More Accessable Web Application

when user using screen reader hover on the checkbox, they will only hear checkbox
```
<input type="checkbox" checked>Sign up
```

add a label around it making it more accessable

<input id="sign-up" type="checkbox" checked>
<label for="sign-up">
  Sign up
<label>

<!-- or -->
<label>
  <input id="sign-up" type="checkbox" checked> Sign up
<label>

label button

<button class="menu" aria-label="menu"></button>

<h2 id="sec1">Section</h2>
<div role="button" tabindex="0" class="button"
  aria-labelledby="sec1 sec1-shop-now" id="sec1-shop-now">Shop Now</div>

2017-1-29