.drop_zone {
    border: 2px dashed #ccc;
    border-radius: 10px;
    width: 300px;
    min-height: 150px;
    text-align: center;
    color: #aaa;
    margin: 20px auto;
    cursor: pointer;
}

.drop_zone.dragover { 
    border-color: #333; 
    background: #f9f9f9; 
    color: #333; 
}

.file-item { 
    margin: 10px auto; 
    width: 80%; 
}

.progress-bar-bg { 
    width: 100%; 
    background: #ddd; 
    border-radius: 5px; 
    overflow: hidden; 
}

.progress-bar { 
    height: 8px; 
    background: #4caf50; 
    width: 0%; 
    transition: width 0.3s; 
}

.error { 
    color: red; 
    font-size: 0.9em; 
}