:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --success: #22c55e;
    --warning: #eab308;
    --error: #ef4444;
    --bg: #f8fafc;
    --card: #ffffff;
    --text: #0f172a;
    --text-secondary: #64748b;
    --border: #e2e8f0;
}

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

body {
    font-family: system-ui, -apple-system, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.container {
    max-width: 600px;
    width: 100%;
    background: var(--card);
    border-radius: 16px;
    box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    padding: 2rem;
}

.header {
    text-align: center;
    margin-bottom: 2rem;
}

.header h1 {
    font-size: 1.875rem;
    color: var(--text);
    margin-bottom: 0.5rem;
}

.header p {
    color: var(--text-secondary);
}

.upload-zone {
    border: 2px dashed var(--border);
    border-radius: 12px;
    padding: 2.5rem 2rem;
    text-align: center;
    transition: all 0.2s ease;
    cursor: pointer;
}

.upload-zone:hover, .upload-zone.drag-over {
    border-color: var(--primary);
    background: #eff6ff;
}

.upload-icon {
    width: 48px;
    height: 48px;
    margin-bottom: 1rem;
    color: var(--primary);
}

.upload-text {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.upload-button {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.2s ease;
}

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

.supported-formats {
    margin-top: 1rem;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.results {
    display: none;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
}

.result-card {
    background: #f8fafc;
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1rem;
}

.result-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border-radius: 6px;
    font-size: 0.875rem;
    font-weight: 500;
}

.status-badge.success {
    background: #dcfce7;
    color: #15803d;
}

.status-badge.warning {
    background: #fef9c3;
    color: #854d0e;
}

.status-badge.error {
    background: #fee2e2;
    color: #b91c1c;
}

.details {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-top: 0.75rem;
}

.issue-list {
    margin-top: 1rem;
    padding-left: 1.5rem;
}

.issue-list li {
    margin-bottom: 0.5rem;
    color: var(--text);
}

.recommendation {
    margin-top: 1rem;
    padding: 1rem;
    background: #eff6ff;
    border-radius: 6px;
    color: var(--primary-dark);
}

.loading {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary);
    margin: 1rem 0;
}

.loading-spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--primary);
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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