rgin-top: 0; }
    .ref { background-color: rgb(27.888% 38.072% 89.414%); width: 12em; height: 6em; margin-bottom: 0; } /* oklab(55% 0 -0.2) converted to sRGB */
    .test { background-color: oklab(55% 0 -0.2); }
</style>
<body>
    <p>Test passes if you see a single square, and not two rectangles of different colors.</p>
    <div class="ref"></div>
    <div class="test"></div>
</body>
