document.all.l1_img_1.style.width = "1710px";
document.all.l1_img_2.style.width = "1710px";
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火狐和chrome不支持document.all请用document.getElementById、或document.getElementsByName
html网页可以参考W3C标准 http://www.w3school.com.cn/w3c/w3c_html.asp
将document.all改为document.getElementById("控件id")或者是document.getElementsByName("控件name")
