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csslinear-gradientsradial-gradients

Drawing a bubble reflection with gradients

Happy new year! Im trying to substitute this background picture with a css for scaling purposes. background for a botton

Im having a problem with gradients logic.

the div properties:

.bg {
   border: 1px solid white;
   border-radius:10px;
   padding:10px;
   width:100%;
}

then im trying to color it

the background color is #065BDB the 'bubble reflection' color is a gradient from rgba(87,144,231,1) to rgba(87,144,231,0) - same color with fading opacity.

to make the right shape of the 'bubble' i need to draw circle-square-circle with gradients, the circles draw ok, but the rectangle is problemetic

background:
radial-gradient(2em 2em at 3% 25%, rgba(87,144,231,1) 50%, transparent 50%),
linear-gradient(to bottom, transparent 3%, rgba(87,144,231,1) , transparent 97%),
radial-gradient(2em 2em at 97% 25%, rgba(87,144,231,1) 50%, transparent 50%);

im having multiple issues with this, cannot figure out how to draw a square from top to bottom with a margin on left and right, and how to add transparency from top to bottom to it, + adding a seconds background, maybe its better to make 2 divs instead of 1.

Solution

  • You can rely on a pseudo element and easily obtain the result:

    .bg {
  border: 1px solid white;
  border-radius: 50px;
  height:60px;
  background: #065BDB;
  position:relative;
  z-index:0;
}
.bg::before {
  content:"";
  position:absolute;
  z-index:-1;
  top:5px;
  left:15px;
  right:15px;
  height:30px;
  border-radius:inherit;
  background:linear-gradient(to bottom, rgba(87,144,231,1), rgba(87,144,231,0));

}
    <div class="bg">
</div>

    With multiple background you can try this:

    .bg {
  border: 1px solid white;
  border-radius: 50px;
  height:60px;
  background: 
    radial-gradient(30px 30px at right,transparent 50%, #065BDB 52%)  0% 10px/35px 30px,
    radial-gradient(30px 30px at left,transparent 50%, #065BDB 52%) 100% 10px/35px 30px,
    linear-gradient(to bottom, rgba(87,144,231,1), rgba(87,144,231,0)) 0 10px/100% 30px,
    #065BDB;
  background-repeat:no-repeat;
  box-sizing:border-box;
}
    <div class="bg"></div>

    We can add some CSS variable to control the shape:

    .bg {
  --h:30px; /*the height of the bubble*/
  --d:35px; /*the distance from the sides*/
  --t:10px; /*the distance from the top*/
  margin:5px;
  border-radius: 50px;
  height:60px;
  background: 
    radial-gradient(var(--h) var(--h) at right,transparent 50%, #065BDB 52%)  0% var(--t)/var(--d) var(--h),
    radial-gradient(var(--h) var(--h) at left,transparent 50%, #065BDB 52%) 100% var(--t)/var(--d) var(--h),
    linear-gradient(to bottom, rgba(87,144,231,1), rgba(87,144,231,0)) 0 var(--t)/100% var(--h),
    #065BDB;
  background-repeat:no-repeat;
  box-sizing:border-box;
}
    <div class="bg"></div>
<div class="bg" style="--h:20px;--d:50px;--t:20px"></div>
<div class="bg" style="--h:40px;--d:100px;--t:5px"></div>