var wsdfyy_icp = {"3338999.net":{"icp":"晋ICP备16002659号-2","gaba":""},"3338999.com":{"icp":"晋ICP备16002659号-4","gaba":""},"0357yy.com":{"icp":"晋ICP备16002659号-1","gaba":""},"3338999.com.cn":{"icp":"晋ICP备16002659号-3","gaba":""}}
 
function getMainHost() {
    let key = `mh_${Math.random()}`;
    let keyR = new RegExp(`(^|;)\\s*${key}=12345`);
    let expiredTime = new Date(0);
    let domain = document.domain;
    let domainList = domain.split('.');

    let urlItems = [];
    urlItems.unshift(domainList.pop());
    while (domainList.length) {
        urlItems.unshift(domainList.pop());
        let mainHost = urlItems.join('.');
        let cookie = `${key}=${12345};domain=.${mainHost}`;

        document.cookie = cookie;

        //如果cookie存在，则说明域名合法
        if (keyR.test(document.cookie)) {
            document.cookie = `${cookie};expires=${expiredTime}`;
            return mainHost;
        }
    }
}
console.log(getMainHost())
 
    

    console.log(wsdfyy_icp[getMainHost()].icp)
    document.write('<a href="https://beian.miit.gov.cn" rel="nofollow" target="_blank" style="color:#7d7b7b"> ' + wsdfyy_icp[getMainHost()].icp + '</a>');