html – Unusual line 1px showing up on 3d spin shift dice CSS

 svg {
size: 400px;
elevation: 400px;
}
* {
margin: 0;
cushioning: 0;
history: black;
box-sizing: border-box;
}
. container {
screen: flex;
justify-content: facility;
align-items: facility;
min-height: 100vh;
}
. container.cube-container {
viewpoint: 400px;
screen: flex;
justify-content: facility;
align-items: facility;
flex-direction: column;
}
. container.cube-container. dice {
shift: change 2s ease-in;
transform-style: preserve-3d;
- webkit-transform: translateZ( 0 );
backface-visibility: concealed;
size: 400px;
elevation: 400px;
margin: 50px 0;
}
. container.cube-container. cube.cube1 {
computer animation: horizontal-spin fives ease-in-out;
}
. container.cube-container. cube.cube2 {
computer animation: vertical-spin fives unlimited linear;
}
. container.cube-container. cube.box {
size: 100%;.
elevation: 100%;.
setting: outright;.
screen: flex;.
justify-content: facility;.
align-items: facility;.
}
. container.cube-container. cube.box.front {
history: #ff 66cc;.
change: translateZ( 200px);.
}
. container.cube-container. cube.box.box2.front {
history: #ff 66cc;.
}
. container.cube-container. cube.box.back {
history: #ff 66cc;.
change: translateZ( -200 px) rotateY( 180deg);.
}
. container.cube-container. cube.box.box2.back {
history: #ff 66cc;.
change: translateZ( -200 px) rotateX( -180 deg);.
}
. container.cube-container. cube.box.top {
history: #ff 66cc;.
change: rotateX( -90 deg) translateY( -200 px);.
transform-origin: leading facility;.
}
. container.cube-container. cube.box.box2.top {
history: #ff 66cc;.
change: rotateX( 90deg) translateY( -200 px);.
}
. container.cube-container. cube.box.bottom {
history: #ff 66cc;.
change: rotateX( 90deg) translateY( 200px);.
transform-origin: lower facility;.
}
. container.cube-container. cube.box.box2.bottom {
history: #ff 66cc;.
change: rotateX( -90 deg) translateY( 200px);.
}
. container.cube-container. cube.box.left {
history: #ff 66cc;.
change: rotateY( 270deg) translateX( -200 px);.
transform-origin: facility left;.
}
. container.cube-container. cube.box.box2.left {
history: black;.
}
. container.cube-container. cube.box.right {
history: black;.
change: rotateY( -270 deg) translateX( 200px);.
transform-origin: leading right;.
}
. container.cube-container. cube.box.box2.right {
history: #c 976e0;.
}
@keyframes horizontal-spin {
from {
change: rotateY( 0 );.
}
to {
change: rotateY( 360deg);.
}
}
@keyframes vertical-spin {
from {
change: rotateX( 0 );.
}
to {
change: rotateX( 360deg);.
}
} 

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<> < div course=" cube-container">

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<< div course=" box box1 front"> <> < div course=" span2"><> < svg >>.

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<< div course=" box box1 right">>.

<< div course=" span2"><> < svg >>.

<< photo xlink: href=" https://www.matteogiordano.info/formy-f5.svg" size=" 100%" elevation=" 100%"/>>.

< .

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<< div course=" box box1 left">>.
<< div course=" span2">

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