/* ============================================
   ENHANCED USER EXPERIENCE CSS
   Premium UX features styling
   ============================================ */

/* ============================================
   1. READING TIME ESTIMATES
   ============================================ */

.reading-time {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: var(--font-size-xs);
    color: var(--text-tertiary);
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--bg-secondary);
    border-radius: var(--radius-full);
    border: 1px solid var(--border-light);
    font-weight: 500;
}

.reading-time i {
    font-size: 10px;
    opacity: 0.7;
}

.section-reading-time {
    margin-bottom: var(--spacing-lg);
    background: linear-gradient(135deg, 
        rgba(99, 102, 241, 0.1), 
        rgba(6, 182, 212, 0.1));
    border-color: var(--primary-color);
    color: var(--primary-color);
}

/* ============================================
   2. BREADCRUMB NAVIGATION
   ============================================ */

.breadcrumb-nav {
    position: fixed;
    top: 80px;
    left: 50%;
    transform: translateX(-50%);
    z-index: var(--z-sticky);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    pointer-events: none;
}

.breadcrumb-nav:not(.hidden) {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
}

.breadcrumb-container {
    background: var(--bg-glass);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-2xl);
    padding: var(--spacing-md) var(--spacing-lg);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    min-width: 400px;
}

.breadcrumb-items {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex: 1;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    font-size: var(--font-size-sm);
    font-weight: 500;
}

.breadcrumb-item i {
    font-size: 12px;
}

.breadcrumb-item.past {
    color: var(--text-tertiary);
    opacity: 0.6;
}

.breadcrumb-item.active {
    background: var(--primary-color);
    color: white;
    transform: scale(1.1);
}

.breadcrumb-item.future {
    color: var(--text-secondary);
    opacity: 0.4;
}

.breadcrumb-item:hover:not(.active) {
    background: var(--bg-secondary);
    transform: translateY(-2px);
}

.breadcrumb-title {
    font-size: var(--font-size-xs);
    white-space: nowrap;
}

.breadcrumb-progress {
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
    font-weight: 600;
    padding: var(--spacing-xs) var(--spacing-sm);
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-light);
}

/* ============================================
   3. KEYBOARD SHORTCUTS GUIDE
   ============================================ */

.shortcuts-modal {
    position: fixed;
    inset: 0;
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.shortcuts-modal.open {
    opacity: 1;
    visibility: visible;
}

.shortcuts-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}

.shortcuts-container {
    position: relative;
    width: 90%;
    max-width: 700px;
    max-height: 80vh;
    background: var(--bg-primary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-2xl);
    overflow: hidden;
    transform: scale(0.9) translateY(-20px);
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.shortcuts-modal.open .shortcuts-container {
    transform: scale(1) translateY(0);
}

.shortcuts-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-xl);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

.shortcuts-header h3 {
    margin: 0;
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    font-weight: 600;
}

.shortcuts-close {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    font-size: 24px;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-lg);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition-fast);
}

.shortcuts-close:hover {
    background: rgba(255, 255, 255, 0.3);
}

.shortcuts-content {
    padding: var(--spacing-xl);
    overflow-y: auto;
    max-height: 60vh;
}

.shortcuts-intro {
    margin-bottom: var(--spacing-xl);
    text-align: center;
}

.shortcuts-intro p {
    color: var(--text-secondary);
    font-size: var(--font-size-lg);
}

.shortcuts-grid {
    display: grid;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.shortcut-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    padding: var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    transition: all var(--transition-fast);
}

.shortcut-item:hover {
    background: var(--bg-tertiary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.shortcut-key {
    background: var(--bg-primary);
    color: var(--text-primary);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    font-family: var(--font-mono);
    font-weight: 600;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    min-width: 80px;
    text-align: center;
    white-space: nowrap;
}

.shortcut-description {
    color: var(--text-primary);
    font-weight: 500;
    flex: 1;
}

.shortcuts-footer {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-light);
}

.shortcuts-footer p {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
}

.shortcuts-footer kbd {
    background: var(--primary-color);
    color: white;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: var(--font-size-xs);
    font-family: var(--font-mono);
}

/* ============================================
   4. SEARCH FUNCTIONALITY
   ============================================ */

.search-modal {
    position: fixed;
    inset: 0;
    z-index: 10000;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding-top: 15vh;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.search-modal.open {
    opacity: 1;
    visibility: visible;
}

.search-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}

.search-container {
    position: relative;
    width: 90%;
    max-width: 600px;
    background: var(--bg-primary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-2xl);
    overflow: hidden;
    transform: scale(0.9) translateY(-20px);
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.search-modal.open .search-container {
    transform: scale(1) translateY(0);
}

.search-input-container {
    display: flex;
    align-items: center;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-light);
    gap: var(--spacing-md);
}

.search-icon {
    color: var(--text-tertiary);
    font-size: var(--font-size-lg);
}

#search-input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    font-size: var(--font-size-lg);
    color: var(--text-primary);
    font-family: var(--font-family);
}

#search-input::placeholder {
    color: var(--text-tertiary);
}

.search-escape {
    background: var(--bg-secondary);
    color: var(--text-secondary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: var(--font-size-xs);
    font-family: var(--font-mono);
    border: 1px solid var(--border-color);
}

.search-results {
    max-height: 400px;
    overflow-y: auto;
}

.search-empty {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-3xl);
    color: var(--text-tertiary);
    text-align: center;
}

.search-empty i {
    font-size: 48px;
    margin-bottom: var(--spacing-lg);
    opacity: 0.5;
}

.search-result-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    border-bottom: 1px solid var(--border-light);
}

.search-result-item:last-child {
    border-bottom: none;
}

.search-result-item.selected {
    background: var(--bg-secondary);
    border-left: 4px solid var(--primary-color);
}

.search-result-item:hover {
    background: var(--bg-secondary);
}

.search-result-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    color: var(--primary-color);
    flex-shrink: 0;
}

.search-result-content {
    flex: 1;
    min-width: 0;
}

.search-result-title {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    font-size: var(--font-size-base);
}

.search-result-title mark {
    background: var(--primary-color);
    color: white;
    padding: 2px 4px;
    border-radius: 3px;
    font-weight: 700;
}

.search-result-description {
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    line-height: 1.4;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.search-result-description mark {
    background: rgba(99, 102, 241, 0.2);
    color: var(--primary-color);
    padding: 1px 3px;
    border-radius: 2px;
    font-weight: 600;
}

.search-result-category {
    color: var(--text-tertiary);
    font-size: var(--font-size-xs);
    margin-top: var(--spacing-xs);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 600;
}

.search-result-type {
    color: var(--text-tertiary);
    font-size: var(--font-size-xs);
    background: var(--bg-tertiary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-full);
    text-transform: capitalize;
    font-weight: 500;
    border: 1px solid var(--border-light);
}

.search-footer {
    padding: var(--spacing-lg);
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-light);
}

.search-tips {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.search-tips span {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.search-tips kbd {
    background: var(--bg-primary);
    color: var(--text-primary);
    padding: 2px 6px;
    border-radius: 3px;
    font-size: var(--font-size-xs);
    font-family: var(--font-mono);
    border: 1px solid var(--border-color);
}

/* ============================================
   5. SEARCH HIGHLIGHT EFFECT
   ============================================ */

.search-highlight {
    animation: searchHighlight 2s ease-in-out;
    position: relative;
    z-index: 10;
}

@keyframes searchHighlight {
    0% {
        box-shadow: 0 0 0 0 rgba(99, 102, 241, 0.8);
        transform: scale(1);
    }
    50% {
        box-shadow: 0 0 0 20px rgba(99, 102, 241, 0.2);
        transform: scale(1.02);
    }
    100% {
        box-shadow: 0 0 0 0 rgba(99, 102, 241, 0);
        transform: scale(1);
    }
}

/* ============================================
   6. RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 768px) {
    .breadcrumb-container {
        min-width: 300px;
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .breadcrumb-title {
        display: none;
    }
    
    .breadcrumb-item {
        padding: var(--spacing-xs);
    }
    
    .shortcuts-container {
        width: 95%;
        max-height: 85vh;
    }
    
    .shortcuts-content {
        padding: var(--spacing-lg);
    }
    
    .shortcuts-grid {
        gap: var(--spacing-sm);
    }
    
    .shortcut-item {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
        text-align: left;
    }
    
    .shortcut-key {
        min-width: auto;
        align-self: flex-start;
    }
    
    .search-container {
        width: 95%;
    }
    
    .search-input-container {
        padding: var(--spacing-md);
    }
    
    .search-tips {
        flex-direction: column;
        gap: var(--spacing-sm);
        text-align: center;
    }
}

@media (max-width: 480px) {
    .breadcrumb-nav {
        top: 70px;
    }
    
    .breadcrumb-container {
        min-width: 250px;
        padding: var(--spacing-xs) var(--spacing-sm);
    }
    
    .reading-time {
        font-size: 10px;
        padding: 2px 6px;
    }
    
    .shortcuts-header {
        padding: var(--spacing-lg);
    }
    
    .shortcuts-content {
        padding: var(--spacing-md);
        max-height: 65vh;
    }
    
    .search-result-item {
        padding: var(--spacing-md);
    }
    
    .search-result-description {
        white-space: normal;
        overflow: visible;
        text-overflow: unset;
    }
}

/* ============================================
   7. DARK THEME ENHANCEMENTS
   ============================================ */

.dark-theme .breadcrumb-container {
    background: rgba(15, 23, 42, 0.8);
    border-color: var(--border-color);
}

.dark-theme .shortcuts-container {
    background: var(--bg-primary);
    border-color: var(--border-color);
}

.dark-theme .search-container {
    background: var(--bg-primary);
    border-color: var(--border-color);
}

.dark-theme .reading-time {
    background: var(--bg-secondary);
    border-color: var(--border-color);
}

/* ============================================
   8. ACCESSIBILITY ENHANCEMENTS
   ============================================ */

@media (prefers-reduced-motion: reduce) {
    .breadcrumb-nav,
    .shortcuts-container,
    .search-container {
        transition: none !important;
    }
    
    .search-highlight {
        animation: none !important;
        box-shadow: 0 0 0 2px var(--primary-color) !important;
    }
}

/* Focus styles for accessibility */
.breadcrumb-item:focus,
.shortcut-item:focus,
.search-result-item:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

#search-input:focus {
    outline: none;
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    .breadcrumb-container,
    .shortcuts-container,
    .search-container {
        border-width: 2px;
    }
    
    .reading-time {
        border-width: 2px;
    }
}