.row-width {
  margin: 0 auto; max-width:920px;
}
.file-viewer-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    padding: 20px;
}

.file-viewer-container {
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    max-width: 500px;
    width: 100%;
}

.file-viewer-container h1 {
    color: #333;
    margin-bottom: 10px;
    font-size: 28px;
    text-align: center;
}

.file-viewer-subtitle {
    color: #666;
    text-align: center;
    margin-bottom: 30px;
    font-size: 14px;
}

.fv-upload-area {
    border: 2px dashed #667eea;
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    background: #f8f9ff;
}

.fv-upload-area:hover {
    border-color: #764ba2;
    background: #f0f2ff;
}

.fv-upload-area.dragover {
    border-color: #764ba2;
    background: #e8ebff;
    transform: scale(1.02);
}

.fv-upload-icon {
    font-size: 50px;
    color: #667eea;
    margin-bottom: 20px;
}

.fv-upload-text {
    color: #333;
    font-size: 16px;
    margin-bottom: 10px;
}

.fv-upload-hint {
    color: #999;
    font-size: 12px;
}

#fileInput {
    display: none;
}

.fv-file-info {
    margin-top: 20px;
    padding: 15px;
    background: #f0f2ff;
    border-radius: 10px;
    display: none;
}

.fv-file-info.show {
    display: block;
}

.fv-file-name {
    color: #333;
    font-weight: bold;
    margin-bottom: 5px;
}

.fv-file-size {
    color: #666;
    font-size: 14px;
}

.fv-btn-submit {
    width: 100%;
    padding: 15px;
    margin-top: 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: transform 0.2s ease;
    display: none;
}

.fv-btn-submit.show {
    display: block;
}

.fv-btn-submit:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

.fv-btn-submit:active {
    transform: translateY(0);
}

.fv-btn-submit:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

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

.fv-loading.show {
    display: block;
}

.fv-spinner {
    border: 3px solid #f3f3f3;
    border-top: 3px solid #667eea;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: fv-spin 1s linear infinite;
    margin: 0 auto;
}

.fv-progress-container {
    width: 100%;
    height: 8px;
    background: #e0e0e0;
    border-radius: 10px;
    overflow: hidden;
    margin-top: 15px;
    display: none;
}

.fv-progress-container.show {
    display: block;
}

.fv-progress-bar {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    width: 0%;
    transition: width 0.3s ease;
    border-radius: 10px;
}

.fv-progress-text {
    text-align: center;
    margin-top: 8px;
    color: #667eea;
    font-size: 14px;
    font-weight: bold;
}

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

.fv-error {
    background: #fee;
    color: #c33;
    padding: 15px;
    border-radius: 10px;
    margin-top: 20px;
    display: none;
}

.fv-error.show {
    display: block;
}

.fv-response-container {
    width: 100%;
    max-width: 1400px;
    margin-top: 20px;
    padding: 30px;
    border: 2px solid #667eea;
    background: linear-gradient(135deg, #f8f9ff 0%, #f0f2ff 100%);
    box-shadow: 0 10px 40px rgba(102, 126, 234, 0.15);
    border-radius: 15px;
}

.fv-response-title {
    margin: 0 0 20px 0;
    color: #667eea;
    font-size: 24px;
    font-weight: bold;
    border-bottom: 2px solid #667eea;
    padding-bottom: 10px;
}

.fv-response-content {
    padding: 20px;
    background: white;
    border: 1px solid #e0e4f0;
    min-height: 150px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    font-size: 16px;
    line-height: 1.6;
    color: #333;
}