CSS 데모: -webkit-text-stroke-width 데모 버튼을 클릭해 보세요!
selector {
    -webkit-text-stroke-width: /* value */
}
/* 키워드 값 */
-webkit-text-stroke-width: thin;
-webkit-text-stroke-width: medium;
-webkit-text-stroke-width: thick;

/* 길이 값 */
-webkit-text-stroke-width: 4px;
-webkit-text-stroke-width: 0.15em;
-webkit-text-stroke-width: 3mm;
-webkit-text-stroke-width: 6pt;

/* width: % 단위 적용 불가 */
-webkit-text-stroke-width: 5%;

/* 글로벌 값 */
-webkit-text-stroke-width: inherit;
-webkit-text-stroke-width: initial;
-webkit-text-stroke-width: revert;
-webkit-text-stroke-width: revert-layer;
-webkit-text-stroke-width: unset;
<style>
    .text {
        font-size: 70px;
        font-weight: 900;
        color: white;
        -webkit-text-stroke-color: red;
        -webkit-text-stroke-width: 1px;
    }
</style>
<p class="text">텍스트</p>
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