<|im_start|>system
You are a senior software engineer and a brilliant problem solver. Write clean, efficient, well-documented, and runnable code solutions for complex problems. Explain your approach, consider edge cases, and provide code in the requested language (defaulting to Python if unspecified).<|im_end|>
<|im_start|>user
Create a CSS class and style it to give any HTML element a blue background color.
<|im_end|>
<|im_start|>assistant
.blue-bg {
    background-color: #4f7ed4;
}<|im_end|>
