I'm trying to create an animation like the one in this gif :

Here is my HTML/SVG/CSS :
<!DOCTYPE html>
<html>
<head>
<title>svg animation logo</title>
<style>
path,
line,
circle {
fill: none;
stroke: #164a07;
stroke-width: 4;
}
svg {
background: #9bc345;
}
</style>
</head>
<body>
<svg width="180" height="180" version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g id="squars">
<path id="sq3" d="m 55.693069,108.71287 20.940594,0.44555 0.891089,21.38613 -21.831683,-0.44554 z"/>
<path id="sq2" d="m 54.56835,75.965348 20.940594,0.44555 0.891089,21.386127 -21.831683,-0.44554 z"/>
<path id="sq1" d="m 55.459439,43.886141 20.940594,0.44555 0.891089,21.386127 -21.831683,-0.44554 z"/>
</g>
<g id="ticks">
<path id="tick1" d="m 60.136501,49.945523 6.237623,7.79703 c 0,0 6.014852,-16.930694 12.252476,-16.707921 6.237623,0.222772 -0.222773,0.222772 -0.222773,0.222772"/>
<path id="tick2" d="m 60.816832,82.871287 6.237623,7.79703 c 0,0 6.014852,-16.930694 12.252476,-16.707921 6.237623,0.222772 -0.222773,0.222772 -0.222773,0.222772"/>
<path id="tick3" d="m 60.359273,115.2178 6.237623,7.79703 c 0,0 6.014852,-16.93069 12.252476,-16.70792 6.237623,0.22277 -0.222773,0.22277 -0.222773,0.22277"/>
</body>
</html>
I can hide the checkmarks with a mask :
<defs>
<mask id="mmm">
<rect width="180" height="50" x="0" y="92" fill="black" />
<rect width="180" height="98" x="0" y="0" fill="white" />
</mask>
</defs>
But I can't figure out how to have them animate in. I think that I need to use <animateTransform attributeName="transform" but I don't really understand how to do it. Can someone please help me with this?