How did you create the GIF, I see the code and it outputs only one image... did you use Wolfram too to export a GIF consisting of 8 evaluations of that cell?

Yes, that will do it. For example, here's code that will do the whole thing (notice that I'm creating a $540 \times 540$ GIF, whereas the code in the original post creates a single $1080 \times 1080$ image):

RandomAngle[] := RandomVariate[UniformDistribution[{0, 2 Pi}]];
RandomDirection[] := 
  With[{\[Theta] = RandomAngle[]}, {Cos[\[Theta]], Sin[\[Theta]]}];

img = Block[{r, \[Theta], v, p, 
   cols = RGBColor /@ {"#252A34", "#FF2E63", "#08D9D6", "#EAEAEA"}},
  Table[
   Graphics[{Thickness[.0002], 
     Table[{r = RandomVariate[UniformDistribution[]];
       \[Theta] = RandomAngle[];
       v = RandomDirection[];
       p = {r Cos[\[Theta]], r Sin[\[Theta]]};
       {Blend[cols, r], InfiniteLine[p, v]}}, {20000}]}, 
    PlotRange -> 1, ImageSize -> 540],
   {8}]
  ];

Export["animation.gif", img, "DisplayDurations" -> 1/25, 
 "AnimationRepetitions" -> Infinity]

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