how to make buttons side by side html

1/* HTML
2   <div class="button-container">
3   <div class="button1">
4   BUTTON1
5   </div>
6   <div class="button2">
7   BUTTON2
8   </div>
9</div>
10*/
11
12.button-container{
13  border: 1px solid pink;
14  height: 100px;
15  width: 100%;
16  display: flex;
17  align-content: center;
18  justify-content: center;
19  padding: 4px 4px 4px 4px;
20}
21.button1{
22  border: 1px solid blue;
23  height: 80px;
24  width: 40%;
25  background-color: blue;
26   text-align: center;
27  font-size: 20px;
28  color: white;
29  line-height: 80px;
30  font-weight: 600;
31  }
32  
33  .button2{
34  border: 1px solid red;
35  height: 80px;
36  width: 40%;
37  text-align: center;
38  font-size: 20px;
39  color: white;
40  line-height: 80px;
41  font-weight: 600;
42  background-color: red;
43  }

1.buttons {
2  width: 50px;
3  margin: 0 auto;
4}
5
6.action_btn {
7  display: inline-block;
8  width: calc(50% - 4px);
9  margin: 0 auto;
10}