How to triangle top and bottom border? - css

Question

As you can see in the image below, I am trying to warp or triangle my div from bottom and top, but I have no idea how to do it. I just tried a couple of times to do it, but I couldn't achieve the result. So how can I make it using after,before psuedo? It doesn't matter make with psuedo, but I wonder that how to do it?
Here is my code:
body{
background:lightblue;;
}
.block{
background-image: linear-gradient(to right, #314b56, #283b44, #1f2c32, #161e21, #0a0f11);
border: 1px solid #fff;
width: 300px;
height: 150px;
margin: 30px;
}
<div class="block"></div>

Answer 1

An idea using transformation and perspective where you will have the border, border-radius also the gradient:
body {
background: lightblue;
}
.block {
overflow: hidden;
width: 300px;
height: 200px;
margin: 20px;
position: relative;
z-index:0;
}
.block::before,
.block::after {
content: "";
position: absolute;
z-index:-1;
border: 1px solid #fff;
top: 0;
bottom: 0;
width: 50%;
background-image: linear-gradient(to right, #314b56, #283b44, #1f2c32, #161e21, #0a0f11);
background-size: 200% 100%;
}
.block::before {
left: 0;
border-right: 0;
border-radius: 15px 0 0 15px;
transform-origin: right;
transform: perspective(100px) rotateY(-5deg);
}
.block::after {
right: 0;
border-left: 0;
border-radius: 0 15px 15px 0;
transform-origin: left;
transform: perspective(100px) rotateY(5deg);
background-position: right;
}
<div class="block"></div>
You can also add the shadow and easily change the gradient:
body {
background: lightblue;
}
.block {
overflow: hidden;
width: 300px;
height: 200px;
margin: 20px;
position: relative;
z-index:0;
filter:drop-shadow(0 0 5px #000);
}
.block::before,
.block::after {
content: "";
position: absolute;
z-index:-1;
border: 1px solid #fff;
top: 0;
bottom: 0;
width: 50%;
background-image: linear-gradient(35deg, blue, red);
background-size: 200% 100%;
}
.block::before {
left: 0;
border-right: 0;
border-radius: 15px 0 0 15px;
transform-origin: right;
transform: perspective(100px) rotateY(-5deg);
}
.block::after {
right: 0;
border-left: 0;
border-radius: 0 15px 15px 0;
transform-origin: left;
transform: perspective(100px) rotateY(5deg);
background-position: right;
}
<div class="block"></div>

Answer 2

You can do it with clip-path. There is a really simple tool that could help you: https://bennettfeely.com/clippy/.
I've made an example for you with your content:
body {
background: lightblue;
}
.block {
background-image: linear-gradient(to right, #314b56, #283b44, #1f2c32, #161e21, #0a0f11);
border: 1px solid #fff;
width: 300px;
height: 150px;
margin: 30px;
-webkit-clip-path: polygon(100% 80%, 50% 100%, 0 80%, 0 20%, 51% 0, 100% 20%);
clip-path: polygon(100% 80%, 50% 100%, 0 80%, 0 20%, 51% 0, 100% 20%);
}
<div class="block"></div>

Answer 3

This can be done using CSS triangles on the ::before and ::after pseudo-elements! I've colored them brightly so you can tell what's happening, but it should be somewhat easy to get these to look they way you want.
body {
background: lightblue;
}
.block {
background-image: linear-gradient(to right, #314b56, #283b44, #1f2c32, #161e21, #0a0f11);
border: 1px solid #fff;
width: 300px;
height: 150px;
margin: 30px;
position: relative;
}
.block::before,
.block::after{
display: block;
content: '';
position: absolute;
border: 150px solid transparent;
}
.block::before {
border-top-width: 0;
border-bottom-width: 25px;
border-bottom-color: red;
top: -25px;
}
.block::after {
border-bottom-width: 0;
border-top-width: 25px;
border-top-color: green;
bottom: -25px;
}
<div class="block"></div>

Answer 4

Adjust the measurements to fit your exact shape requirements. This gives something close to what you are looking for.
body{
background:lightblue;;
}
.block{ position:
relative; width:200px;
height: 150px;
margin: 20px 0;
background: red;
border-radius: 50% / 10%;
background-image: linear-gradient(to right, #314b56, #283b44, #1f2c32, #161e21, #0a0f11);:
}
}
.block:before
{ content: '';
position: absolute;
top: 20%;
bottom: 20%;
right: -5%;
left: -5%;
background: inherit;
border-radius: 5% / 50%;
}
<div class="block"></div>