/* ===== CSS RESET & GLOBAL VARIABLES ===== */
:root {
    --primary-color: #0ea5e9;
    --primary-dark: #0369a1;
    --primary-light: #e0f2fe;
    --secondary-color: #8b5cf6;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --dark-color: #0f172a;
    --dark-light: #1e293b;
    --gray-900: #0f172a;
    --gray-800: #1e293b;
    --gray-700: #334155;
    --gray-600: #475569;
    --gray-500: #64748b;
    --gray-400: #94a3b8;
    --gray-300: #cbd5e1;
    --gray-200: #e2e8f0;
    --gray-100: #f1f5f9;
    --gray-50: #f8fafc;
    --white: #ffffff;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.15);
    --border-radius: 8px;
    --border-radius-lg: 16px;
    --border-radius-xl: 24px;
    --transition: all 0.3s ease;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-serif: 'Source Serif Pro', Georgia, serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    line-height: 1.6;
    color: var(--gray-700);
    background-color: var(--gray-50);
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-sans);
    font-weight: 600;
    color: var(--gray-900);
    line-height: 1.2;
}

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

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

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

ul, ol {
    list-style-position: inside;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== UTILITY CLASSES ===== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mt-5 { margin-top: 3rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }
.mb-5 { margin-bottom: 3rem; }

.p-1 { padding: 0.5rem; }
.p-2 { padding: 1rem; }
.p-3 { padding: 1.5rem; }
.p-4 { padding: 2rem; }
.p-5 { padding: 3rem; }

.d-flex { display: flex; }
.flex-column { flex-direction: column; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.align-center { align-items: center; }
.flex-wrap { flex-wrap: wrap; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }
.gap-4 { gap: 2rem; }

/* ===== BUTTONS ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.8rem 1.8rem;
    border-radius: var(--border-radius);
    font-family: var(--font-sans);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
    text-align: center;
    white-space: nowrap;
}

.btn i {
    font-size: 1.1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--white);
    box-shadow: var(--shadow-md);
}

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

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-outline:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
}

.btn-small {
    padding: 0.5rem 1.2rem;
    font-size: 0.9rem;
}

.btn-large {
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
}

.btn-block {
    width: 100%;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* ===== HEADER & NAVIGATION ===== */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--dark-color);
    color: white;
    padding: 8px;
    z-index: 9999;
    transition: top 0.3s;
}

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

.main-header {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    padding: 1rem 0;
    border-bottom: 1px solid var(--gray-200);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--gray-900);
}

.logo-icon {
    color: var(--primary-color);
    font-size: 1.8rem;
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--gray-700);
    cursor: pointer;
    padding: 0.5rem;
    z-index: 1001;
}

.main-nav {
    display: flex;
    align-items: center;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-links a {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
    color: var(--gray-600);
    padding: 0.5rem 0;
    position: relative;
}

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

.nav-links a.active {
    color: var(--primary-color);
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--primary-color);
}

/* ===== MAIN CONTENT AREA ===== */
main {
    padding-top: 80px; /* Offset for fixed header */
    min-height: 70vh;
}

/* ===== FOOTER ===== */
.main-footer {
    background-color: var(--dark-color);
    color: var(--gray-300);
    padding: 3rem 0 1.5rem;
    margin-top: auto;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-bottom: 2.5rem;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.footer-logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--white);
}

.footer-social {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.footer-social a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: var(--dark-light);
    color: var(--gray-300);
    border-radius: 50%;
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--primary-color);
    color: var(--white);
    transform: translateY(-3px);
}

.footer-links h4 {
    color: var(--white);
    font-size: 1.1rem;
    margin-bottom: 1.2rem;
    position: relative;
    padding-bottom: 0.5rem;
}

.footer-links h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background-color: var(--primary-color);
}

.footer-links ul {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.7rem;
}

.footer-links a {
    color: var(--gray-400);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.footer-links a:hover {
    color: var(--primary-color);
}

.footer-links i {
    width: 20px;
    text-align: center;
}

.footer-bottom {
    padding-top: 1.5rem;
    border-top: 1px solid var(--gray-800);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    text-align: center;
}

.copyright {
    color: var(--gray-500);
    font-size: 0.9rem;
    line-height: 1.5;
}

.footer-credits {
    color: var(--gray-500);
    font-size: 0.85rem;
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 992px) {
    .container {
        padding: 0 15px;
    }
    
    .nav-links {
        gap: 1.5rem;
    }
}

@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: block;
    }
    
    .main-nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background-color: var(--white);
        box-shadow: var(--shadow-xl);
        padding: 5rem 2rem 2rem;
        transition: right 0.3s ease;
        z-index: 1000;
    }
    
    .main-nav.active {
        right: 0;
    }
    
    .nav-links {
        flex-direction: column;
        gap: 0;
    }
    
    .nav-links li {
        width: 100%;
    }
    
    .nav-links a {
        padding: 1rem 0;
        border-bottom: 1px solid var(--gray-200);
        width: 100%;
    }
    
    .nav-links a.active::after {
        display: none;
    }
    
    .nav-links a.active {
        font-weight: 600;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 576px) {
    .logo {
        font-size: 1.4rem;
    }
    
    .logo-icon {
        font-size: 1.6rem;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .btn-outline.small {
        width: auto;
    }
}