/**
 * BTC University - Universal Header Styles
 * Navigation bar component that appears on all pages
 * 
 * Features:
 * - Fixed position header with glassmorphism effect
 * - Responsive navigation with mobile hamburger menu
 * - User account dropdown
 * - Active state indicators
 */

/* ============================================
   HEADER CONTAINER
============================================ */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: rgba(26, 39, 68, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(201, 184, 150, 0.1);
    z-index: var(--z-sticky);
    transition: all var(--transition-default);
}

/* Header scrolled state - darker background */
.header.scrolled {
    background: rgba(26, 39, 68, 0.98);
    box-shadow: var(--shadow-lg);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    max-width: var(--container-full);
    margin: 0 auto;
    padding: 0 var(--space-6);
}

/* ============================================
   LOGO SECTION
============================================ */

.header-logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    text-decoration: none;
    flex-shrink: 0;
}

.header-logo-img {
    height: 2.75rem;
    width: auto;
    transition: transform var(--transition-default);
}

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

.header-logo-text {
    display: flex;
    flex-direction: column;
    line-height: 1.1;
}

.header-logo-title {
    font-family: var(--font-display);
    font-size: var(--text-lg);
    font-weight: var(--font-semibold);
    color: var(--btcu-gold);
    letter-spacing: var(--tracking-wide);
}

.header-logo-subtitle {
    font-size: var(--text-xs);
    color: var(--btcu-gray-400);
    text-transform: uppercase;
    letter-spacing: var(--tracking-widest);
}

/* ============================================
   MAIN NAVIGATION
============================================ */

.header-nav {
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

.nav-link {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    font-weight: var(--font-medium);
    color: var(--btcu-gray-300);
    text-decoration: none;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    position: relative;
}

.nav-link:hover {
    color: var(--btcu-gold);
    background: rgba(201, 184, 150, 0.1);
}

.nav-link.active {
    color: var(--btcu-gold);
    background: rgba(201, 184, 150, 0.15);
}

/* Active indicator line */
.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -0.5rem;
    left: 50%;
    transform: translateX(-50%);
    width: 1.5rem;
    height: 2px;
    background: var(--btcu-gold);
    border-radius: var(--radius-full);
}

/* Nav link icons */
.nav-link-icon {
    width: 1.25rem;
    height: 1.25rem;
    opacity: 0.8;
}

.nav-link:hover .nav-link-icon {
    opacity: 1;
}

/* ============================================
   HEADER ACTIONS (Right side)
============================================ */

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

/* Search button */
.header-search-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    background: rgba(201, 184, 150, 0.1);
    border: none;
    border-radius: var(--radius-lg);
    color: var(--btcu-gray-300);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.header-search-btn:hover {
    background: rgba(201, 184, 150, 0.2);
    color: var(--btcu-gold);
}

/* Notification button */
.header-notification-btn {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    background: rgba(201, 184, 150, 0.1);
    border: none;
    border-radius: var(--radius-lg);
    color: var(--btcu-gray-300);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.header-notification-btn:hover {
    background: rgba(201, 184, 150, 0.2);
    color: var(--btcu-gold);
}

/* Notification badge */
.notification-badge {
    position: absolute;
    top: 0.25rem;
    right: 0.25rem;
    width: 0.5rem;
    height: 0.5rem;
    background: var(--btcu-orange);
    border-radius: var(--radius-full);
    border: 2px solid var(--btcu-navy);
}

/* User menu button */
.header-user-btn {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2);
    background: transparent;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.header-user-btn:hover {
    background: rgba(201, 184, 150, 0.1);
}

.header-user-avatar {
    width: 2.25rem;
    height: 2.25rem;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, var(--btcu-gold), var(--btcu-orange));
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--btcu-navy);
    font-weight: var(--font-semibold);
    font-size: var(--text-sm);
}

.header-user-info {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    line-height: 1.2;
}

.header-user-name {
    font-size: var(--text-sm);
    font-weight: var(--font-medium);
    color: var(--btcu-white);
}

.header-user-tier {
    font-size: var(--text-xs);
    color: var(--btcu-gold);
}

.header-user-chevron {
    width: 1rem;
    height: 1rem;
    color: var(--btcu-gray-400);
    transition: transform var(--transition-fast);
}

.header-user-btn[aria-expanded="true"] .header-user-chevron {
    transform: rotate(180deg);
}

/* CTA Button in header */
.header-cta {
    padding: var(--space-2) var(--space-5);
    font-size: var(--text-sm);
}

/* ============================================
   USER DROPDOWN MENU
============================================ */

.user-dropdown {
    position: absolute;
    top: calc(100% + var(--space-2));
    right: 0;
    width: 15rem;
    background: var(--btcu-white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-fast);
    z-index: var(--z-dropdown);
}

.user-dropdown.open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.user-dropdown-header {
    padding: var(--space-4);
    border-bottom: 1px solid var(--btcu-gray-200);
}

.user-dropdown-email {
    font-size: var(--text-sm);
    color: var(--btcu-gray-500);
}

.user-dropdown-menu {
    padding: var(--space-2);
}

.user-dropdown-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-3);
    font-size: var(--text-sm);
    color: var(--btcu-gray-600);
    text-decoration: none;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
}

.user-dropdown-item:hover {
    background: var(--btcu-gray-100);
    color: var(--btcu-navy);
}

.user-dropdown-item-icon {
    width: 1.25rem;
    height: 1.25rem;
    opacity: 0.7;
}

.user-dropdown-divider {
    height: 1px;
    background: var(--btcu-gray-200);
    margin: var(--space-2) 0;
}

.user-dropdown-item.logout {
    color: var(--btcu-error);
}

.user-dropdown-item.logout:hover {
    background: var(--btcu-error-light);
}

/* ============================================
   MOBILE MENU TOGGLE
============================================ */

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 2.5rem;
    height: 2.5rem;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: var(--space-2);
    gap: 5px;
}

.mobile-menu-toggle span {
    display: block;
    width: 1.5rem;
    height: 2px;
    background: var(--btcu-gold);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

/* Hamburger animation to X */
.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

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

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ============================================
   MOBILE NAVIGATION
============================================ */

.mobile-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--btcu-navy);
    padding: var(--space-6);
    opacity: 0;
    visibility: hidden;
    transform: translateX(100%);
    transition: all var(--transition-default);
    z-index: var(--z-overlay);
    overflow-y: auto;
}

.mobile-nav.open {
    opacity: 1;
    visibility: visible;
    transform: translateX(0);
}

.mobile-nav-link {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    padding: var(--space-4);
    font-size: var(--text-lg);
    font-weight: var(--font-medium);
    color: var(--btcu-gray-300);
    text-decoration: none;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    margin-bottom: var(--space-2);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
    color: var(--btcu-gold);
    background: rgba(201, 184, 150, 0.1);
}

.mobile-nav-link-icon {
    width: 1.5rem;
    height: 1.5rem;
}

.mobile-nav-divider {
    height: 1px;
    background: rgba(201, 184, 150, 0.2);
    margin: var(--space-4) 0;
}

.mobile-nav-cta {
    width: 100%;
    margin-top: var(--space-4);
}

/* ============================================
   RESPONSIVE STYLES
============================================ */

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

@media (max-width: 768px) {
    .header {
        height: var(--header-height-mobile);
    }
    
    .header-logo-text {
        display: none;
    }
    
    .header-cta {
        display: none;
    }
    
    .mobile-nav {
        top: var(--header-height-mobile);
    }
    
    main {
        padding-top: var(--header-height-mobile);
    }
}

@media (max-width: 480px) {
    .header-actions {
        gap: var(--space-2);
    }
    
    .header-search-btn,
    .header-notification-btn {
        width: 2.25rem;
        height: 2.25rem;
    }
}