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About CSS Preprocessors
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<div>Bạn có thể sử dụng thuộc tính overflow khi muốn kiểm soát bố cục tốt hơn. Thuộc tính overflow chỉ định điều gì sẽ xảy ra nếu nội dung tràn ra ngoài hộp của phần tử</div>