/* Critical CSS - Above-the-fold styles for faster initial render */

/* CSS Variables - Required immediately */
:root {
    /* Theme colors */
    --background-color: #ffffff;
    --surface-color: #f8f9fa;
    --text-primary: #2c3e50;
    --text-secondary: #5a6c7d;
    --text-muted: #888888;
    --accent-color: #3498db;
    --accent-color-rgb: 52, 152, 219;
    --border-color: #e1e8ed;
    --shadow-color: rgba(0, 0, 0, 0.1);
    
    /* Button colors */
    --button-primary-bg: #3498db;
    --button-primary-hover: #2980b9;
    
    /* Hero section */
    --hero-bg: #ffffff;
    --hero-text: #2c3e50;
    
    /* Transitions */
    --transition-speed: 0.3s;
    --transition-ease: ease;
}

/* Dark theme variables */
[data-theme="dark"] {
    --background-color: #1a202c;
    --surface-color: #2d3748;
    --text-primary: #f7fafc;
    --text-secondary: #e2e8f0;
    --text-muted: #a0aec0;
    --border-color: #4a5568;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --hero-bg: #1a202c;
    --hero-text: #f7fafc;
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--background-color);
}

/* Header - Critical for navigation */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: var(--background-color);
    border-bottom: 1px solid var(--border-color);
    transition: all var(--transition-speed) var(--transition-ease);
}

.header.scrolled {
    box-shadow: 0 2px 20px var(--shadow-color);
    background-color: var(--surface-color);
}

.nav {
    padding: 0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo a {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--accent-color);
    text-decoration: none;
}

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

.nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-speed) var(--transition-ease);
}

.nav-link:hover,
.nav-link.active {
    color: var(--accent-color);
}

/* Theme toggle */
.theme-toggle {
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: 8px;
    border-radius: 4px;
    transition: all var(--transition-speed) var(--transition-ease);
}

.theme-toggle:hover {
    background-color: var(--surface-color);
}

/* Mobile menu toggle */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 3px 0;
    transition: all var(--transition-speed) var(--transition-ease);
}

/* Main content container */
.main-content {
    display: block;
}

.main {
    min-height: calc(100vh - 140px);
}

/* Hero section - Critical above-the-fold content */
.hero {
    background-color: var(--hero-bg);
    color: var(--hero-text);
    padding: 140px 0 80px;
    text-align: center;
}

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

.hero-badge {
    display: inline-block;
    background-color: var(--surface-color);
    color: var(--accent-color);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: bold;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero-highlight {
    color: var(--accent-color);
}

.hero-subtitle {
    font-size: clamp(1.1rem, 2vw, 1.3rem);
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto 2.5rem;
    line-height: 1.6;
}

.hero-features {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.hero-feature {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.hero-feature svg {
    color: var(--accent-color);
    flex-shrink: 0;
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Buttons - Critical for CTA */
.btn {
    display: inline-block;
    padding: 12px 24px;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    transition: all var(--transition-speed) var(--transition-ease);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background-color: var(--button-primary-hover);
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: transparent;
    color: var(--hero-text);
    border: 2px solid var(--hero-text);
}

.btn-secondary:hover {
    background-color: var(--hero-text);
    color: var(--hero-bg);
}

/* Mobile responsiveness for critical elements */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background-color: var(--surface-color);
        flex-direction: column;
        align-items: center; /* Center navigation items horizontally */
        padding: 2rem;
        gap: 1rem;
        margin: 0; /* Reset default ul margin */
        list-style: none; /* Remove default list styling */
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-speed) var(--transition-ease);
        box-shadow: 0 4px 20px var(--shadow-color);
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    /* Mobile navigation list items styling */
    .nav-menu li {
        list-style: none;
        width: 100%;
        max-width: 200px;
        text-align: center;
    }

    /* Mobile navigation links styling */
    .nav-menu .nav-link {
        display: block;
        text-align: center;
        padding: 12px 24px;
        width: 100%;
        border-radius: 8px;
        transition: all var(--transition-speed) var(--transition-ease);
    }

    .nav-menu .nav-link:hover,
    .nav-menu .nav-link.active {
        background-color: var(--accent-color);
        color: white;
        transform: scale(1.05);
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .hero {
        padding: 120px 0 60px;
    }

    .hero-features {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }

    .hero-actions {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 280px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .nav-container {
        padding: 0 16px;
    }

    .hero-container {
        padding: 0 16px;
    }

    .hero-badge {
        font-size: 0.8rem;
        padding: 6px 12px;
    }
}