Hi,
THE BEST site for SSL explanation.
The experience will be even better if you can differentiate different parts the req/resp message hex parts.
I'm overriding site styles with below:
.record-data .string {
background-color: lightsalmon;
}
.record-data .string:nth-child(even) {
background-color: lightseagreen;
}
After which, the Hex dump will be even clear (if required, you can add a toggle button):

Thanks.