How to get a list of utxos for an address?

Is there any way to use bitcore from a browser to get a list of unspent outputs for an address?
And to broadcast a transaction?

I’d like to make a simple JS app that can be used from a browser to create an unsigned transaction and then use it on an offline computer to sign and then bring back to an online computer to broadcast the transaction.

Currently the way to do this is to query an Insight server with bitcore-explorers as connecting to the p2p network isn’t supported in a browser yet.

Thanks! That looks like exactly what I want. But it doesn’t seem to work.
I went to the bitcore play ground and typed this into the Chrome JS console:

var Insight = require(‘bitcore-explorers’).Insight;
var insight = new Insight();
insight.getUnspentUtxos(‘1CjyU7Z6NCt1qBY6wdoxyvUS5RfLU19mW5’, function(err, utxos) { console.log(utxos, err); });

but it output an empty array and null as err. Even though there is an unspent output in the address.
https://insight.bitpay.com/address/1CjyU7Z6NCt1qBY6wdoxyvUS5RfLU19mW5

Oh, I guess it defaults to testnet!
Like this it worked:

var Insight = require('bitcore-explorers').Insight;
var insight = new Insight('https://insight.bitpay.com','livenet');
insight.getUnspentUtxos('1CjyU7Z6NCt1qBY6wdoxyvUS5RfLU19mW5', function(err, utxos) { console.log(utxos, err); });