/* CSS Variables */
:root {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --radius: 12px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

/* Container */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.subtitle {
    color: var(--text-muted);
    font-size: 1.1rem;
}

/* Sections */
section {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1rem;
    box-shadow: var(--shadow);
}

/* Upload Area */
.upload-area {
    border: 2px dashed var(--border);
    border-radius: var(--radius);
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--primary);
    background: rgba(37, 99, 235, 0.05);
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.upload-hint {
    color: var(--text-muted);
    margin: 0.5rem 0;
}

.upload-btn {
    display: inline-block;
    background: var(--primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: background 0.2s ease;
}

.upload-btn:hover {
    background: var(--primary-hover);
}

.upload-btn input {
    display: none;
}

.supported-formats {
    margin-top: 1rem;
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* File Info */
.file-info {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(37, 99, 235, 0.1);
    padding: 1rem;
    border-radius: 8px;
    margin-top: 1rem;
}

.file-name {
    font-weight: 500;
    word-break: break-all;
}

.remove-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 1.25rem;
    padding: 0.25rem;
    transition: color 0.2s ease;
}

.remove-btn:hover {
    color: var(--error);
}

/* Options */
.options-section {
    background: transparent;
    box-shadow: none;
    padding: 0.5rem 0;
}

.option label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    color: var(--text-muted);
}

.option input[type="checkbox"] {
    width: 1.1rem;
    height: 1.1rem;
    cursor: pointer;
}

/* Extract Button */
.extract-btn {
    width: 100%;
    background: var(--primary);
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: var(--radius);
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.extract-btn:hover:not(:disabled) {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

.extract-btn:disabled {
    background: var(--border);
    cursor: not-allowed;
}

/* Spinner */
.spinner {
    display: inline-block;
    width: 1rem;
    height: 1rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* Status Section */
.status-section {
    text-align: center;
}

.status-message {
    font-weight: 500;
    margin-bottom: 1rem;
}

.progress-bar {
    height: 6px;
    background: var(--border);
    border-radius: 3px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--primary);
    border-radius: 3px;
    transition: width 0.3s ease;
    animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

/* Results Section */
.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.results-header h2 {
    font-size: 1.25rem;
}

.results-actions {
    display: flex;
    gap: 0.5rem;
}

.action-btn {
    background: var(--bg);
    border: 1px solid var(--border);
    padding: 0.5rem 1rem;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.2s ease;
}

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

.results-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.stat-item {
    background: var(--bg);
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.stat-label {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.results-preview h3,
.results-json h3 {
    font-size: 1rem;
    margin-bottom: 0.75rem;
    color: var(--text-muted);
}

.sections-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-height: 300px;
    overflow-y: auto;
}

.section-item {
    background: var(--bg);
    padding: 0.75rem 1rem;
    border-radius: 6px;
    border-left: 3px solid var(--primary);
}

.section-heading {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.section-words {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.results-json {
    margin-top: 1.5rem;
}

.results-json pre {
    background: #1e293b;
    color: #e2e8f0;
    padding: 1rem;
    border-radius: 8px;
    overflow-x: auto;
    font-size: 0.85rem;
    max-height: 400px;
    overflow-y: auto;
}

/* Error Section */
.error-section {
    text-align: center;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--error);
}

.error-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.error-message {
    color: var(--error);
    font-weight: 500;
    margin-bottom: 1rem;
}

.retry-btn {
    background: var(--error);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: opacity 0.2s ease;
}

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

/* Footer */
footer {
    text-align: center;
    margin-top: 2rem;
    color: var(--text-muted);
    font-size: 0.9rem;
}

footer a {
    color: var(--primary);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background: var(--text);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 500;
    animation: slideUp 0.3s ease;
    z-index: 1000;
}

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

/* Responsive */
@media (max-width: 600px) {
    .container {
        padding: 1rem;
    }
    
    header h1 {
        font-size: 1.5rem;
    }
    
    .upload-area {
        padding: 2rem 1rem;
    }
    
    .results-header {
        flex-direction: column;
        align-items: flex-start;
    }
}