:root {
    --primary-color: #2c3e50;
    --accent-color: #3498db;
    --background-color: #f5f6fa;
    --text-color: #2c3e50;
    --border-color: #dcdde1;
    --error-color: #e74c3c;
    --error-bg: #fde8e8;
}

body {
    font-family: 'Segoe UI', system-ui, sans-serif;
    margin: 0;
    padding: 0;
    background: var(--background-color);
    color: var(--text-color);
}

.container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
}

h1 {
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 2rem;
}

.input-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

.sources-container, .analysis-options {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.source-entry {
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: 1rem;
    margin-bottom: 1rem;
    padding: 1rem;
    background: var(--background-color);
    border-radius: 4px;
}

.source-entry.pdf-source {
    background: #e8f5fe;
}

.source-entry textarea {
    width: 100%;
    min-height: 100px;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    resize: vertical;
}

.button {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s ease;
    background: var(--background-color);
    color: var(--text-color);
}

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

.button.primary {
    background: var(--accent-color);
    color: white;
    font-size: 1.1rem;
    padding: 0.75rem 1.5rem;
    width: 100%;
    max-width: 300px;
    margin: 0 auto;
    display: block;
}

.button.primary:hover {
    background: #2980b9;
}

.source-type-selector {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
}

.source-type-selector button {
    flex: 1;
    padding: 0.5rem;
    background: var(--background-color);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    cursor: pointer;
}

.source-type-selector button.active {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.file-upload {
    display: none;
}

.pdf-preview {
    padding: 0.5rem;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 0.9rem;
}

.error-message {
    color: var(--error-color);
    background: var(--error-bg);
    padding: 0.75rem;
    border-radius: 4px;
    margin: 0.5rem 0;
    display: none;
}

.error-message.visible {
    display: block;
}

.error {
    color: #e74c3c;
    padding: 1rem;
    background: #fde8e8;
    border-radius: 4px;
    margin: 1rem 0;
}

.output-section {
    margin-top: 2rem;
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.loading-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--background-color);
    border-top: 4px solid var(--accent-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.hidden {
    display: none;
}

#results {
    white-space: pre-wrap;
    line-height: 1.6;
}

#results .citation {
    color: var(--accent-color);
    font-weight: 500;
}

#results h2 {
    color: var(--primary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
    margin-top: 2rem;
}

#results .references {
    margin-top: 2rem;
    padding-top: 1rem;
    border-top: 2px solid var(--border-color);
}

#results .references h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

#results .references p {
    margin: 0.5rem 0;
    padding-left: 2rem;
    text-indent: -2rem;
}

#focusAreas {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
}

#focusAreas label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

select {
    width: 100%;
    padding: 0.5rem;
    margin-bottom: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

.results-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 2rem;
}

#downloadPdf {
    display: flex;
    align-items: center;
    background: var(--accent-color);
    color: white;
    padding: 0.75rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.3s ease;
}

#downloadPdf:hover {
    background: #2980b9;
}

#downloadPdf svg {
    margin-right: 8px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

@media (max-width: 768px) {
    .input-section {
        grid-template-columns: 1fr;
    }
}