/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette - Nature-inspired with modern accents */
    --primary-green: #2d5a27;
    --accent-green: #4a9b3c;
    --light-green: #7bc142;
    --forest-dark: #1a3d16;
    --earth-brown: #8b4513;
    --sky-blue: #87ceeb;
    --white: #ffffff;
    --light-gray: #f8f9fa;
    --medium-gray: #6c757d;
    --dark-gray: #343a40;
    --gold: #ffd700;
    
    /* Typography */
    --font-primary: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-heading: 'Georgia', 'Times New Roman', serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    
    /* Shadows */
    --shadow-light: 0 2px 10px rgba(45, 90, 39, 0.1);
    --shadow-medium: 0 4px 20px rgba(45, 90, 39, 0.15);
    --shadow-heavy: 0 8px 30px rgba(45, 90, 39, 0.2);
}

body {
    font-family: var(--font-primary);
    line-height: 1.6;
    color: var(--dark-gray);
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    overflow-x: hidden;
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Header Styles */
header {
    background: linear-gradient(135deg, var(--primary-green) 0%, var(--forest-dark) 100%);
    box-shadow: var(--shadow-medium);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

header .logo {
    font-family: var(--font-heading);
    font-size: 2rem;
    font-weight: bold;
    color: var(--white);
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
    display: flex;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    position: relative;
}

header .logo::after {
    content: '🌱';
    margin-left: var(--spacing-xs);
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(-10px); }
    60% { transform: translateY(-5px); }
}

nav {
    display: flex;
    justify-content: center;
    padding-bottom: var(--spacing-sm);
}

nav ul {
    display: flex;
    list-style: none;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    justify-content: center;
}

nav a {
    color: var(--white);
    text-decoration: none;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    transition: all 0.3s ease;
    font-weight: 500;
    position: relative;
    overflow: hidden;
}

nav a::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

nav a:hover::before {
    left: 100%;
}

nav a:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--accent-green) 0%, var(--light-green) 50%, var(--sky-blue) 100%);
    padding: 8rem var(--spacing-md) var(--spacing-xl);
    text-align: center;
    position: relative;
    overflow: hidden;
    margin-top: 120px;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="80" cy="40" r="1.5" fill="rgba(255,255,255,0.1)"/><circle cx="40" cy="80" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="90" cy="90" r="2.5" fill="rgba(255,255,255,0.1)"/></svg>') repeat;
    animation: float 20s infinite linear;
    pointer-events: none;
}

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

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: bold;
    color: var(--white);
    margin-bottom: var(--spacing-md);
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
    animation: fadeInUp 1s ease-out;
}

.hero p {
    font-size: 1.2rem;
    color: var(--white);
    margin-bottom: var(--spacing-lg);
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.2);
    animation: fadeInUp 1s ease-out 0.2s both;
}

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

/* CTA Button */
.cta-button {
    display: inline-block;
    background: linear-gradient(135deg, var(--gold) 0%, #ffed4e 100%);
    color: var(--forest-dark);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-lg);
    text-decoration: none;
    font-weight: bold;
    font-size: 1.1rem;
    box-shadow: var(--shadow-medium);
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
    overflow: hidden;
    animation: fadeInUp 1s ease-out 0.4s both;
}

.cta-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transition: left 0.6s;
}

.cta-button:hover::before {
    left: 100%;
}

.cta-button:hover {
    transform: translateY(-3px) scale(1.05);
    box-shadow: var(--shadow-heavy);
}

/* Section Styles */
section {
    padding: var(--spacing-xl) 0;
    position: relative;
}

section:nth-child(even) {
    background: var(--light-gray);
}

section h2 {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    color: var(--primary-green);
    margin-bottom: var(--spacing-lg);
    text-align: center;
    position: relative;
}

section h2::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-green), var(--light-green));
    margin: var(--spacing-sm) auto;
    border-radius: 2px;
}

section h3 {
    font-size: 1.5rem;
    color: var(--forest-dark);
    margin-bottom: var(--spacing-sm);
    position: relative;
    padding-left: var(--spacing-md);
}

section h3::before {
    content: '🌿';
    position: absolute;
    left: 0;
    top: 0;
}

section h4 {
    font-size: 1.2rem;
    color: var(--accent-green);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

/* Subsection Styles */
.subsection {
    background: var(--white);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-light);
    transition: all 0.3s ease;
    border-left: 4px solid var(--accent-green);
}

.subsection:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-medium);
}

/* DAO Items */
.dao-item {
    background: linear-gradient(135deg, var(--white) 0%, #f8f9fa 100%);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-light);
    border: 2px solid transparent;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.dao-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-green), var(--light-green));
}

.dao-item:hover {
    border-color: var(--accent-green);
    transform: translateY(-3px);
    box-shadow: var(--shadow-medium);
}

/* Lists */
ul {
    list-style: none;
    padding-left: 0;
}

li {
    padding: var(--spacing-xs) 0;
    position: relative;
    padding-left: var(--spacing-md);
    transition: all 0.2s ease;
}

li::before {
    content: '🌱';
    position: absolute;
    left: 0;
    top: var(--spacing-xs);
}

li:hover {
    transform: translateX(5px);
    color: var(--accent-green);
}

/* Paragraphs */
p {
    margin-bottom: var(--spacing-sm);
    line-height: 1.7;
    text-align: justify;
}

/* Strong text */
strong {
    color: var(--primary-green);
    font-weight: 600;
}

/* HR Styling */
hr {
    border: none;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent-green), transparent);
    margin: var(--spacing-lg) 0;
}

/* Abstract Section */
#abstract {
    background: linear-gradient(135deg, var(--primary-green) 0%, var(--forest-dark) 100%);
    color: var(--white);
    padding: var(--spacing-xl) 0;
    text-align: center;
}

#abstract h2 {
    color: var(--white);
}

#abstract h2::after {
    background: linear-gradient(90deg, var(--gold), var(--light-green));
}

/* Special Academic Collaborations Section */
section h2:has-text("Academic Collaborations") {
    background: linear-gradient(135deg, var(--sky-blue), var(--accent-green));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Footer */
footer {
    background: var(--forest-dark);
    color: var(--white);
    text-align: center;
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-xl);
}

/* Responsive Design */
@media (max-width: 768px) {
    :root {
        --spacing-md: 1rem;
        --spacing-lg: 2rem;
        --spacing-xl: 3rem;
    }
    
    header .logo {
        font-size: 1.5rem;
        text-align: center;
    }
    
    nav ul {
        flex-direction: column;
        gap: var(--spacing-xs);
        align-items: center;
    }
    
    .hero {
        padding: 6rem var(--spacing-sm) var(--spacing-lg);
        margin-top: 140px;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero p {
        font-size: 1rem;
    }
    
    section h2 {
        font-size: 2rem;
    }
    
    .subsection {
        padding: var(--spacing-md);
    }
    
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    section h3 {
        font-size: 1.3rem;
    }
}

@media (max-width: 480px) {
    nav ul {
        gap: var(--spacing-xs);
    }
    
    nav a {
        padding: var(--spacing-xs);
        font-size: 0.9rem;
    }
    
    .hero {
        margin-top: 160px;
    }
    
    .cta-button {
        padding: var(--spacing-sm);
        font-size: 1rem;
    }
    
    section {
        padding: var(--spacing-lg) 0;
    }
}

/* Animation Classes */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus states for accessibility */
a:focus, button:focus {
    outline: 2px solid var(--accent-green);
    outline-offset: 2px;
}

/* Print styles */
@media print {
    header {
        position: static;
        box-shadow: none;
    }
    
    .hero {
        background: none;
        color: var(--dark-gray);
    }
    
    .hero h1, .hero p {
        color: var(--dark-gray);
    }
    
    .cta-button {
        display: none;
    }
}