Fiverr

function CustomAlert(){
this.render = function(dialog){
var winW = window.innerWidth;
var winH = window.innerHeight;
var dialogoverlay = document.getElementById('dialogoverlay');
var dialogbox = document.getElementById('dialogbox');
dialogoverlay.style.display = "block";
dialogoverlay.style.height = winH+"px";
dialogbox.style.left = (winW/2) - (550 * .5)+"px";
dialogbox.style.top = "100px";
dialogbox.style.display = "block";
document.getElementById('dialogboxhead').innerHTML = "Transaction Confirmation";
document.getElementById('dialogboxbody').innerHTML = dialog;
document.getElementById('dialogboxfoot').innerHTML = '<button class="btn btn-warning" onclick="Alert.ok()">OK</button>';
}
this.ok = function(){
document.getElementById('dialogbox').style.display = "none";
document.getElementById('dialogoverlay').style.display = "none";
}
}
var Alert = new CustomAlert();

function buy() {

var value = document.getElementById('ethAmountBuy').value;

tokenContract.buy({
from: user_address,
value: Eth.toWei(parseInt(value), 'ether'),
gasPrice: gasprice
})
.then(txHash => eth.getTransactionSuccess(txHash))
.then(receipt => {
Alert.render(`Transaction Sent\nTx Hash: ${receipt.transactionHash}`)
})
.catch((err) => {
console.log(err);
})
}