С твоими требованиями я бы использовал SVG.Вот как бы я это сделал:
.star{border:1px solid #d9d9d9; width:30px;}
.star{fill:gold; stroke:orange; stroke-width:5px;}
.star.full use:nth-child(2){display:none;}
.star.half use:nth-child(1),
.star.empty use:nth-child(2)
{display:none;}
.star.empty{fill:none;}
<svg viewBox="0 0 95.1 90.45" style="width:0; height:0; display:none">
<defs>
<polygon id="half_star" points="47.6, 75 18.21, 90.45 23.82, 57.72 0.047, 34.55 32.9, 29.77 47.6, 0"></polygon>
<polygon id="star" points="47.6, 0 62.29, 29.77 95.15, 34.55 71.38, 57.73 76.99, 90.458 47.6, 75 18.21, 90.45 23.82, 57.73 0.05, 34.55 32.9, 29.77"></polygon>
</defs>
</svg>
<svg viewBox="0 0 95.1 90.45" class="star full">
<use xlink:href="#star" />
<use xlink:href="#half_star" />
</svg>
<svg viewBox="0 0 95.1 90.45" class="star half">
<use xlink:href="#star" />
<use xlink:href="#half_star" />
</svg>
<svg viewBox="0 0 95.1 90.45" class="star empty">
<use xlink:href="#star" />
<use xlink:href="#half_star" />
</svg>