How to put button at the bottom-right of the box - html

Question

I'm just wondering how I can put my button at the right-bottom of the parent box.
I have put position: relative; to the parent box and used position: absolute; for the button class.
This worked perfectly. However, the button overlapped with the contents of the parent box.
What would be the best way to fix this?
Here's my html and css Thank you!!
.color {
border: 1px solid black;
width: 70%;
margin: 10px auto;
padding: 0 30px;
position: relative;
}
.color p {
display: inline-block;
width: 200px;
height: 80px;
margin-right: 10px;
text-align: center;
line-height: 78px;
}
p.black {
background: black;
color: white;
}
p.gray {
background: gray;
color: white;
}
p.blue {
background: blue;
color: white;
}
p.white {
border: 1px solid black;
}
.btn {
position: absolute;
right: 10px;
bottom: 10px;
}
.btn a {
display: inline-block;
background: #efd9ca;
padding: 25px;
width: 300px;
text-align: center;
text-decoration: none;
}
<h1 class="heading">color</h1>
<p class="black">black</p>
<p class="gray">gray</p>
<p class="white">white</p>
<p class="blue">blue</p>
<div class="btn">Mozilla color collection website</div>

Answer 1

I removed your relative and absolute position declarations. Then I added following css declrations:
.btn {
float: right;
margin-bottom: -20px;
}
float: right; will align the button to the right side. With margin-bottom: -20px; you counter the padding bottom of 30px so that the spacing will only be 10px as previos attempted.
.color {
border: 1px solid black;
width: 70%;
margin: 10px auto;
padding: 0 30px;
}
.color p {
display: inline-block;
width: 200px;
height: 80px;
margin-right: 10px;
text-align: center;
line-height: 78px;
}
p.black {
background: black;
color: white;
}
p.gray {
background: gray;
color: white;
}
p.blue {
background: blue;
color: white;
}
p.white {
border: 1px solid black;
}
.btn a {
display: inline-block;
background: #efd9ca;
padding: 25px;
width: 300px;
text-align: center;
text-decoration: none;
}
.btn {
float: right;
margin-bottom: -20px;
}
<h1 class="heading">color</h1>
<p class="black">black</p>
<p class="gray">gray</p>
<p class="white">white</p>
<p class="blue">blue</p>
<div class="btn">Mozilla color collection website</div>