/* ===================================
   ELLUME DESIGN SYSTEM - GLOBAL STYLES
   =================================== */

/* CSS Custom Properties */
:root {
    /* Primary Colors */
    --color-primary-blue: #0066CC;
    --color-accent-cyan: #00B4D8;
    --color-accent-green: #00CC66;
    
    /* Neutrals */
    --color-dark: #0b1120;
    --color-dark-alt: #1a1a1a;
    --color-gray-900: #111827;
    --color-gray-800: #1f2937;
    --color-gray-700: #374151;
    --color-gray-500: #6b7280;
    --color-gray-300: #d1d5db;
    --color-light-gray: #f5f5f5;
    --color-white: #ffffff;
    
    /* Solar Theme Colors */
    --color-solar-light: #CAF0F8;
    --color-solar-blue: #023E8A;
    --color-solar-accent: #fbbf24;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;
    
    /* Typography */
    --font-family: 'Inter', sans-serif;
    --font-weight-light: 300;
    --font-weight-normal: 400;
    --font-weight-semibold: 600;
    --font-weight-bold: 800;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    --transition-very-slow: 0.7s ease;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
    --shadow-glow-cyan: 0 0 15px rgba(0, 180, 216, 0.3);
    --shadow-glow-blue: 0 0 15px rgba(0, 102, 204, 0.3);
}

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

body {
    font-family: var(--font-family);
    line-height: 1.6;
    color: var(--color-gray-900);
    overflow-x: hidden;
}

/* Split Screen Hero Animation */
.split-section {
    transition: all var(--transition-slow) ease-in-out;
    position: relative;
    overflow: hidden;
}

.split-container:hover .split-section {
    width: 45%;
    filter: grayscale(80%);
}

.split-container .split-section:hover {
    width: 55%;
    filter: grayscale(0%);
    z-index: 10;
}

/* Overlay Gradients */
.overlay-gradient {
    background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
}

.overlay-dark {
    background: linear-gradient(to bottom, rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.3));
}

/* Tech Grid Pattern */
.tech-grid {
    background-size: 40px 40px;
    background-image:
        linear-gradient(to right, rgba(0, 255, 255, 0.1) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(0, 255, 255, 0.1) 1px, transparent 1px);
}

/* Scroll Animations */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

.slide-in-left {
    opacity: 0;
    transform: translateX(-50px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.slide-in-left.visible {
    opacity: 1;
    transform: translateX(0);
}

.slide-in-right {
    opacity: 0;
    transform: translateX(50px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.slide-in-right.visible {
    opacity: 1;
    transform: translateX(0);
}

/* Card Styles */
.card {
    background: var(--color-white);
    border-radius: 0.5rem;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.card-dark {
    background: var(--color-gray-800);
    color: var(--color-white);
}

/* Button Styles */
.btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    font-weight: var(--font-weight-bold);
    text-decoration: none;
    text-align: center;
    border: none;
    cursor: pointer;
    transition: all var(--transition-normal);
    border-radius: 0;
}

.btn-primary {
    background: var(--color-primary-blue);
    color: var(--color-white);
}

.btn-primary:hover {
    background: var(--color-accent-cyan);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-outline-cyan {
    background: transparent;
    border: 2px solid var(--color-accent-cyan);
    color: var(--color-accent-cyan);
}

.btn-outline-cyan:hover {
    background: var(--color-accent-cyan);
    color: var(--color-dark);
    box-shadow: var(--shadow-glow-cyan);
}

.btn-white {
    background: var(--color-white);
    color: var(--color-solar-blue);
}

.btn-white:hover {
    background: var(--color-solar-accent);
    color: var(--color-dark);
}

/* Section Styles */
.section {
    padding: var(--spacing-3xl) var(--spacing-lg);
}

.section-dark {
    background: var(--color-dark);
    color: var(--color-white);
}

.section-light {
    background: var(--color-light-gray);
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* Typography Utilities */
.text-gradient-cyan {
    background: linear-gradient(135deg, var(--color-accent-cyan), var(--color-primary-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.text-shadow-cyan {
    text-shadow: 0 0 15px rgba(0, 180, 216, 0.5);
}

/* Grid Layouts */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
}

/* Image Hover Effects */
.img-hover-zoom {
    overflow: hidden;
}

.img-hover-zoom img {
    transition: transform var(--transition-very-slow);
}

.img-hover-zoom:hover img {
    transform: scale(1.1);
}

/* Project Portfolio Filter */
.filter-btn {
    padding: 0.5rem 1.5rem;
    background: transparent;
    border: 2px solid var(--color-gray-300);
    color: var(--color-gray-700);
    font-weight: var(--font-weight-semibold);
    cursor: pointer;
    transition: all var(--transition-fast);
    margin: 0.25rem;
}

.filter-btn:hover,
.filter-btn.active {
    background: var(--color-primary-blue);
    border-color: var(--color-primary-blue);
    color: var(--color-white);
}

/* Mobile Menu */
.mobile-menu {
    display: none;
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 300px;
    height: 100vh;
    background: var(--color-dark);
    z-index: 100;
    transition: right var(--transition-normal);
    padding: var(--spacing-xl) var(--spacing-lg);
}

.mobile-menu.active {
    right: 0;
    display: block;
}

.mobile-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(0, 0, 0, 0.7);
    z-index: 99;
}

.mobile-overlay.active {
    display: block;
}

/* Responsive Utilities */
@media (max-width: 768px) {
    .section {
        padding: var(--spacing-xl) var(--spacing-md);
    }
    
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
    
    .split-container {
        flex-direction: column;
    }
    
    .split-section {
        width: 100% !important;
        height: 50vh;
    }
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: var(--color-white);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Form Styles */
.form-input,
.form-textarea,
.form-select {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--color-gray-300);
    background: var(--color-white);
    font-family: var(--font-family);
    font-size: 1rem;
    transition: border-color var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
    outline: none;
    border-color: var(--color-primary-blue);
}

.form-input.error,
.form-textarea.error {
    border-color: #ef4444;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: var(--font-weight-semibold);
    color: var(--color-gray-700);
}

/* Success Message */
.message-success {
    padding: 1rem;
    background: #10b981;
    color: var(--color-white);
    border-radius: 0.25rem;
    margin: 1rem 0;
}

.message-error {
    padding: 1rem;
    background: #ef4444;
    color: var(--color-white);
    border-radius: 0.25rem;
    margin: 1rem 0;
}

/* SDG Badge Styles */
.sdg-badge {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--color-white);
    border-left: 4px solid var(--color-accent-green);
    box-shadow: var(--shadow-sm);
    margin-bottom: var(--spacing-md);
}

.sdg-badge:hover {
    box-shadow: var(--shadow-md);
    transform: translateX(5px);
    transition: all var(--transition-normal);
}