website_example_email.rule

srl: begin with any of (digit, letter, one of "._%+-") once or more, literally "@", any of (digit, letter, one of ".-") once or more, literally ".", letter at least 2 times, must end, case insensitive
match: "you@example.com"
match: "you@example.email"
match: "me@foo.bar.email"
no match: "you@example.c"
no match: "you@example"
no match: "you@.com"
no match: "@example.com"
no match: "example.com"