation keyframes */

@keyframes wave {
    0%,
    100% {
        transform: translateX(0);
    }
    50% {
        transform: translateX(-50px);
    }
}


/* Floating animation keyframes */

@keyframes float {
    0%,
    100% {
        transform: translateY(0) rotate(0deg);
    }
    50% {
        transform: translateY(-20px) rotate(5deg);
    }
}


/* Hero content container positioned above overlays */

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


/* Main hero heading with animation */

.hero-content h1 {
    font-size: 4rem;
    margin-bottom: 1rem;
    animation: fadeInDown 1s;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
    font-weight: 800;
    letter-spacing: 2px;
}


/* Hero description text */

.hero-content p {
    font-size: 1.4rem;
    margin-bottom: 2rem;
    animation: fadeInUp 1s;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
}


/* Call-to-action button styling */

.btn {
    display: inline-block;
    padding: 1.2rem 3rem;
    background: linear-gradient(135deg, #4CAF50 0%, #45a049 100%);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    transition: all 0.3s;
    animation: fadeIn 1.5s;
    font-weight: bold;
    font-size: 1.1rem;
    box-shadow: 0 5px 15px rgba(76, 175, 80, 0.4);
    letter-spacing: 1px;
}


/* Button hover effect */

.btn:hover {
    background: linear-gradient(135deg, #45a049 0%, #4CAF50 100%);
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(76, 175, 80, 0.5);
}


/* ===== CONTENT SECTIONS ===== */


/* General section styling with max-width container */

section {
    padding: 4rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}


/* Section headings */

h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #1e3c72;
}


/* ===== TYPES OF POLLUTION SECTION ===== */


/* Grid layout for pollution type cards */

.types-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}


/* Individual pollution type card */

.type-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}


/* Card hover effect */

.type-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}


/* Card heading */

.type-card h3 {
    color: #1e3c72;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}


/* Icon styling */

.icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}


/* ===== STATISTICS SECTION ===== */


/* Statistics section with gradient background */

.stats {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 2rem;
}


/* Statistics grid layout */

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}


/* Individual stat item */

.stat-item h3 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
}


/* ===== SOLUTIONS SECTION ===== */


/* Solutions section with light background */

.solutions {
    background: #f5f5f5;
}


/* Solutions grid layout */

.solution-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}


/* Individual solution item with accent border */

.solution-item {
    background: white;
    padding: 2rem;
    border-left: 4px solid #4CAF50;
    border-radius: 5px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
}


/* Solution item heading */

.solution-item h4 {
    color: #4CAF50;
    margin-bottom: 1rem;
    font-size: 1.3rem;
}


/* ===== CONTACT FORM SECTION ===== */


/* Contact form container */

.contact-form {
    max-width: 600px;
    margin: 0 auto;
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}


/* Form group spacing */

.form-group {
    margin-bottom: 1.5rem;
}


/* Form labels */

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: bold;
    color: #1e3c72;
}


/* Input and textarea styling */

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.8rem;
    border: 2px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
    transition: border-color 0.3s;
}


/* Input focus effect */

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #4CAF50;
}


/* Textarea specific styling */

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}


/* ===== FOOTER ===== */


/* Footer with dark background */

footer {
    background: #1e3c72;
    color: white;
    text-align: center;
    padding: 2rem;
}


/* ===== ANIMATIONS ===== */


/* Fade in from top animation */

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}


/* Fade in from bottom animation */

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}


/* Simple fade in animation */

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}


/* ===== RESPONSIVE DESIGN ===== */


/* Mobile and tablet adjustments */

@media (max-width: 768px) {
    .hero-content h1 {
        font-size: 2rem;
    }
    .nav-links {
        gap: 1rem;
    }
    h2 {
        font-size: 2rem;
    }
}