/* ========================================
   PROFESSIONAL READING EXPERIENCE ENHANCEMENTS
   ======================================== */

/* Dark Mode Variables */
:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --text-tertiary: #718096;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --primary-color: #3a86ff;
    --primary-hover: #2563eb;
    --accent-color: #ff006e;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --transition-fast: 150ms;
    --transition-base: 250ms;
    --transition-slow: 350ms;
}

/* Dark Mode Colors */
[data-theme="dark"] {
    --bg-primary: #1a202c;
    --bg-secondary: #2d3748;
    --text-primary: #f7fafc;
    --text-secondary: #e2e8f0;
    --text-tertiary: #cbd5e0;
    --border-color: #4a5568;
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
}

/* ========================================
   SMOOTH READING PROGRESS BAR
   ======================================== */
.reading-progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    transform-origin: left;
    transform: scaleX(0);
    transition: transform var(--transition-fast) ease-out;
    z-index: 9999;
    box-shadow: 0 2px 4px rgba(58, 134, 255, 0.3);
}

/* ========================================
   FLOATING ACTION BUTTONS
   ======================================== */
.fab-container {
    position: fixed;
    bottom: 32px;
    right: 32px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    z-index: 1000;
    transition: all var(--transition-base) cubic-bezier(0.4, 0, 0.2, 1);
}

.fab {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--primary-color);
    color: white;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    cursor: pointer;
    box-shadow: var(--shadow-lg);
    transition: all var(--transition-base) cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.fab::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width var(--transition-slow), height var(--transition-slow);
}

.fab:hover::before {
    width: 100%;
    height: 100%;
}

.fab:hover {
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.fab:active {
    transform: translateY(0) scale(0.95);
}

.fab.fab-secondary {
    width: 48px;
    height: 48px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.fab.fab-secondary:hover {
    background: var(--bg-primary);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

/* Tooltip for FAB */
.fab-tooltip {
    position: absolute;
    right: 68px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    padding: 8px 16px;
    border-radius: 6px;
    font-size: 14px;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transform: translateX(10px);
    transition: all var(--transition-base) ease;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.fab:hover .fab-tooltip {
    opacity: 1;
    transform: translateX(0);
}

/* Hide FAB when at top */
.fab-container.hidden {
    opacity: 0;
    transform: translateY(100px);
    pointer-events: none;
}

/* ========================================
   ENHANCED READING MODE
   ======================================== */
.reading-mode-active {
    background: var(--bg-primary);
    transition: background var(--transition-base) ease;
}

.reading-mode-active .markdown-content {
    max-width: 720px;
    margin: 0 auto;
    padding: 48px 32px;
    line-height: 1.8;
    font-size: 18px;
    color: var(--text-primary);
    letter-spacing: 0.01em;
}

.reading-mode-active .markdown-content p {
    margin-bottom: 1.5rem;
    text-align: justify;
    hyphens: auto;
}

.reading-mode-active .markdown-content h1,
.reading-mode-active .markdown-content h2,
.reading-mode-active .markdown-content h3 {
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

/* ========================================
   READING TIME ESTIMATE
   ======================================== */
.reading-meta {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 24px;
    background: var(--bg-secondary);
    border-radius: 12px;
    margin-bottom: 32px;
    border: 1px solid var(--border-color);
}

.reading-time,
.word-count {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: var(--text-secondary);
}

.reading-time i,
.word-count i {
    color: var(--primary-color);
}

/* ========================================
   THEME TOGGLE BUTTON
   ======================================== */
.theme-toggle {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-base) ease;
    position: relative;
    overflow: hidden;
}

.theme-toggle:hover {
    border-color: var(--primary-color);
    transform: rotate(180deg) scale(1.1);
}

.theme-icon {
    font-size: 20px;
    transition: all var(--transition-base) ease;
}

[data-theme="light"] .theme-icon-moon {
    display: block;
    color: var(--text-primary);
}

[data-theme="light"] .theme-icon-sun {
    display: none;
}

[data-theme="dark"] .theme-icon-sun {
    display: block;
    color: #fbbf24;
}

[data-theme="dark"] .theme-icon-moon {
    display: none;
}

/* ========================================
   ENHANCED SIDEBAR NAVIGATION
   ======================================== */
.toc-item {
    position: relative;
    padding: 12px 16px;
    border-radius: 8px;
    transition: all var(--transition-base) ease;
    cursor: pointer;
}

.toc-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 0;
    background: var(--primary-color);
    border-radius: 0 3px 3px 0;
    transition: height var(--transition-base) ease;
}

.toc-item:hover::before,
.toc-item.active::before {
    height: 70%;
}

.toc-item:hover {
    background: var(--bg-secondary);
    transform: translateX(4px);
}

.toc-item.active {
    background: rgba(58, 134, 255, 0.1);
    font-weight: 600;
    color: var(--primary-color);
}

/* ========================================
   SMOOTH SCROLL BEHAVIOR
   ======================================== */
html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

/* Override scroll behavior for reduced motion */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
    
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* ========================================
   ENHANCED SEARCH EXPERIENCE
   ======================================== */
.search-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 2000;
    display: none;
    align-items: flex-start;
    justify-content: center;
    padding-top: 10vh;
    animation: fadeIn 200ms ease;
}

.search-overlay.active {
    display: flex;
}

.search-modal {
    background: var(--bg-primary);
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    width: 90%;
    max-width: 640px;
    max-height: 70vh;
    overflow: hidden;
    animation: slideDown 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.search-modal-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
}

.search-input-wrapper {
    position: relative;
}

.search-modal-input {
    width: 100%;
    padding: 12px 48px 12px 48px;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 16px;
    transition: all var(--transition-base) ease;
    background: var(--bg-primary);
    color: var(--text-primary);
}

.search-modal-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(58, 134, 255, 0.1);
}

.search-icon {
    position: absolute;
    left: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-tertiary);
}

.search-close {
    position: absolute;
    right: 16px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-tertiary);
    cursor: pointer;
    padding: 4px;
    border-radius: 4px;
    transition: all var(--transition-base) ease;
}

.search-close:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.search-results-container {
    max-height: 400px;
    overflow-y: auto;
    padding: 8px;
}

.search-result-item {
    padding: 16px;
    border-radius: 8px;
    cursor: pointer;
    transition: all var(--transition-base) ease;
    border: 1px solid transparent;
}

.search-result-item:hover {
    background: var(--bg-secondary);
    border-color: var(--primary-color);
    transform: translateX(4px);
}

.search-result-title {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.search-result-excerpt {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.5;
}

.search-highlight {
    background: rgba(255, 235, 59, 0.3);
    color: var(--text-primary);
    font-weight: 600;
    padding: 2px 4px;
    border-radius: 2px;
}

/* ========================================
   ENHANCED TYPOGRAPHY
   ======================================== */
.markdown-content {
    font-feature-settings: "kern" 1, "liga" 1, "calt" 1;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.markdown-content::selection {
    background: rgba(58, 134, 255, 0.2);
    color: var(--text-primary);
}

/* Drop cap for first paragraph */
.markdown-content.reading-mode-active > p:first-of-type::first-letter {
    font-size: 3.5em;
    font-weight: 700;
    line-height: 1;
    float: left;
    margin: 0 8px 0 0;
    color: var(--primary-color);
}

/* ========================================
   ENHANCED CODE BLOCKS
   ======================================== */
/* Don't override pre background - let Highlight.js handle it completely */
.markdown-content pre {
    position: relative;
    border-radius: 12px !important;
    padding: 20px !important;
    overflow-x: auto;
    /* Highlight.js styles will apply here - both light and dark themes */
}

/* Don't override code text colors - Highlight.js handles everything */
.markdown-content pre code {
    font-family: 'SF Mono', 'Monaco', 'Cascadia Code', 'Roboto Mono', 'Consolas', monospace !important;
    font-size: 14px !important;
    line-height: 1.6 !important;
    background-color: transparent !important;
    /* Highlight.js will handle all color and background styling */
}

/* Code copy button */
.code-block-wrapper {
    position: relative;
}

.code-copy-btn {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 6px 12px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 12px;
    cursor: pointer;
    opacity: 0;
    transition: all var(--transition-base) ease;
}

.code-block-wrapper:hover .code-copy-btn {
    opacity: 1;
}

.code-copy-btn:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* ========================================
   MOBILE OPTIMIZATIONS
   ======================================== */
@media (max-width: 768px) {
    .fab-container {
        bottom: 20px;
        right: 20px;
        gap: 8px;
    }
    
    .fab {
        width: 48px;
        height: 48px;
        font-size: 18px;
    }
    
    .fab.fab-secondary {
        width: 42px;
        height: 42px;
    }
    
    .fab-tooltip {
        display: none;
    }
    
    .reading-mode-active .markdown-content {
        padding: 24px 16px;
        font-size: 16px;
    }
    
    .reading-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
        padding: 12px 16px;
    }
    
    .search-modal {
        width: 95%;
        max-height: 80vh;
    }
}

/* ========================================
   PRINT STYLES
   ======================================== */
@media print {
    .fab-container,
    .reading-progress-bar,
    .theme-toggle,
    .search-overlay {
        display: none !important;
    }
    
    .markdown-content {
        max-width: none !important;
        padding: 0 !important;
    }
}

/* ========================================
   ACCESSIBILITY ENHANCEMENTS
   ======================================== */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Focus styles */
*:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Skip to content link */
.skip-to-content {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary-color);
    color: white;
    padding: 8px 16px;
    text-decoration: none;
    border-radius: 0 0 8px 0;
    transition: top var(--transition-base) ease;
    z-index: 10000;
}

.skip-to-content:focus {
    top: 0;
}

/* ========================================
   LOADING STATES
   ======================================== */
.skeleton-loader {
    background: linear-gradient(
        90deg,
        var(--bg-secondary) 0%,
        var(--bg-primary) 50%,
        var(--bg-secondary) 100%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s ease-in-out infinite;
    border-radius: 8px;
}

@keyframes shimmer {
    0% {
        background-position: -200% 0;
    }
    100% {
        background-position: 200% 0;
    }
}

.content-loading {
    opacity: 0.5;
    pointer-events: none;
    user-select: none;
}

/* ========================================
   TOOLTIP COMPONENT
   ======================================== */
.tooltip {
    position: relative;
    display: inline-block;
}

.tooltip .tooltiptext {
    visibility: hidden;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    text-align: center;
    border-radius: 6px;
    padding: 8px 12px;
    position: absolute;
    z-index: 1000;
    bottom: 125%;
    left: 50%;
    transform: translateX(-50%);
    opacity: 0;
    transition: opacity var(--transition-base) ease;
    font-size: 12px;
    white-space: nowrap;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.tooltip .tooltiptext::after {
    content: "";
    position: absolute;
    top: 100%;
    left: 50%;
    margin-left: -5px;
    border-width: 5px;
    border-style: solid;
    border-color: var(--bg-secondary) transparent transparent transparent;
}

.tooltip:hover .tooltiptext {
    visibility: visible;
    opacity: 1;
}