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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: #f5f7fa;
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.header {
    background: #2c3e50;
    color: white;
    padding: 32px 40px;
    border-bottom: 3px solid #3498db;
}

.header h1 {
    font-size: 1.75em;
    margin-bottom: 8px;
    font-weight: 600;
}

.header p {
    font-size: 0.95em;
    opacity: 0.85;
    color: #ecf0f1;
}

.content {
    padding: 40px;
}

.tabs {
    display: flex;
    gap: 0;
    margin-bottom: 30px;
    border-bottom: 1px solid #e1e8ed;
}

.tab {
    padding: 12px 24px;
    background: none;
    border: none;
    font-size: 0.95em;
    cursor: pointer;
    color: #657786;
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
    font-weight: 500;
}

.tab:hover {
    color: #3498db;
    background: #f7f9fa;
}

.tab.active {
    color: #3498db;
    border-bottom-color: #3498db;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.3s;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.upload-area {
    border: 2px dashed #cbd6e2;
    border-radius: 8px;
    padding: 60px 40px;
    text-align: center;
    background: #f8fafb;
    cursor: pointer;
    transition: all 0.2s;
    margin-bottom: 20px;
}

.upload-area:hover, .upload-area.drag-over {
    border-color: #3498db;
    background: #f0f8ff;
}

.upload-icon {
    font-size: 3.5em;
    margin-bottom: 16px;
    opacity: 0.6;
}

.upload-area h3 {
    color: #2c3e50;
    margin-bottom: 8px;
    font-size: 1.25em;
    font-weight: 600;
}

.upload-area p {
    color: #657786;
    font-size: 0.9em;
}

.file-input {
    display: none;
}

.url-input-group {
    margin-bottom: 20px;
}

.url-input-group label {
    display: block;
    margin-bottom: 10px;
    color: #2c3e50;
    font-weight: 600;
    font-size: 1em;
}

.url-input {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #cbd6e2;
    border-radius: 6px;
    font-size: 0.95em;
    transition: all 0.2s;
}

.url-input:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.file-type-select {
    margin-top: 15px;
}

.file-type-select label {
    display: block;
    margin-bottom: 8px;
    color: #657786;
    font-size: 0.9em;
}

.radio-group {
    display: flex;
    gap: 20px;
}

.radio-group label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    color: #2c3e50;
    font-size: 0.9em;
}

.radio-group input[type="radio"] {
    cursor: pointer;
}

.btn {
    display: inline-block;
    padding: 12px 32px;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 0.95em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn:hover {
    background: #2980b9;
}

.btn:active {
    transform: translateY(1px);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.result {
    margin-top: 24px;
    padding: 16px 20px;
    border-radius: 6px;
    display: none;
    border-left: 4px solid;
}

.result.success {
    background: #eafaf1;
    border-color: #27ae60;
    color: #1e6f4e;
}

.result.error {
    background: #fef5f5;
    border-color: #e74c3c;
    color: #c0392b;
}

.result h4 {
    margin-bottom: 8px;
    font-size: 1em;
    font-weight: 600;
}

.result p {
    font-size: 0.9em;
    line-height: 1.5;
}

.result a {
    color: #3498db;
    font-weight: 600;
    text-decoration: none;
}

.result a:hover {
    text-decoration: underline;
}

.info-section {
    background: #f8fafb;
    padding: 20px 24px;
    border-radius: 6px;
    margin-top: 24px;
    border: 1px solid #e1e8ed;
}

.info-section h3 {
    color: #2c3e50;
    margin-bottom: 12px;
    font-size: 1.1em;
    font-weight: 600;
}

.info-section ul, .info-section ol {
    margin-left: 20px;
    color: #657786;
    line-height: 1.8;
}

.info-section code {
    background: #ecf0f1;
    padding: 2px 6px;
    border-radius: 3px;
    font-family: 'Monaco', 'Menlo', 'Courier New', monospace;
    color: #e74c3c;
    font-size: 0.85em;
}

.loading {
    display: none;
    text-align: center;
    margin-top: 20px;
}

.spinner {
    border: 3px solid #ecf0f1;
    border-top: 3px solid #3498db;
    border-radius: 50%;
    width: 36px;
    height: 36px;
    animation: spin 0.8s linear infinite;
    margin: 0 auto;
}

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

.selected-file {
    margin-top: 15px;
    padding: 12px 16px;
    background: #f0f8ff;
    border: 1px solid #3498db;
    border-radius: 6px;
    display: none;
}

.selected-file.show {
    display: block;
}

.selected-file strong {
    color: #2c3e50;
}