Front-end daily combat: # 6 video demonstrates how to draw a dazzling diamonds sparkling with pure CSS

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https://codepen.io/zhang-ou/pen/qYqwQp

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https://scrimba.com/c/cp24VfV

Source code download

Please download from github.

https://github.com/comehope/front-end-daily-challenges/tree/master/006-blue-dazzling-diamond

Code Reading

Defined dom, comprising a container element:

<div class="diamond">
    <span></span>
</div>

Centered:

html,
body {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

Draw the shape of the first set of facets:

.diamond {
    display: grid;
}

.diamond span {
    border-width: 50px;
    border-style: solid;
}

A first group of facet color, but also to use these color values ​​as the back, so the definition of the variables:

:root {
    --color1: deepskyblue;
    --color2: steelblue;
    --color3: royalblue;
    --color4: dodgerblue;
}

.diamond span {
    border-color: var(--color1) var(--color2) var(--color3) var(--color4);
}

dom container add 3 Group facets:

<div class="diamond">
    <span></span>
    <span></span>
    <span></span>
    <span></span>
</div>

4 the first group of facets composition swastika grid, converted to a diamond shape:

.diamond {
    grid-template-columns: 1fr 1fr;
    transform: rotate(45deg);
}

.diamond span:first-child {
    border-color: transparent var(--color2) var(--color3) transparent;
}

Custom animation effects:

@keyframes animate {
    0% {
        border-color: var(--color1) var(--color2) var(--color3) var(--color4);
    }
    
    25% {
        border-color: var(--color4) var(--color1) var(--color2) var(--color3);
    }
    
    50% {
        border-color: var(--color3) var(--color4) var(--color1) var(--color2);
    }
    
    75% {
        border-color: var(--color2) var(--color3) var(--color4) var(--color1);
    }
    
    100% {
        border-color: var(--color1) var(--color2) var(--color3) var(--color4);
    }
}

Finally, the animation effect applied to the facet except Group 1:

.diamond span:not(:first-child) {
    animation: animate 2s linear infinite;
}

We're done!

Knowledge Point

• variables https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_variables
• border-width https://developer.mozilla.org/en-US/docs/Web/CSS/border-width
• border-color https://developer.mozilla.org/en-US/docs/Web/CSS/border-color
• grid-template-column https://developer.mozilla.org/en-US/docs/Web/CSS/grid-template-columns
• rotate() https://developer.mozilla.org/en-US/docs/Web/CSS/transform-function/rotate