/**
 * Phoenix Foundation Universal Navigation System
 * Consistent navigation header for all programmes:
 * - Phoenix Foundation
 * - CREP D²
 * - PCREF Challenge
 * - Learning Journey
 * 
 * NHS-level security | Executive Rolls-Royce standard
 */

:root {
    /* Brand Colors */
    --phoenix-indigo: #512DA8;
    --phoenix-lavender: #EDE7F6;
    --phoenix-slate: #4A4A4A;
    --phoenix-silver: #C0C0C0;
    --phoenix-gold: #D4AF37;
    --phoenix-white: #FFFFFF;
    
    /* Navigation Specific */
    --nav-height: 80px;
    --nav-bg: rgba(81, 45, 168, 0.98);
    --nav-border: rgba(212, 175, 55, 0.2);
    --nav-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    
    /* Transitions */
    --transition-fast: all 0.2s ease;
    --transition-normal: all 0.3s ease;
    --focus-ring: 0 0 0 3px rgba(212, 175, 55, 0.6);
}

/* Universal Navigation Header */
.phoenix-universal-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: var(--nav-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--nav-border);
    box-shadow: var(--nav-shadow);
    z-index: 1000;
    transition: var(--transition-normal);
}

.phoenix-nav-container {
    max-width: 1400px;
    height: 100%;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
}

/* Logo Section */
.phoenix-nav-logo {
    display: flex;
    align-items: center;
    gap: 1rem;
    text-decoration: none;
    transition: var(--transition-fast);
}

.phoenix-nav-logo:hover {
    transform: translateY(-2px);
}

.phoenix-logo-icon {
    width: 50px;
    height: 50px;
    background: var(--phoenix-gold);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--phoenix-indigo);
    box-shadow: 0 4px 12px rgba(212, 175, 55, 0.3);
}

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

.phoenix-logo-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--phoenix-white);
    line-height: 1.2;
}

.phoenix-logo-subtitle {
    font-size: 0.75rem;
    color: var(--phoenix-gold);
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

/* Navigation Menu */
.phoenix-nav-menu {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    list-style: none;
    margin: 0;
    padding: 0;
}

.phoenix-nav-item {
    margin: 0;
}

.phoenix-nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.2rem;
    color: var(--phoenix-lavender);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    border-radius: 10px;
    transition: var(--transition-fast);
    position: relative;
    white-space: nowrap;
}

.phoenix-nav-link:hover {
    background: rgba(212, 175, 55, 0.15);
    color: var(--phoenix-gold);
    transform: translateY(-1px);
}

.phoenix-nav-link:focus-visible {
    outline: none;
    box-shadow: var(--focus-ring);
}

.phoenix-nav-link.active {
    background: rgba(212, 175, 55, 0.25);
    color: var(--phoenix-gold);
    font-weight: 600;
}

.phoenix-nav-link.active::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 30px;
    height: 3px;
    background: var(--phoenix-gold);
    border-radius: 2px;
}

/* Mobile Menu Toggle */
.phoenix-nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 8px;
    transition: var(--transition-fast);
}

.phoenix-nav-toggle:hover {
    background: rgba(212, 175, 55, 0.15);
}

.phoenix-nav-toggle span {
    display: block;
    width: 28px;
    height: 3px;
    background: var(--phoenix-gold);
    border-radius: 2px;
    transition: var(--transition-fast);
}

.phoenix-nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translateY(10px);
}

.phoenix-nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.phoenix-nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translateY(-10px);
}

/* User Account Section */
.phoenix-nav-user {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.phoenix-user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--phoenix-gold) 0%, var(--phoenix-indigo) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--phoenix-white);
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition-fast);
    border: 2px solid var(--phoenix-gold);
}

.phoenix-user-avatar:hover {
    transform: scale(1.1);
    box-shadow: 0 0 20px rgba(212, 175, 55, 0.5);
}

/* Responsive Design - Tablet */
@media (max-width: 1024px) {
    .phoenix-nav-menu {
        gap: 0.25rem;
    }
    
    .phoenix-nav-link {
        padding: 0.5rem 0.8rem;
        font-size: 0.9rem;
    }
}

/* Responsive Design - Mobile */
@media (max-width: 768px) {
    :root {
        --nav-height: 70px;
    }
    
    .phoenix-nav-container {
        padding: 0 1rem;
    }
    
    .phoenix-nav-toggle {
        display: flex;
    }
    
    .phoenix-nav-menu {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--nav-bg);
        backdrop-filter: blur(20px);
        padding: 1.5rem;
        gap: 0.5rem;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.4s ease;
        border-bottom: 1px solid var(--nav-border);
        box-shadow: var(--nav-shadow);
    }
    
    .phoenix-nav-menu.active {
        max-height: 500px;
    }
    
    .phoenix-nav-link {
        width: 100%;
        justify-content: center;
        padding: 1rem;
        font-size: 1rem;
    }
    
    .phoenix-logo-text {
        display: none;
    }
    
    .phoenix-logo-icon {
        width: 45px;
        height: 45px;
    }
    
    .phoenix-user-avatar {
        width: 35px;
        height: 35px;
        font-size: 0.9rem;
    }
}

/* Accessibility */
.phoenix-nav-skip-link {
    position: absolute;
    top: -100px;
    left: 0;
    background: var(--phoenix-gold);
    color: var(--phoenix-indigo);
    padding: 0.75rem 1.5rem;
    text-decoration: none;
    font-weight: 600;
    border-radius: 0 0 8px 0;
    z-index: 2000;
    transition: top 0.3s ease;
}

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

/* Screen Reader Only */
.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;
}

/* Reduced Motion Support */
@media (prefers-reduced-motion: reduce) {
    * {
        animation: none !important;
        transition: none !important;
    }
}

/* Dark Mode Support (future enhancement) */
@media (prefers-color-scheme: dark) {
    :root {
        --nav-bg: rgba(26, 14, 56, 0.98);
    }
}

/* Page Body Padding to Account for Fixed Header */
body {
    padding-top: var(--nav-height);
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    .phoenix-nav-link {
        border: 1px solid currentColor;
    }
    
    .phoenix-nav-link.active {
        border-width: 2px;
    }
}