/* Valeurs avec un mot-clé */
font-weight: normal;
font-weight: bold;
/* Valeurs relatives à l'élément parent */
font-weight: lighter;
font-weight: bolder;
/* Valeurs numériques */
font-weight: 1;
font-weight: 100;
font-weight: 100.6;
font-weight: 123;
font-weight: 200;
font-weight: 300;
font-weight: 321;
font-weight: 400;
font-weight: 500;
font-weight: 600;
font-weight: 700;
font-weight: 800;
font-weight: 900;
font-weight: 1000;
/* Valeurs globales */
font-weight: inherit;
font-weight: initial;
font-weight: unset;
p {
font-weight: normal;
}
a {
font-weight: bold;
}
p.thick {
font-weight: 780;
}
<p style="font-weight:normal;">font-weight: normal</p>
<p style="font-weight:bold;">font-weight: bold</p>
<p style="font-weight:bolder;">font-weight: bolder</p>
<p style="font-weight:lighter;">font-weight: lighter</p>
<p style="font-weight:100;">font-weight: 100</p>
<p style="font-weight:200;">font-weight: 200</p>
<p style="font-weight:300;">font-weight: 300</p>
<p style="font-weight:400;">font-weight: 400</p>
<p style="font-weight:500;">font-weight: 500</p>
<p style="font-weight:600;">font-weight: 600</p>
<p style="font-weight:700;">font-weight: 700</p>
<p style="font-weight:800;">font-weight: 800</p>
<p style="font-weight:900;">font-weight: 900</p>
p{
font-weight: bold;
}
/* Keyword values */
font-weight: normal;
font-weight: bold;
/* Keyword values relative to the parent */
font-weight: lighter;
font-weight: bolder;
/* Numeric keyword values */
font-weight: 100;
font-weight: 200;
font-weight: 300;
font-weight: 400; /* normal */
font-weight: 500;
font-weight: 600;
font-weight: 700; /* bold */
font-weight: 800;
font-weight: 900;
If one does not work try another: css "fontweight" "font-weight" "fontWeight"