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                        /网页广告特效

<!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>顶部广告展开收起</title> <style> body, div, img, span { margin:0; padding:0; } #content{ width:960px; height:1000px; background:#ccc; margin:0 auto; } #ad{ width:960px; margin:0 auto; position: rel