.effective{
fill:red;
}
.effective:hover{
fill:black;
transition: fill 2s ease-in;
}
<svg width="210mm" height="450mm" viewBox="0 0 744.09449 159.44881">
<path d="m 18.929688,529.44141 c 1.140051,2.17164 1.739409,4.60197 1.74414,7.07226 -0.0033,2.41521 -0.575072,4.79339 -1.666016,6.92969 l 36.876954,0 c 17.101683,0 11.124297,14.78094 13.525192,34.92207 7.304679,27.32129 35.935342,38.13518 62.612922,41.73111 -1.5457,-2.42739 -4.33484,-7.94712 -4.33733,-10.8524 0.005,-3.11453 0.90166,-5.74434 2.66254,-8.27277 -23.30774,-1.1068 -29.8766,-7.34118 -39.33413,-22.29658 -4.829034,-11.35821 5.68082,-49.23338 -28.703413,-49.23338 z" transform="translate(0.5714286,1.42857)" class="effective" />
</svg>