/**
 * VWCO Foundation - Main Stylesheet
 * Version: 2.0.0
 * Description: Comprehensive styles for VWCO Foundation website
 * 
 * Table of Contents:
 * 1. CSS Variables & Custom Properties
 * 2. Base Styles & Typography
 * 3. Animations & Keyframes
 * 4. Navigation Styles
 * 5. Hero Section
 * 6. Section Components
 * 7. Cards & UI Elements
 * 8. Footer Styles
 * 9. Utility Classes
 * 10. Page-Specific Styles
 * 11. Responsive Design
 * 12. Accessibility
 * 13. Print Styles
 */

/* ==========================================================================
   1. CSS Variables & Custom Properties
   ========================================================================== */
:root {
    /* Brand Colors */
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #3b82f6;
    --color-primary-50: #eff6ff;
    --color-primary-100: #dbeafe;
    
    /* Neutral Colors */
    --color-white: #ffffff;
    --color-black: #000000;
    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;
    
    /* Accent Colors */
    --color-accent-yellow: #facc15;
    --color-accent-green: #22c55e;
    --color-accent-red: #ef4444;
    
    /* Dark Theme Colors */
    --color-dark-bg: #1f1f1f;
    --color-dark-card: #2a2a2a;
    --color-dark-border: #374151;
    
    /* Typography */
    --font-family-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    --font-size-6xl: 3.75rem;
    --font-size-7xl: 4.5rem;
    
    /* Spacing */
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-10: 2.5rem;
    --spacing-12: 3rem;
    --spacing-16: 4rem;
    --spacing-20: 5rem;
    --spacing-24: 6rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;
    --radius-3xl: 1.5rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;
    --transition-smooth: 1s cubic-bezier(0.16, 1, 0.3, 1);
    
    /* Z-Index Scale */
    --z-dropdown: 10;
    --z-sticky: 20;
    --z-fixed: 30;
    --z-modal-backdrop: 40;
    --z-modal: 50;
    --z-popover: 60;
    --z-tooltip: 70;
}

/* ==========================================================================
   2. Base Styles & Typography
   ========================================================================== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family-primary);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-gray-800);
    background-color: var(--color-white);
    overflow-x: hidden;
    margin: 0;
    padding: 0;
}

/* Selection */
::selection {
    background-color: var(--color-primary-100);
    color: var(--color-primary-dark);
}

/* Headings */
h1, h2, h3, h4, h5, h6 {
    margin: 0;
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-gray-900);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

@media (min-width: 640px) {
    h1 { font-size: var(--font-size-5xl); }
    h2 { font-size: var(--font-size-4xl); }
}

/* Paragraphs & Text */
p {
    margin: 0 0 var(--spacing-4);
    color: var(--color-gray-600);
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-primary-dark);
}

/* Focus Styles for Accessibility */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Images */
img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* ==========================================================================
   3. Animations & Keyframes
   ========================================================================== */

/* Ken Burns Effect */
@keyframes kenBurns {
    0% { transform: scale(1); }
    100% { transform: scale(1.1); }
}

.animate-ken-burns {
    animation: kenBurns 20s ease-in-out infinite alternate;
}

/* Float Animation */
@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-8px); }
}

.animate-float {
    animation: float 3s ease-in-out infinite;
}

.animate-float-delayed {
    animation: float 3s ease-in-out 1.5s infinite;
}

/* Pulse Animation */
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.animate-pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Spin Animation */
@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.animate-spin {
    animation: spin 1s linear infinite;
}

/* Bounce Animation */
@keyframes bounce {
    0%, 100% {
        transform: translateY(-25%);
        animation-timing-function: cubic-bezier(0.8, 0, 1, 1);
    }
    50% {
        transform: translateY(0);
        animation-timing-function: cubic-bezier(0, 0, 0.2, 1);
    }
}

.animate-bounce {
    animation: bounce 1s infinite;
}

/* Fade In */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.animate-fade-in {
    animation: fadeIn 0.5s ease-out forwards;
}

/* Slide Up */
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-slide-up {
    animation: slideUp 0.5s ease-out forwards;
}

/* Scroll Reveal Animations */
.reveal {
    opacity: 0;
    transition: all var(--transition-smooth);
}

.reveal.active {
    opacity: 1;
    transform: translate(0, 0) !important;
}

.reveal-up { transform: translateY(40px); }
.reveal-down { transform: translateY(-40px); }
.reveal-left { transform: translateX(40px); }
.reveal-right { transform: translateX(-40px); }

/* Delay Utilities */
.delay-100 { transition-delay: 100ms; }
.delay-200 { transition-delay: 200ms; }
.delay-300 { transition-delay: 300ms; }
.delay-400 { transition-delay: 400ms; }
.delay-500 { transition-delay: 500ms; }

/* ==========================================================================
   4. Navigation Styles
   ========================================================================== */
.main-nav {
    position: sticky;
    top: 0;
    z-index: var(--z-sticky);
    background-color: var(--color-white);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
}

.main-nav.scrolled {
    box-shadow: var(--shadow-lg);
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.nav-container {
    max-width: 80rem;
    margin: 0 auto;
    padding: 0 var(--spacing-4);
    display: flex;
    justify-content: space-between;
    height: 5rem;
    transition: height var(--transition-base);
}

.main-nav.scrolled .nav-container {
    height: 4rem;
}

@media (min-width: 640px) {
    .nav-container {
        padding: 0 var(--spacing-6);
    }
}

@media (min-width: 1024px) {
    .nav-container {
        padding: 0 var(--spacing-8);
    }
}

/* Logo */
.nav-logo {
    display: flex;
    flex-shrink: 0;
    align-items: center;
    cursor: pointer;
    transition: transform var(--transition-base);
}

.nav-logo:hover {
    transform: scale(1.05);
}

.nav-logo-text {
    display: flex;
    flex-direction: column;
}

.nav-logo-title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    letter-spacing: 0.1em;
    color: var(--color-gray-800);
}

@media (min-width: 640px) {
    .nav-logo-title {
        font-size: var(--font-size-3xl);
    }
}

.nav-logo-subtitle {
    font-size: 0.625rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-gray-500);
}

/* Desktop Menu */
.nav-menu {
    display: none;
    align-items: center;
    height: 100%;
}

@media (min-width: 768px) {
    .nav-menu {
        display: flex;
    }
}

.nav-link {
    position: relative;
    display: flex;
    align-items: center;
    padding: 0 var(--spacing-5);
    height: 100%;
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-gray-600);
    transition: color var(--transition-fast);
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 3px;
    bottom: 0;
    left: 0;
    background-color: var(--color-primary);
    transition: width var(--transition-base);
}

.nav-link:hover {
    color: var(--color-primary);
}

.nav-link:hover::after {
    width: 100%;
}

.nav-link.active {
    background-color: var(--color-primary);
    color: var(--color-white);
    box-shadow: var(--shadow-md);
}

.nav-link.active:hover {
    background-color: var(--color-primary-dark);
}

.nav-link.active::after {
    display: none;
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: flex;
    align-items: center;
    padding: var(--spacing-2);
    color: var(--color-gray-600);
    background: none;
    border: none;
    cursor: pointer;
    transition: color var(--transition-fast);
}

.mobile-menu-btn:hover {
    color: var(--color-primary);
}

@media (min-width: 768px) {
    .mobile-menu-btn {
        display: none;
    }
}

/* Mobile Menu */
.mobile-menu {
    display: none;
    position: absolute;
    width: 100%;
    background-color: var(--color-white);
    border-top: 1px solid var(--color-gray-100);
    box-shadow: var(--shadow-xl);
}

.mobile-menu.open {
    display: block;
}

@media (min-width: 768px) {
    .mobile-menu {
        display: none !important;
    }
}

.mobile-menu-link {
    display: block;
    padding: var(--spacing-3) var(--spacing-4);
    font-size: var(--font-size-base);
    font-weight: 500;
    color: var(--color-gray-600);
    transition: all var(--transition-fast);
}

.mobile-menu-link:hover {
    background-color: var(--color-gray-50);
    color: var(--color-primary);
}

.mobile-menu-link.active {
    background-color: var(--color-primary-50);
    color: var(--color-primary);
    border-left: 4px solid var(--color-primary);
}

/* ==========================================================================
   5. Hero Section
   ========================================================================== */
.hero {
    position: relative;
    width: 100%;
    height: 75vh;
    min-height: 500px;
    background-color: var(--color-gray-900);
    overflow: hidden;
}

@media (min-width: 640px) {
    .hero {
        height: 70vh;
    }
}

@media (min-width: 1024px) {
    .hero {
        height: 85vh;
    }
}

.hero-background {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    opacity: 0.8;
    filter: grayscale(100%);
    mix-blend-mode: luminosity;
}

.hero-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 92%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: var(--spacing-8);
    box-shadow: 5px -5px 30px rgba(0, 0, 0, 0.15);
    border-top-right-radius: 2.5rem;
}

@media (min-width: 640px) {
    .hero-overlay {
        width: 85%;
        padding: var(--spacing-10);
    }
}

@media (min-width: 768px) {
    .hero-overlay {
        width: 75%;
    }
}

@media (min-width: 1024px) {
    .hero-overlay {
        width: 60%;
        padding: var(--spacing-12);
    }
}

.hero-title {
    font-size: 1.75rem;
    font-weight: 300;
    color: var(--color-gray-800);
    line-height: 1.3;
}

@media (min-width: 640px) {
    .hero-title {
        font-size: var(--font-size-3xl);
    }
}

@media (min-width: 1024px) {
    .hero-title {
        font-size: var(--font-size-4xl);
    }
}

@media (min-width: 1280px) {
    .hero-title {
        font-size: var(--font-size-5xl);
    }
}

.hero-title-highlight {
    color: var(--color-primary);
    font-weight: 500;
    font-style: italic;
}

/* Page Hero (for inner pages) */
.page-hero {
    position: relative;
    width: 100%;
    height: 40vh;
    min-height: 300px;
    background-color: var(--color-gray-900);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.page-hero-background {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    opacity: 0.5;
}

.page-hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: var(--spacing-4);
}

.page-hero-title {
    color: var(--color-white);
    font-size: var(--font-size-4xl);
    font-weight: 700;
    margin-bottom: var(--spacing-4);
}

@media (min-width: 640px) {
    .page-hero-title {
        font-size: var(--font-size-5xl);
    }
}

.page-hero-subtitle {
    color: var(--color-gray-300);
    font-size: var(--font-size-lg);
    max-width: 600px;
    margin: 0 auto;
}

/* Breadcrumb */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    font-size: var(--font-size-sm);
    color: var(--color-gray-400);
    margin-bottom: var(--spacing-4);
}

.breadcrumb a {
    color: var(--color-gray-400);
    transition: color var(--transition-fast);
}

.breadcrumb a:hover {
    color: var(--color-white);
}

.breadcrumb-separator {
    color: var(--color-gray-600);
}

.breadcrumb-current {
    color: var(--color-primary-light);
}

/* ==========================================================================
   6. Section Components
   ========================================================================== */
.section {
    padding: var(--spacing-16) 0;
}

@media (min-width: 640px) {
    .section {
        padding: var(--spacing-24) 0;
    }
}

.section-alt {
    background-color: var(--color-gray-50);
}

.section-dark {
    background-color: var(--color-gray-900);
    color: var(--color-white);
}

.container {
    max-width: 80rem;
    margin: 0 auto;
    padding: 0 var(--spacing-4);
}

@media (min-width: 640px) {
    .container {
        padding: 0 var(--spacing-6);
    }
}

@media (min-width: 1024px) {
    .container {
        padding: 0 var(--spacing-8);
    }
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-12);
}

.section-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-4);
}

@media (min-width: 640px) {
    .section-title {
        font-size: var(--font-size-4xl);
    }
}

.section-subtitle {
    font-size: var(--font-size-lg);
    color: var(--color-gray-500);
    max-width: 600px;
    margin: 0 auto;
}

/* Stats Section */
.stats-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-10);
    text-align: center;
}

@media (min-width: 640px) {
    .stats-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-8);
    }
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-number {
    font-size: var(--font-size-5xl);
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-4);
}

@media (min-width: 640px) {
    .stat-number {
        font-size: var(--font-size-6xl);
    }
}

@media (min-width: 1024px) {
    .stat-number {
        font-size: var(--font-size-7xl);
    }
}

.stat-divider {
    height: 4px;
    width: 100%;
    max-width: 140px;
    background-color: var(--color-primary);
    margin-bottom: var(--spacing-6);
}

.stat-label {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-gray-800);
}

@media (min-width: 640px) {
    .stat-label {
        font-size: var(--font-size-2xl);
    }
}

/* ==========================================================================
   7. Cards & UI Elements
   ========================================================================== */

/* Base Card */
.card {
    background-color: var(--color-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: all var(--transition-base);
}

.card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
}

.card-body {
    padding: var(--spacing-6);
}

/* Mission/Vision/Values Cards */
.value-card {
    background-color: var(--color-gray-50);
    padding: var(--spacing-8);
    border-top: 4px solid var(--color-primary);
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    transition: all var(--transition-base);
}

@media (min-width: 640px) {
    .value-card {
        padding: var(--spacing-10);
    }
}

.value-card:hover {
    transform: translateY(-12px);
    box-shadow: var(--shadow-2xl);
}

.value-card:hover .value-card-title {
    color: var(--color-primary);
}

.value-card-title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    text-align: center;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-8);
    transition: color var(--transition-fast);
}

@media (min-width: 640px) {
    .value-card-title {
        font-size: var(--font-size-3xl);
    }
}

.value-card-text {
    color: var(--color-gray-600);
    text-align: center;
    line-height: 1.7;
    font-size: var(--font-size-lg);
    flex-grow: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Strength Plaque */
.strength-plaque {
    position: relative;
    background-color: #e5e5e5;
    padding: var(--spacing-6);
    border: 2px solid var(--color-gray-300);
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 200px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

.strength-plaque:hover {
    background-color: var(--color-white);
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.strength-plaque:hover .strength-icon {
    transform: scale(1.25) translateY(-8px);
    color: var(--color-primary);
}

.strength-icon {
    width: 3rem;
    height: 3rem;
    color: var(--color-gray-500);
    margin-bottom: var(--spacing-4);
    transition: all var(--transition-base);
}

.strength-text {
    font-size: var(--font-size-sm);
    font-weight: 700;
    color: var(--color-gray-800);
    line-height: 1.4;
}

/* Screw decoration for plaques */
.screw {
    position: absolute;
    width: 8px;
    height: 8px;
    background-color: var(--color-gray-200);
    border: 1px solid var(--color-gray-400);
    border-radius: 50%;
}

.screw.top-left { top: 8px; left: 8px; }
.screw.top-right { top: 8px; right: 8px; }
.screw.bottom-left { bottom: 8px; left: 8px; }
.screw.bottom-right { bottom: 8px; right: 8px; }

/* Team Card */
.team-card {
    background-color: var(--color-white);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
}

.team-card:hover {
    box-shadow: var(--shadow-2xl);
    transform: translateY(-8px);
}

.team-card-image {
    width: 100%;
    height: 280px;
    object-fit: cover;
    filter: grayscale(20%);
    transition: filter var(--transition-base);
}

.team-card:hover .team-card-image {
    filter: grayscale(0%);
}

.team-card-body {
    padding: var(--spacing-6);
    text-align: center;
}

.team-card-name {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-1);
}

.team-card-role {
    font-size: var(--font-size-sm);
    color: var(--color-primary);
    font-weight: 500;
    margin-bottom: var(--spacing-3);
}

.team-card-bio {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
    line-height: 1.6;
}

/* Project Card */
.project-card {
    position: relative;
    background-color: var(--color-white);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    transition: all var(--transition-base);
}

.project-card:hover {
    box-shadow: var(--shadow-2xl);
    transform: scale(1.02);
}

.project-card-image {
    width: 100%;
    height: 220px;
    object-fit: cover;
}

.project-card-body {
    padding: var(--spacing-6);
}

.project-card-category {
    display: inline-block;
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-primary);
    background-color: var(--color-primary-50);
    padding: var(--spacing-1) var(--spacing-3);
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-3);
}

.project-card-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-3);
}

.project-card-description {
    font-size: var(--font-size-sm);
    color: var(--color-gray-600);
    line-height: 1.6;
    margin-bottom: var(--spacing-4);
}

.project-card-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-2);
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-primary);
    transition: gap var(--transition-fast);
}

.project-card-link:hover {
    gap: var(--spacing-3);
}

/* Icon Circle */
.icon-circle {
    width: 4rem;
    height: 4rem;
    border-radius: 50%;
    border: 2px solid var(--color-gray-200);
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-white);
    box-shadow: var(--shadow-sm);
}

.icon-circle svg {
    width: 2rem;
    height: 2rem;
    color: var(--color-primary-light);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-3);
    padding: var(--spacing-4) var(--spacing-8);
    font-size: var(--font-size-base);
    font-weight: 600;
    border-radius: var(--radius-full);
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
}

.btn-primary {
    background-color: var(--color-primary);
    color: var(--color-white);
    box-shadow: var(--shadow-lg);
}

.btn-primary:hover {
    background-color: var(--color-primary-dark);
    box-shadow: 0 10px 25px -5px rgba(37, 99, 235, 0.4);
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: var(--color-white);
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
}

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

.btn-lg {
    padding: var(--spacing-4) var(--spacing-12);
    font-size: var(--font-size-lg);
}

/* Partner Grid */
.partner-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1px;
    border: 1px solid var(--color-gray-200);
    background-color: var(--color-gray-200);
}

@media (min-width: 768px) {
    .partner-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

@media (min-width: 1024px) {
    .partner-grid {
        grid-template-columns: repeat(6, 1fr);
    }
}

.partner-item {
    background-color: var(--color-white);
    padding: var(--spacing-6);
    height: 7rem;
    display: flex;
    align-items: center;
    justify-content: center;
    filter: grayscale(100%);
    transition: filter var(--transition-base);
}

.partner-item:hover {
    filter: grayscale(0%);
}

/* Quote Section */
.quote-section {
    padding: var(--spacing-24) 0;
    background-color: var(--color-white);
    border-top: 1px solid var(--color-gray-100);
    border-bottom: 1px solid var(--color-gray-100);
}

.quote-container {
    max-width: 64rem;
    margin: 0 auto;
    padding: 0 var(--spacing-4);
}

@media (min-width: 640px) {
    .quote-container {
        padding: 0 var(--spacing-6);
    }
}

@media (min-width: 1024px) {
    .quote-container {
        padding: 0 var(--spacing-8);
    }
}

.quote-icon {
    width: 3rem;
    height: 3rem;
    color: var(--color-primary);
    transform: rotate(180deg);
    flex-shrink: 0;
    margin-bottom: var(--spacing-4);
}

@media (min-width: 768px) {
    .quote-icon {
        margin-bottom: 0;
        margin-right: var(--spacing-6);
    }
}

.quote-text {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-6);
    line-height: 1.4;
}

@media (min-width: 640px) {
    .quote-text {
        font-size: var(--font-size-3xl);
    }
}

@media (min-width: 1024px) {
    .quote-text {
        font-size: var(--font-size-4xl);
    }
}

.quote-description {
    font-size: var(--font-size-lg);
    color: var(--color-gray-600);
    line-height: 1.7;
}

@media (min-width: 640px) {
    .quote-description {
        font-size: var(--font-size-xl);
    }
}

/* ==========================================================================
   8. Footer Styles
   ========================================================================== */
.footer {
    background-color: var(--color-dark-bg);
    color: var(--color-gray-300);
    padding-top: 0;
    padding-bottom: var(--spacing-8);
    margin-top: var(--spacing-20);
}

/* Contact Cards */
.footer-contact-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-6);
    transform: translateY(-2.5rem);
}

@media (min-width: 768px) {
    .footer-contact-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.footer-contact-card {
    background-color: var(--color-dark-card);
    padding: var(--spacing-8);
    box-shadow: var(--shadow-lg);
    border-bottom: 4px solid var(--color-primary);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.footer-contact-icon {
    background-color: rgba(37, 99, 235, 0.1);
    padding: var(--spacing-4);
    border-radius: 50%;
    margin-bottom: var(--spacing-4);
}

.footer-contact-icon svg {
    width: 2rem;
    height: 2rem;
    color: var(--color-primary-light);
}

.footer-contact-text {
    font-size: var(--font-size-sm);
    color: var(--color-gray-400);
}

/* Footer Main Content */
.footer-main {
    padding-top: var(--spacing-4);
}

.footer-top {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding-bottom: var(--spacing-8);
    border-bottom: 1px solid var(--color-dark-border);
}

@media (min-width: 768px) {
    .footer-top {
        flex-direction: row;
        justify-content: space-between;
    }
}

.footer-logo {
    margin-bottom: var(--spacing-6);
    text-align: center;
}

@media (min-width: 768px) {
    .footer-logo {
        margin-bottom: 0;
        text-align: left;
    }
}

.footer-logo-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    letter-spacing: 0.1em;
    color: var(--color-white);
}

.footer-logo-subtitle {
    font-size: var(--font-size-xs);
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-gray-500);
}

.footer-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-6);
}

.footer-nav-link {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-gray-400);
    transition: color var(--transition-fast);
}

.footer-nav-link:hover {
    color: var(--color-primary-light);
}

/* Footer Bottom */
.footer-bottom {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding-top: var(--spacing-8);
}

@media (min-width: 768px) {
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
}

.footer-legal {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-4);
    margin-bottom: var(--spacing-6);
    width: 100%;
}

@media (min-width: 768px) {
    .footer-legal {
        justify-content: flex-start;
        gap: var(--spacing-6);
        margin-bottom: 0;
        width: auto;
    }
}

.footer-legal-link {
    font-size: var(--font-size-xs);
    color: var(--color-gray-500);
    transition: color var(--transition-fast);
}

.footer-legal-link:hover {
    color: var(--color-gray-300);
}

.footer-social {
    display: flex;
    align-items: center;
    gap: var(--spacing-4);
    width: 100%;
    justify-content: center;
}

@media (min-width: 768px) {
    .footer-social {
        gap: var(--spacing-6);
        width: auto;
        justify-content: flex-end;
    }
}

.footer-social-label {
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-gray-400);
}

.footer-social-icons {
    display: flex;
    gap: var(--spacing-3);
}

.footer-social-link {
    background-color: var(--color-gray-800);
    padding: 0.625rem;
    border-radius: 50%;
    color: var(--color-white);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color var(--transition-fast);
}

.footer-social-link:hover {
    background-color: var(--color-primary);
}

.footer-social-link svg {
    width: 1rem;
    height: 1rem;
}

.footer-copyright {
    margin-top: var(--spacing-8);
    text-align: center;
    font-size: var(--font-size-xs);
    color: var(--color-gray-600);
}

@media (min-width: 768px) {
    .footer-copyright {
        text-align: left;
    }
}

/* ==========================================================================
   9. Utility Classes
   ========================================================================== */

/* Text */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--color-primary); }
.text-white { color: var(--color-white); }
.text-gray { color: var(--color-gray-600); }
.text-dark { color: var(--color-gray-900); }

.font-light { font-weight: 300; }
.font-normal { font-weight: 400; }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }

/* Spacing */
.mt-0 { margin-top: 0; }
.mt-4 { margin-top: var(--spacing-4); }
.mt-8 { margin-top: var(--spacing-8); }
.mt-12 { margin-top: var(--spacing-12); }
.mt-16 { margin-top: var(--spacing-16); }

.mb-0 { margin-bottom: 0; }
.mb-4 { margin-bottom: var(--spacing-4); }
.mb-8 { margin-bottom: var(--spacing-8); }
.mb-12 { margin-bottom: var(--spacing-12); }
.mb-16 { margin-bottom: var(--spacing-16); }

.py-8 { padding-top: var(--spacing-8); padding-bottom: var(--spacing-8); }
.py-12 { padding-top: var(--spacing-12); padding-bottom: var(--spacing-12); }
.py-16 { padding-top: var(--spacing-16); padding-bottom: var(--spacing-16); }
.py-24 { padding-top: var(--spacing-24); padding-bottom: var(--spacing-24); }

.px-4 { padding-left: var(--spacing-4); padding-right: var(--spacing-4); }
.px-6 { padding-left: var(--spacing-6); padding-right: var(--spacing-6); }
.px-8 { padding-left: var(--spacing-8); padding-right: var(--spacing-8); }

/* Display */
.hidden { display: none; }
.block { display: block; }
.flex { display: flex; }
.grid { display: grid; }

.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }

.flex-col { flex-direction: column; }
.flex-row { flex-direction: row; }

.gap-4 { gap: var(--spacing-4); }
.gap-6 { gap: var(--spacing-6); }
.gap-8 { gap: var(--spacing-8); }

/* Width */
.w-full { width: 100%; }
.max-w-lg { max-width: 32rem; }
.max-w-xl { max-width: 36rem; }
.max-w-2xl { max-width: 42rem; }
.max-w-4xl { max-width: 56rem; }
.max-w-7xl { max-width: 80rem; }
.mx-auto { margin-left: auto; margin-right: auto; }

/* Background */
.bg-white { background-color: var(--color-white); }
.bg-gray-50 { background-color: var(--color-gray-50); }
.bg-gray-100 { background-color: var(--color-gray-100); }
.bg-primary { background-color: var(--color-primary); }

/* Border */
.border { border: 1px solid var(--color-gray-200); }
.border-t { border-top: 1px solid var(--color-gray-200); }
.border-b { border-bottom: 1px solid var(--color-gray-200); }
.rounded { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-2xl { border-radius: var(--radius-2xl); }
.rounded-full { border-radius: var(--radius-full); }

/* Shadow */
.shadow { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }
.shadow-2xl { box-shadow: var(--shadow-2xl); }

/* ==========================================================================
   10. Page-Specific Styles
   ========================================================================== */

/* About Page */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 100%;
    background-color: var(--color-primary);
}

@media (max-width: 768px) {
    .timeline::before {
        left: 20px;
    }
}

.timeline-item {
    position: relative;
    padding: var(--spacing-8) 0;
    display: flex;
    justify-content: flex-end;
}

.timeline-item:nth-child(odd) {
    justify-content: flex-start;
}

@media (max-width: 768px) {
    .timeline-item,
    .timeline-item:nth-child(odd) {
        justify-content: flex-start;
        padding-left: 50px;
    }
}

.timeline-content {
    width: 45%;
    background-color: var(--color-white);
    padding: var(--spacing-6);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    position: relative;
}

@media (max-width: 768px) {
    .timeline-content {
        width: 100%;
    }
}

.timeline-dot {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 20px;
    height: 20px;
    background-color: var(--color-primary);
    border: 4px solid var(--color-white);
    border-radius: 50%;
    z-index: 1;
}

@media (max-width: 768px) {
    .timeline-dot {
        left: 20px;
    }
}

/* Contact Page */
.contact-form {
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: var(--spacing-6);
}

.form-label {
    display: block;
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-gray-700);
    margin-bottom: var(--spacing-2);
}

.form-input,
.form-textarea {
    width: 100%;
    padding: var(--spacing-3) var(--spacing-4);
    font-size: var(--font-size-base);
    border: 2px solid var(--color-gray-200);
    border-radius: var(--radius-lg);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-textarea {
    min-height: 150px;
    resize: vertical;
}

/* Research Page */
.publication-card {
    background-color: var(--color-white);
    border-left: 4px solid var(--color-primary);
    padding: var(--spacing-6);
    margin-bottom: var(--spacing-4);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-base);
}

.publication-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateX(4px);
}

.publication-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-2);
}

.publication-meta {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
}

/* ==========================================================================
   11. Responsive Design
   ========================================================================== */
@media (max-width: 640px) {
    .hide-mobile {
        display: none !important;
    }
}

@media (min-width: 641px) and (max-width: 1023px) {
    .hide-tablet {
        display: none !important;
    }
}

@media (min-width: 1024px) {
    .hide-desktop {
        display: none !important;
    }
}

/* ==========================================================================
   12. Accessibility
   ========================================================================== */

/* Skip to main content link */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background-color: var(--color-primary);
    color: var(--color-white);
    padding: var(--spacing-2) var(--spacing-4);
    z-index: 100;
    transition: top var(--transition-fast);
}

.skip-link:focus {
    top: 0;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    
    .reveal {
        opacity: 1;
        transform: none !important;
    }
}

/* High contrast mode */
@media (prefers-contrast: high) {
    :root {
        --color-primary: #0000ff;
        --color-gray-600: #000000;
    }
}

/* ==========================================================================
   13. Print Styles
   ========================================================================== */
@media print {
    *,
    *::before,
    *::after {
        background: transparent !important;
        color: #000 !important;
        box-shadow: none !important;
        text-shadow: none !important;
    }
    
    a,
    a:visited {
        text-decoration: underline;
    }
    
    a[href]::after {
        content: " (" attr(href) ")";
    }
    
    .main-nav,
    .footer,
    .btn,
    .mobile-menu {
        display: none !important;
    }
    
    .hero {
        height: auto;
        min-height: 0;
    }
    
    .section {
        padding: 1rem 0;
    }
}