/* ==========================================================================
   CSS Custom Properties (Theme Variables)
   ========================================================================== */

:root {
    /* Light Mode (Default) - Colorful Theme */
    --bg-primary: #ede9fe;
    --bg-secondary: #f3f0ff;
    --bg-sidebar: linear-gradient(180deg, #e0dbff 0%, #f0e0ff 100%);
    --bg-sidebar-solid: #e0dbff;
    --text-primary: #2d3748;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --highlight-bg: #ffd43b;
    --highlight-text: #1a202c;
    --border-color: #c7d2fe;
    --shadow-color: rgba(99, 102, 241, 0.15);
    --overlay-color: rgba(49, 46, 129, 0.5);
    --btn-bg: #e0e7ff;
    --btn-hover: #c7d2fe;
    --btn-active: #a5b4fc;
    --focus-ring: #6366f1;
    --error-bg: #fee2e2;
    --error-text: #dc2626;
    --error-border: #fca5a5;
    
    /* Accent colors for light theme */
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #d946ef 100%);
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    
    /* Typography */
    --font-family: 'Noto Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-base: 18px;
    --font-size-sm: 14px;
    --font-size-lg: 20px;
    --font-size-xl: 24px;
    --line-height: 1.6;
    
    /* Layout */
    --sidebar-width: 280px;
    --max-content-width: 700px;
    --top-bar-height: 60px;
    --controls-height: 80px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
}

/* Dark Mode */
[data-theme="dark"] {
    --bg-primary: #1e1e1e;
    --bg-secondary: #2a2a2a;
    --bg-sidebar: #252525;
    --bg-sidebar-solid: #252525;
    --text-primary: #e0e0e0;
    --text-secondary: #b0b0b0;
    --text-muted: #808080;
    --highlight-bg: #b8860b;
    --highlight-text: #1e1e1e;
    --border-color: #404040;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --overlay-color: rgba(0, 0, 0, 0.7);
    --btn-bg: #3a3a3a;
    --btn-hover: #4a4a4a;
    --btn-active: #5a5a5a;
    --error-bg: #450a0a;
    --error-text: #fca5a5;
    --error-border: #7f1d1d;
    --accent-primary: #818cf8;
    --accent-secondary: #a78bfa;
    --accent-gradient: linear-gradient(135deg, #818cf8 0%, #a78bfa 50%, #e879f9 100%);
}

/* ==========================================================================
   Base Styles & Reset
   ========================================================================== */

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
    height: 100%;
}

body {
    font-family: var(--font-family);
    font-size: 1rem;
    line-height: var(--line-height);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    height: 100vh;
    height: 100dvh;
    overflow: hidden;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Focus Styles for Accessibility */
:focus {
    outline: 2px solid var(--focus-ring);
    outline-offset: 2px;
}

:focus:not(:focus-visible) {
    outline: none;
}

:focus-visible {
    outline: 2px solid var(--focus-ring);
    outline-offset: 2px;
}

/* ==========================================================================
   Sidebar / Navigation Menu
   ========================================================================== */

.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    z-index: 100;
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-normal), background-color var(--transition-normal);
}

/* Mobile: Hidden by default */
@media (max-width: 767px) {
    .sidebar {
        transform: translateX(-100%);
        box-shadow: 2px 0 10px var(--shadow-color);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
}

/* Desktop: Always visible */
@media (min-width: 768px) {
    .sidebar {
        transform: translateX(0);
    }
}

.sidebar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
}

.sidebar-header h2 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
}

.close-menu-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: none;
    border: none;
    border-radius: 8px;
    color: var(--text-primary);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.close-menu-btn:hover {
    background-color: var(--btn-bg);
}

/* Desktop: Hide close button */
@media (min-width: 768px) {
    .close-menu-btn {
        display: none;
    }
}

/* Sidebar Actions (Paste Button) */
.sidebar-actions {
    padding: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.paste-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    background: none;
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    font-size: var(--font-size-sm);
    font-family: inherit;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.paste-btn:hover {
    background-color: var(--btn-bg);
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}

.paste-btn:active {
    background-color: var(--btn-hover);
}

.paste-btn svg {
    flex-shrink: 0;
}

/* Pasted text title styling - non-interactive */
.text-title.pasted-text {
    font-style: italic;
    color: var(--text-secondary);
    cursor: default;
}

.text-title.pasted-text:hover {
    background-color: transparent;
}

.text-title.pasted-text::before {
    content: '';
}

.text-list {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-md);
}

.text-item {
    display: block;
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
    background: none;
    border: none;
    border-radius: 8px;
    text-align: left;
    font-size: 1rem;
    font-family: inherit;
    color: var(--text-primary);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.text-item:hover {
    background-color: var(--btn-bg);
}

.text-item.active {
    background: var(--accent-gradient);
    color: white;
    font-weight: 500;
    box-shadow: 0 2px 8px var(--shadow-color);
}

/* Menu Overlay (Mobile) */
.menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--overlay-color);
    z-index: 90;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.menu-overlay.visible {
    opacity: 1;
    visibility: visible;
}

@media (min-width: 768px) {
    .menu-overlay {
        display: none;
    }
}

/* ==========================================================================
   Main Content Area
   ========================================================================== */

.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    transition: margin-left var(--transition-normal);
    min-height: 0;
    overflow: hidden;
}

/* Desktop: Offset for sidebar */
@media (min-width: 768px) {
    .main-content {
        margin-left: var(--sidebar-width);
    }
}

/* Top Bar / Header */
.top-bar {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    height: var(--top-bar-height);
    padding: 0 var(--spacing-lg);
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    z-index: 50;
    transition: background-color var(--transition-normal);
    flex-shrink: 0;
}

.hamburger-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: none;
    border: none;
    border-radius: 8px;
    color: var(--text-primary);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.hamburger-btn:hover {
    background-color: var(--btn-bg);
}

/* Hide hamburger on desktop */
@media (min-width: 768px) {
    .hamburger-btn {
        display: none;
    }
}

.app-title {
    flex: 1;
    font-size: var(--font-size-lg);
    font-weight: 600;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Theme Toggle Button */
.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: none;
    border: none;
    border-radius: 8px;
    color: var(--text-primary);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.theme-toggle:hover {
    background-color: var(--btn-bg);
}

/* Show/hide sun/moon icons based on theme */
.sun-icon {
    display: block;
}

.moon-icon {
    display: none;
}

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

[data-theme="dark"] .moon-icon {
    display: block;
}

/* ==========================================================================
   Reading Area
   ========================================================================== */

.reading-area {
    flex: 1;
    max-width: var(--max-content-width);
    width: 100%;
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-lg);
    overflow-y: auto;
    min-height: 0;
}

.text-title {
    font-size: var(--font-size-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 3px solid;
    border-image: var(--accent-gradient) 1;
    cursor: pointer;
    transition: background-color var(--transition-fast), color var(--transition-fast);
    border-radius: 3px;
}

.text-title:hover {
    background-color: var(--btn-hover);
}

.text-title.highlight {
    background: var(--accent-gradient);
    color: white;
    border-radius: 6px;
    padding: var(--spacing-xs) var(--spacing-sm);
    margin-left: calc(-1 * var(--spacing-sm));
}

.text-content {
    font-size: 1rem;
    line-height: var(--line-height);
    color: var(--text-primary);
}

.placeholder-text {
    color: var(--text-muted);
    font-style: italic;
    text-align: center;
    padding: var(--spacing-xl);
}

/* Segment Spans */
.segment {
    display: inline;
    padding: 2px 0;
    border-radius: 3px;
    transition: background-color var(--transition-fast), color var(--transition-fast);
    cursor: pointer;
}

.segment:hover {
    background-color: var(--btn-hover);
}

.segment.highlight {
    background: var(--accent-gradient);
    color: white;
    padding: 2px 4px;
    border-radius: 4px;
    box-shadow: 0 2px 8px var(--shadow-color);
}

/* Preserve whitespace and line breaks */
.text-content {
    white-space: pre-wrap;
    word-wrap: break-word;
}

/* ==========================================================================
   Playback Controls
   ========================================================================== */

.playback-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-lg);
    height: var(--controls-height);
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    transition: background-color var(--transition-normal);
    flex-shrink: 0;
}

.control-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background-color: var(--btn-bg);
    border: none;
    border-radius: 50%;
    color: var(--text-primary);
    cursor: pointer;
    transition: background-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.control-btn.play-btn {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 15px var(--shadow-color);
}

.control-btn.play-btn:hover:not(:disabled) {
    transform: scale(1.08);
    box-shadow: 0 6px 20px var(--shadow-color);
}

.control-btn:hover:not(:disabled) {
    background-color: var(--btn-hover);
    transform: scale(1.05);
}

.control-btn:active:not(:disabled) {
    background-color: var(--btn-active);
    transform: scale(0.95);
}

.control-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Play/Pause Button States */
.play-btn .pause-icon {
    display: none;
}

.play-btn.playing .play-icon {
    display: none;
}

.play-btn.playing .pause-icon {
    display: block;
}

/* ==========================================================================
   Loading Indicator
   ========================================================================== */

.loading-indicator {
    position: absolute;
    left: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    animation: fadeIn var(--transition-fast) ease;
}

.loading-indicator[hidden] {
    display: none;
}

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

.loading-spinner {
    width: 16px;
    height: 16px;
    border: 2px solid var(--border-color);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading-text {
    color: var(--text-muted);
}

/* Segment loading state - pulsing highlight */
.segment.loading {
    background: var(--btn-bg);
    animation: segmentPulse 1s ease-in-out infinite;
}

.text-title.loading {
    animation: segmentPulse 1s ease-in-out infinite;
}

@keyframes segmentPulse {
    0%, 100% {
        opacity: 1;
        background-color: var(--btn-bg);
    }
    50% {
        opacity: 0.6;
        background-color: var(--btn-hover);
    }
}

/* Playback controls needs relative positioning for loading indicator */
.playback-controls {
    position: relative;
}

/* ==========================================================================
   Error Banner
   ========================================================================== */

.error-banner {
    position: fixed;
    bottom: calc(var(--controls-height) + var(--spacing-md));
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    background-color: var(--error-bg);
    border: 1px solid var(--error-border);
    border-radius: 8px;
    color: var(--error-text);
    font-size: var(--font-size-sm);
    max-width: calc(100% - var(--spacing-xl) * 2);
    z-index: 60;
    animation: slideUp var(--transition-normal) ease;
}

.error-banner[hidden] {
    display: none;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateX(-50%) translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
}

/* Desktop: Offset for sidebar */
@media (min-width: 768px) {
    .error-banner {
        left: calc(50% + var(--sidebar-width) / 2);
    }
}

.retry-btn {
    padding: var(--spacing-xs) var(--spacing-md);
    background-color: var(--error-text);
    border: none;
    border-radius: 4px;
    color: white;
    font-size: var(--font-size-sm);
    font-weight: 500;
    cursor: pointer;
    transition: opacity var(--transition-fast);
}

.retry-btn:hover {
    opacity: 0.9;
}

.dismiss-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background: none;
    border: none;
    border-radius: 4px;
    color: var(--error-text);
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.dismiss-btn:hover {
    background-color: var(--error-border);
}

/* ==========================================================================
   Speaker Select Dropdown
   ========================================================================== */

.speaker-select {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--btn-bg);
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
    min-width: 80px;
}

.speaker-select:hover {
    background-color: var(--btn-hover);
    border-color: var(--accent-primary);
}

.speaker-select:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

/* Dark mode select styling */
[data-theme="dark"] .speaker-select {
    background-color: var(--btn-bg);
    color: var(--text-primary);
    border-color: var(--border-color);
}

[data-theme="dark"] .speaker-select option {
    background-color: var(--bg-secondary);
    color: var(--text-primary);
}

/* ==========================================================================
   Toast Message Box
   ========================================================================== */

.custom-message-box {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--accent-gradient);
    color: white;
    padding: 15px 25px;
    border-radius: 12px;
    z-index: 1000;
    text-align: center;
    box-shadow: 0 8px 32px var(--shadow-color);
    font-size: 1.1em;
    font-weight: 500;
    max-width: 90%;
    word-wrap: break-word;
    animation: toastFadeIn 0.3s ease, toastFadeOut 0.3s ease 3.7s forwards;
}

@keyframes toastFadeIn {
    from {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.9);
    }
    to {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

@keyframes toastFadeOut {
    from {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
    to {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.9);
    }
}

/* Dark mode toast */
[data-theme="dark"] .custom-message-box {
    background: linear-gradient(135deg, #4338ca 0%, #6d28d9 50%, #a855f7 100%);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

/* ==========================================================================
   Cyrillic-to-Latin Conversion Animation
   ========================================================================== */

/* Container state during conversion */
.text-content.converting {
    pointer-events: none;
    position: relative;
}

.text-content.converting::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--accent-gradient);
    border-radius: 2px;
    animation: conversionProgress 2s ease-in-out infinite;
}

@keyframes conversionProgress {
    0% {
        transform: scaleX(0);
        transform-origin: left;
    }
    50% {
        transform: scaleX(1);
        transform-origin: left;
    }
    51% {
        transform: scaleX(1);
        transform-origin: right;
    }
    100% {
        transform: scaleX(0);
        transform-origin: right;
    }
}

/* Word spans during conversion */
.converting-word {
    display: inline;
    transition: opacity 40ms ease, transform 40ms ease, color 40ms ease;
}

/* Word fade-out animation (Cyrillic disappearing) */
.converting-word.word-fade-out {
    opacity: 0;
    transform: translateY(-2px);
    color: var(--accent-primary);
}

/* Word fade-in animation (Latin appearing) */
.converting-word.word-fade-in {
    animation: wordFadeIn 80ms ease forwards;
    color: var(--accent-secondary);
}

@keyframes wordFadeIn {
    from {
        opacity: 0;
        transform: translateY(2px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Converted word styling */
.converting-word.word-converted {
    color: var(--text-primary);
}

/* Subtle pulse on text content during conversion to indicate activity */
.text-content.converting {
    animation: subtlePulse 1.5s ease-in-out infinite;
}

@keyframes subtlePulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.85;
    }
}

/* ==========================================================================
   Utility Classes
   ========================================================================== */

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

/* ==========================================================================
   Scrollbar Styling
   ========================================================================== */

::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

/* ==========================================================================
   App Container, Header & Footer (similar to keyboard_pro)
   ========================================================================== */

.app-container {
    display: flex;
    flex-direction: column;
    height: 100%;
    overflow: hidden;
}

.app-header {
    flex-shrink: 0;
    padding: var(--spacing-sm);
    background: var(--accent-gradient);
}

/* Desktop: Offset header for sidebar */
@media (min-width: 768px) {
    .app-header {
        margin-left: var(--sidebar-width);
    }
}

.app-header-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    max-width: var(--max-content-width);
    margin: 0 auto;
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 2px 10px var(--shadow-color);
    border-radius: 8px;
    padding: 0.5rem 1rem;
}

[data-theme="dark"] .app-header-content {
    background: rgba(30, 30, 30, 0.95);
}

.app-logo {
    height: 36px;
    width: auto;
    border-radius: 4px;
    transition: transform 0.2s ease;
    flex-shrink: 0;
}

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

.app-header-text {
    text-align: left;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.app-header-text h1 {
    margin: 0;
    font-size: 1.3rem;
    color: var(--text-primary);
    font-weight: 600;
    line-height: 1.2;
}

.app-footer {
    flex-shrink: 0;
    text-align: center;
    padding: 0.5rem;
    background: var(--accent-gradient);
    color: white;
    font-size: 0.8rem;
    opacity: 0.95;
    line-height: 1.3;
}

/* Desktop: Offset footer for sidebar */
@media (min-width: 768px) {
    .app-footer {
        margin-left: var(--sidebar-width);
    }
}

.app-footer p {
    margin: 0;
}

.app-footer a {
    color: white;
    text-decoration: underline;
    opacity: 0.9;
    transition: opacity var(--transition-fast);
}

.app-footer a:hover {
    opacity: 1;
}

/* Adjust sidebar to work with header/footer */
.sidebar {
    top: 0;
    height: 100vh;
}

@media (max-width: 767px) {
    .app-header-content {
        padding: 0.4rem 0.8rem;
        gap: 0.5rem;
    }
    
    .app-logo {
        height: 28px;
    }
    
    .app-header-text h1 {
        font-size: 1.1rem;
    }
    
    .app-footer {
        font-size: 0.75rem;
        padding: 0.4rem;
    }
}