/* ==========================================
   GLOBAL STYLES & RESET
   ========================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette */
    --primary-green: #2d5016;
    --secondary-green: #4a7c2c;
    --light-green: #5a9a35;
    --accent-green: #31E20D;
    
    --bar-unsorted: #6495ED;
    --bar-comparing: #FF0000;
    --bar-pivot: #FFD700;
    --bar-sorted: #31E20D;
    
    --bg-light: #f5f5f5;
    --bg-white: #ffffff;
    --text-dark: #333333;
    --text-light: #666666;
    --border-color: #ddd;
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    
    /* Animation */
    --transition-speed: 0.3s;
}

/* Dark Theme Variables */
body.dark-theme {
    --bg-light: #1a1a1a;
    --bg-white: #2d2d2d;
    --text-dark: #e0e0e0;
    --text-light: #a0a0a0;
    --border-color: #444;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-light);
    color: var(--text-dark);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color 0.3s ease;
}

/* ==========================================
   HEADER SECTION
   ========================================== */
.header {
    background: linear-gradient(135deg, var(--primary-green), var(--secondary-green));
    padding: var(--spacing-lg) var(--spacing-xl);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-controls {
    display: flex;
    gap: var(--spacing-sm);
}

.title {
    color: #ffffff;
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    letter-spacing: 1px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
    flex: 1;
}

.theme-toggle {
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.3);
    color: #ffffff;
    padding: 10px 16px;
    border-radius: 50px;
    cursor: pointer;
    font-size: 1.2rem;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

/* ==========================================
   MAIN CONTAINER
   ========================================== */
.main-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-lg);
}

/* ==========================================
   CONTROL BUTTONS SECTION
   ========================================== */
.controls-section {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    margin-bottom: var(--spacing-lg);
    transition: background-color 0.3s ease;
}

.button-group {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    justify-content: center;
}

.control-btn {
    background: linear-gradient(135deg, var(--primary-green), var(--secondary-green));
    color: #ffffff;
    border: none;
    padding: 12px 24px;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 6px;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    min-width: 140px;
}

.control-btn:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--secondary-green), var(--light-green));
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.control-btn:active:not(:disabled) {
    transform: translateY(0);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.control-btn:disabled {
    background: #cccccc;
    cursor: not-allowed;
    opacity: 0.6;
}

/* ==========================================
   VISUALIZATION SECTION
   ========================================== */
.visualization-section {
    background: var(--bg-white);
    padding: var(--spacing-xl);
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    margin-bottom: var(--spacing-lg);
    min-height: 450px;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    transition: background-color 0.3s ease;
}

.bars-container {
    display: flex;
    align-items: flex-end;
    justify-content: center;
    gap: 2px;
    width: 100%;
    height: 400px;
    position: relative;
}

.bar {
    background-color: var(--bar-unsorted);
    transition: all 0.2s ease;
    position: relative;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    border-radius: 2px 2px 0 0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.bar-value {
    position: absolute;
    bottom: -20px;
    font-size: 0.7rem;
    color: var(--text-light);
    font-weight: 500;
}

/* Bar States */
.bar.comparing {
    background-color: var(--bar-comparing);
}

.bar.pivot {
    background-color: var(--bar-pivot);
}

.bar.sorted {
    background-color: var(--bar-sorted);
}

/* ==========================================
   ANIMATION CONTROLS
   ========================================== */
.animation-controls {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    margin-bottom: var(--spacing-lg);
    transition: background-color 0.3s ease;
}

/* Status Info Bar */
.status-info-bar {
    background: linear-gradient(135deg, #e8f5e9, #c8e6c9);
    padding: var(--spacing-md);
    border-radius: 6px;
    margin-bottom: var(--spacing-md);
    border-left: 4px solid var(--secondary-green);
}

.status-group {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    align-items: center;
}

.status-text {
    font-weight: 600;
    color: var(--text-dark);
    font-size: 1rem;
    flex: 1;
    min-width: 200px;
}

.comparison-counter,
.swap-counter {
    font-size: 0.9rem;
    color: var(--text-dark);
    font-weight: 600;
    padding: 4px 12px;
    background: rgba(255, 255, 255, 0.6);
    border-radius: 12px;
}

/* Playback Control Row */
.playback-control-row {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.playback-btn {
    background: linear-gradient(135deg, var(--primary-green), var(--secondary-green));
    color: #ffffff;
    border: none;
    padding: 10px 16px;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 6px;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    display: flex;
    align-items: center;
    gap: 6px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.15);
    min-width: 120px;
    justify-content: center;
}

.playback-btn span {
    font-size: 1rem;
}

.playback-btn:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--secondary-green), var(--light-green));
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.playback-btn:active:not(:disabled) {
    transform: translateY(0);
}

.playback-btn:disabled {
    background: #cccccc;
    cursor: not-allowed;
    opacity: 0.6;
}

/* Speed and Canvas Controls */
.speed-canvas-controls {
    border-top: 2px solid var(--border-color);
    padding-top: var(--spacing-md);
}

.speed-control-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.control-label {
    font-weight: 600;
    color: var(--text-dark);
    font-size: 0.95rem;
    margin-bottom: var(--spacing-xs);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.label-text {
    color: var(--primary-green);
}

.speed-value {
    color: var(--text-light);
    font-size: 0.85rem;
}

/* Slider Styles */
.speed-slider {
    width: 100%;
    height: 8px;
    border-radius: 5px;
    background: linear-gradient(to right, #31E20D 0%, #FFD700 50%, #FF0000 100%);
    outline: none;
    opacity: 0.9;
    transition: opacity 0.2s;
    cursor: pointer;
    margin-bottom: var(--spacing-sm);
}

.speed-slider:hover {
    opacity: 1;
}

.speed-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--secondary-green);
    cursor: pointer;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
    transition: all 0.2s;
}

.speed-slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
    background: var(--light-green);
}

.speed-slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--secondary-green);
    cursor: pointer;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
    border: none;
    transition: all 0.2s;
}

.speed-slider::-moz-range-thumb:hover {
    transform: scale(1.2);
    background: var(--light-green);
}

/* Speed Display Row */
.speed-display {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    font-size: 0.9rem;
    color: var(--text-dark);
}

.speed-display span {
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 6px;
}

.size-input {
    width: 70px;
    padding: 6px 10px;
    border: 2px solid var(--border-color);
    border-radius: 4px;
    font-size: 0.85rem;
    text-align: center;
    background: var(--bg-white);
    color: var(--text-dark);
}

.size-input:focus {
    outline: none;
    border-color: var(--secondary-green);
}

.control-action-btn {
    background: linear-gradient(135deg, var(--primary-green), var(--secondary-green));
    color: #ffffff;
    border: none;
    padding: 8px 16px;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 4px;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.control-action-btn:hover {
    background: linear-gradient(135deg, var(--secondary-green), var(--light-green));
    transform: translateY(-1px);
    box-shadow: 0 3px 6px rgba(0, 0, 0, 0.15);
}

/* Keyboard Shortcuts Section */
.shortcuts-info {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 2px solid var(--border-color);
    text-align: center;
}

.shortcuts-btn {
    background: var(--bg-light);
    border: 2px solid var(--border-color);
    color: var(--text-dark);
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s;
}

.shortcuts-btn:hover {
    background: var(--border-color);
    transform: translateY(-1px);
}

.shortcuts-panel {
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--bg-light);
    border-radius: 6px;
    text-align: left;
}

.shortcuts-panel h4 {
    color: var(--primary-green);
    margin-bottom: var(--spacing-sm);
}

.shortcuts-panel ul {
    list-style: none;
    padding: 0;
}

.shortcuts-panel li {
    padding: var(--spacing-xs) 0;
    color: var(--text-dark);
}

.shortcuts-panel kbd {
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 2px 8px;
    font-family: monospace;
    font-weight: 600;
    margin-right: var(--spacing-sm);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

/* ==========================================
   ALGORITHM INFO SECTION
   ========================================== */
.info-section {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s ease;
}

.info-title {
    color: var(--primary-green);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    border-bottom: 2px solid var(--secondary-green);
    padding-bottom: var(--spacing-sm);
}

.algorithm-info {
    color: var(--text-light);
    line-height: 1.8;
}

.algorithm-info h3 {
    color: var(--secondary-green);
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
}

.algorithm-info h4 {
    color: var(--text-dark);
    font-weight: 600;
    margin-top: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
}

.algorithm-info ul {
    margin-left: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.algorithm-info code {
    background: var(--bg-light);
    padding: 2px 6px;
    border-radius: 3px;
    font-family: 'Courier New', monospace;
    color: var(--primary-green);
}

/* ==========================================
   CUSTOM MODAL
   ========================================== */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
}

.modal.show {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background: var(--bg-white);
    border-radius: 12px;
    width: 90%;
    max-width: 450px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        transform: translateY(-50px) scale(0.9);
        opacity: 0;
    }
    to {
        transform: translateY(0) scale(1);
        opacity: 1;
    }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-lg);
    border-bottom: 2px solid var(--border-color);
    background: linear-gradient(135deg, var(--primary-green), var(--secondary-green));
    border-radius: 12px 12px 0 0;
}

.modal-header h3 {
    color: #ffffff;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0;
}

.modal-close {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    font-size: 1.8rem;
    color: #ffffff;
    cursor: pointer;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s;
}

.modal-close:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: rotate(90deg);
}

.modal-body {
    padding: var(--spacing-xl);
}

.modal-label {
    display: block;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: var(--spacing-md);
    font-size: 1rem;
}

.modal-input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1.1rem;
    text-align: center;
    font-weight: 600;
    transition: all 0.2s;
    margin-bottom: var(--spacing-lg);
    background: var(--bg-white);
    color: var(--text-dark);
}

.modal-input:focus {
    outline: none;
    border-color: var(--secondary-green);
    box-shadow: 0 0 0 3px rgba(74, 124, 44, 0.1);
}

.size-slider-container {
    margin-bottom: var(--spacing-lg);
}

.modal-slider {
    width: 100%;
    height: 10px;
    border-radius: 5px;
    background: linear-gradient(to right, var(--primary-green) 0%, var(--light-green) 100%);
    outline: none;
    cursor: pointer;
    margin-bottom: var(--spacing-sm);
}

.modal-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--secondary-green);
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(74, 124, 44, 0.5);
    transition: all 0.2s;
}

.modal-slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 4px 12px rgba(74, 124, 44, 0.7);
}

.modal-slider::-moz-range-thumb {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--secondary-green);
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(74, 124, 44, 0.5);
    border: none;
    transition: all 0.2s;
}

.modal-slider::-moz-range-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 4px 12px rgba(74, 124, 44, 0.7);
}

.slider-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    color: var(--text-light);
    font-weight: 600;
}

.modal-hint {
    font-size: 1rem;
    color: var(--text-dark);
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: linear-gradient(135deg, #e8f5e9, #c8e6c9);
    border-radius: 8px;
    text-align: center;
    border-left: 4px solid var(--secondary-green);
}

.modal-hint span {
    font-weight: 700;
    color: var(--primary-green);
    font-size: 1.3rem;
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-sm);
    padding: var(--spacing-lg);
    border-top: 2px solid var(--border-color);
    background: var(--bg-light);
    border-radius: 0 0 12px 12px;
}

.modal-btn {
    padding: 12px 28px;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-cancel {
    background: var(--bg-white);
    color: var(--text-dark);
    border: 2px solid var(--border-color);
}

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

.btn-apply {
    background: linear-gradient(135deg, var(--primary-green), var(--secondary-green));
    color: #ffffff;
    box-shadow: 0 2px 8px rgba(74, 124, 44, 0.3);
}

.btn-apply:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(74, 124, 44, 0.4);
}

.btn-apply:active {
    transform: translateY(0);
}

/* ==========================================
   UTILITY CLASSES
   ========================================== */
.hidden {
    display: none !important;
}

.disabled {
    pointer-events: none;
    opacity: 0.5;
}

/* ==========================================
   ANIMATIONS
   ========================================== */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-10px); }
    75% { transform: translateX(10px); }
}

.fade-in {
    animation: fadeIn 0.5s ease;
}