/* CSS Variables for theming */
:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --border-color: #dee2e6;
    --accent-color: #0d6efd;
    --accent-hover: #0b5ed7;
    --success-color: #198754;
    --danger-color: #dc3545;
    --added-bg: #d1f4e0;
    --added-text: #0c5132;
    --removed-bg: #f8d7da;
    --removed-text: #842029;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --bg-primary: #1a1d23;
    --bg-secondary: #22262e;
    --bg-tertiary: #2c3039;
    --text-primary: #e9ecef;
    --text-secondary: #adb5bd;
    --border-color: #3a3f4b;
    --accent-color: #3d8bfd;
    --accent-hover: #5a9fff;
    --added-bg: #1a4d2e;
    --added-text: #a7f3d0;
    --removed-bg: #5a1a1a;
    --removed-text: #fca5a5;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: 20px 0;
    text-align: center;
    box-shadow: var(--shadow);
}

header h1 {
    font-size: 2rem;
    margin-bottom: 5px;
    color: var(--text-primary);
}

.tagline {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Controls */
.controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 15px;
    margin: 20px 0;
    flex-wrap: wrap;
}

.control-group {
    display: flex;
    gap: 10px;
    align-items: center;
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 6px;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-primary {
    background-color: var(--accent-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

.btn-secondary {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

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

.btn-icon {
    padding: 8px 12px;
    font-size: 1.2rem;
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-color);
}

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

/* Labels and checkboxes */
label {
    display: flex;
    align-items: center;
    gap: 5px;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 0.9rem;
}

input[type="checkbox"] {
    cursor: pointer;
}

/* Editor Container */
.editor-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 30px;
}

.editor-panel {
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background-color: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
}

.panel-header h2 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.char-count {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.text-input {
    width: 100%;
    min-height: 300px;
    padding: 16px;
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
    border: none;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    resize: vertical;
    outline: none;
}

.text-input::placeholder {
    color: var(--text-secondary);
}

/* Results Section */
.results-section {
    background-color: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 30px;
    box-shadow: var(--shadow);
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 15px;
}

.results-header h2 {
    font-size: 1.3rem;
}

.stats {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

.stat {
    padding: 5px 12px;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
}

.stat-added {
    background-color: var(--added-bg);
    color: var(--added-text);
}

.stat-removed {
    background-color: var(--removed-bg);
    color: var(--removed-text);
}

.stat-unchanged {
    background-color: var(--bg-tertiary);
    color: var(--text-secondary);
}

/* Diff Output */
.diff-output {
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.8;
    white-space: pre-wrap;
    word-wrap: break-word;
    max-height: 600px;
    overflow-y: auto;
    padding: 16px;
    background-color: var(--bg-secondary);
    border-radius: 6px;
    border: 1px solid var(--border-color);
}

.diff-line {
    padding: 2px 8px;
    margin: 2px 0;
    border-radius: 3px;
}

.diff-added {
    background-color: var(--added-bg);
    color: var(--added-text);
}

.diff-removed {
    background-color: var(--removed-bg);
    color: var(--removed-text);
}

.diff-unchanged {
    color: var(--text-secondary);
}

/* Features Section */
.features {
    margin: 50px 0;
}

.features h2 {
    text-align: center;
    font-size: 1.8rem;
    margin-bottom: 30px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
}

.feature-card {
    background-color: var(--bg-primary);
    padding: 25px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    text-align: center;
    box-shadow: var(--shadow);
    transition: transform 0.2s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.feature-card h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Use Cases */
.use-cases {
    background-color: var(--bg-primary);
    padding: 30px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    margin-bottom: 50px;
    box-shadow: var(--shadow);
}

.use-cases h2 {
    font-size: 1.5rem;
    margin-bottom: 20px;
}

.use-cases ul {
    list-style: none;
}

.use-cases li {
    padding: 12px 0;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.use-cases li:last-child {
    border-bottom: none;
}

.use-cases strong {
    color: var(--text-primary);
    font-weight: 600;
}

/* Footer */
footer {
    background-color: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    padding: 30px 0;
    text-align: center;
    margin-top: 50px;
}

footer p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin: 5px 0;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s;
}

.footer-links a:hover {
    color: var(--accent-color);
}

/* Responsive Design */
@media (max-width: 768px) {
    .editor-container {
        grid-template-columns: 1fr;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .controls {
        flex-direction: column;
        align-items: stretch;
    }

    .control-group {
        justify-content: center;
    }

    .results-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .feature-grid {
        grid-template-columns: 1fr;
    }
}

/* Scrollbar styling */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 5px;
}

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

/* Line numbers and gutter */
.diff-wrap { 
    position: relative; 
    font-family: 'Consolas','Monaco','Courier New',monospace; 
}

.diff-line { 
    display: grid; 
    grid-template-columns: 56px 1fr; 
    gap: 8px; 
    padding: 2px 6px; 
    border-radius: 4px; 
}

.gutter { 
    text-align: right; 
    color: var(--text-secondary); 
    user-select: none; 
    padding-right: 6px; 
    border-right: 1px solid var(--border-color); 
    font-size: 0.8rem;
}

.gutter.add { 
    color: var(--success-color); 
}

.gutter.rem { 
    color: var(--danger-color); 
}

/* Inline tokens */
.token { 
    padding: 0 2px; 
    border-radius: 3px; 
}

.token.add { 
    background: var(--added-bg); 
    color: var(--added-text); 
}

.token.rem { 
    background: var(--removed-bg); 
    color: var(--removed-text); 
}

/* Unchanged dim */
.diff-unchanged { 
    color: var(--text-secondary); 
}

/* Side-by-side vs unified */
.diff-container-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

#diffLeft, #diffRight { 
    max-height: 600px; 
    overflow: auto; 
    background: var(--bg-secondary); 
    border: 1px solid var(--border-color); 
    border-radius: 6px; 
    padding: 10px; 
}

#diffUnified { 
    max-height: 600px; 
    overflow: auto; 
    background: var(--bg-secondary); 
    border: 1px solid var(--border-color); 
    border-radius: 6px; 
    padding: 10px; 
    grid-column: 1 / -1;
}

/* Header buttons in controls */
.controls .btn-small { 
    padding: 8px 12px; 
    font-size: 0.85rem; 
}

/* Select styling */
select.btn {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23666' d='M6 9L1 4h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 8px center;
    padding-right: 28px;
}

/* Hover help */
.diff-line:hover { 
    background: rgba(0,0,0,0.03); 
}

[data-theme="dark"] .diff-line:hover {
    background: rgba(255,255,255,0.05);
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .diff-container-wrapper {
        grid-template-columns: 1fr;
    }
    
    .controls .btn-small {
        font-size: 0.8rem;
        padding: 6px 10px;
    }
}