/**
 * Navigation Styles
 * Functionality: Complete navigation styling including desktop and mobile
 * Features: Sticky header, dropdowns, mobile menu, animations
 */

/* ==========================================================================
   Navigation Base
   ========================================================================== */

nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    z-index: var(--z-fixed);
    transition: all var(--transition-base);
    will-change: transform;
}

nav.scrolled {
    background: rgba(10, 10, 10, 0.98);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.5);
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    height: var(--nav-height);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* ==========================================================================
   Logo
   ========================================================================== */

.nav-logo {
    font-size: 24px;
    font-weight: 800;
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
    transition: transform var(--transition-base);
}

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

.nav-logo:focus {
    outline: 2px solid var(--accent-blue);
    outline-offset: 4px;
    border-radius: 4px;
}

/* ==========================================================================
   Desktop Navigation Menu
   ========================================================================== */

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-2xl);
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-item {
    position: relative;
}

.nav-item > a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--text-base);
    padding: var(--spacing-sm) 0;
    transition: all var(--transition-fast);
    position: relative;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.nav-item > a:hover {
    color: var(--text-primary);
}

.nav-item > a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-blue);
    transition: width var(--transition-base);
}

.nav-item > a:hover::after,
.nav-item > a[aria-current="page"]::after {
    width: 100%;
}

.nav-item > a[aria-current="page"] {
    color: var(--text-primary);
}

/* Dropdown Icon */
.dropdown-icon {
    transition: transform var(--transition-fast);
}

.dropdown:hover .dropdown-icon,
.dropdown a[aria-expanded="true"] .dropdown-icon {
    transform: rotate(180deg);
}

/* ==========================================================================
   Dropdown Menu
   ========================================================================== */

.dropdown {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-sm) 0;
    margin-top: var(--spacing-sm);
    min-width: 220px;
    opacity: 0;
    visibility: hidden;
    transform: translateX(-50%) translateY(-10px);
    transition: all var(--transition-base);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.dropdown:hover .dropdown-menu,
.dropdown:focus-within .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.dropdown-menu::before {
    content: '';
    position: absolute;
    top: -6px;
    left: 50%;
    transform: translateX(-50%);
    width: 12px;
    height: 12px;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-left: 1px solid var(--border-color);
    transform: translateX(-50%) rotate(45deg);
}

.dropdown-item {
    padding: var(--spacing-sm) var(--spacing-lg);
    color: var(--text-secondary);
    text-decoration: none;
    display: block;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
}

.dropdown-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    width: 3px;
    background: var(--accent-blue);
    transform: translateX(-100%);
    transition: transform var(--transition-fast);
}

.dropdown-item:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    padding-left: calc(var(--spacing-lg) + 5px);
}

.dropdown-item:hover::before {
    transform: translateX(0);
}

/* ==========================================================================
   CTA Buttons
   ========================================================================== */

.nav-cta {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.cta-button-primary,
.cta-button-secondary {
    padding: 12px 24px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    font-size: var(--text-sm);
    transition: all var(--transition-base);
    white-space: nowrap;
}

.cta-button-primary {
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
    color: white;
    box-shadow: 0 5px 20px rgba(37, 99, 235, 0.3);
    position: relative;
    overflow: hidden;
}

.cta-button-primary::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 var(--transition-slow);
}

.cta-button-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(37, 99, 235, 0.5);
}

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

.cta-button-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.cta-button-secondary:hover {
    background: var(--bg-secondary);
    border-color: var(--accent-green);
    color: var(--accent-green);
}

/* ==========================================================================
   Mobile Menu Toggle
   ========================================================================== */

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    padding: var(--spacing-sm);
    cursor: pointer;
    position: relative;
    width: 48px;
    height: 48px;
    align-items: center;
    justify-content: center;
}

.hamburger {
    width: 24px;
    height: 20px;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.hamburger span {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--text-primary);
    transition: all var(--transition-base);
    transform-origin: center;
}

.mobile-menu-toggle.active .hamburger span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
}

.mobile-menu-toggle.active .hamburger span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
}

.mobile-menu-toggle.active .hamburger span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* ==========================================================================
   Mobile Navigation
   ========================================================================== */

.mobile-nav-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    z-index: var(--z-modal-backdrop);
}

.mobile-nav-overlay.active {
    opacity: 1;
    visibility: visible;
}

.mobile-nav {
    position: fixed;
    top: var(--nav-height);
    left: -100%;
    width: 100%;
    max-width: 400px;
    height: calc(100vh - var(--nav-height));
    background: var(--bg-primary);
    transition: left var(--transition-base);
    z-index: var(--z-modal);
    overflow-y: auto;
    box-shadow: 5px 0 20px rgba(0, 0, 0, 0.5);
}

.mobile-nav.active {
    left: 0;
}

.mobile-nav-header {
    padding: var(--spacing-xl);
    border-bottom: 1px solid var(--border-color);
}

.mobile-nav-logo {
    font-size: var(--text-2xl);
    font-weight: 800;
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-xs);
}

.mobile-nav-tagline {
    font-size: var(--text-sm);
    color: var(--text-secondary);
}

.mobile-nav-menu {
    list-style: none;
    padding: var(--spacing-lg);
}

.mobile-nav-item {
    border-bottom: 1px solid var(--border-color);
    opacity: 0;
    transform: translateX(-20px);
    animation: slideIn var(--transition-base) ease forwards;
    animation-delay: calc(var(--item-index) * 50ms);
}

@keyframes slideIn {
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.mobile-nav-item a {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg) 0;
    color: var(--text-primary);
    text-decoration: none;
    font-size: var(--text-lg);
    font-weight: 500;
    transition: all var(--transition-fast);
}

.mobile-nav-item a:hover {
    color: var(--accent-blue);
    padding-left: var(--spacing-sm);
}

.mobile-nav-icon {
    width: 24px;
    height: 24px;
    opacity: 0.5;
    transition: all var(--transition-fast);
}

.mobile-nav-item a:hover .mobile-nav-icon {
    opacity: 1;
    transform: translateX(5px);
}

.mobile-nav-cta {
    padding: var(--spacing-lg);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.mobile-nav-cta .cta-button-primary,
.mobile-nav-cta .cta-button-secondary {
    width: 100%;
    text-align: center;
}

/* ==========================================================================
   Responsive Design
   ========================================================================== */

@media (max-width: 1024px) {
    .nav-menu {
        display: none;
    }
    
    .nav-cta {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
}

@media (max-width: 768px) {
    :root {
        --nav-height: 60px;
    }
    
    .nav-container {
        padding: 0 var(--spacing-md);
    }
    
    .nav-logo {
        font-size: 20px;
    }
    
    .mobile-nav {
        max-width: 100%;
    }
}

/* ==========================================================================
   Accessibility
   ========================================================================== */

/* Focus styles for keyboard navigation */
.nav-item > a:focus,
.dropdown-item:focus,
.mobile-nav-item a:focus {
    outline: 2px solid var(--accent-blue);
    outline-offset: 2px;
}

/* Screen reader only text */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    nav {
        border-bottom-width: 2px;
    }
    
    .dropdown-menu {
        border-width: 2px;
    }
}