<div class="element">
  rgb() function for sRGB
</div>
/* @use postcss-preset-env; */
/* @use postcss-color-function; */

@import url("https://fonts.googleapis.com/css?family=Gochi+Hand");

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  margin: 0;
  padding: 0;
  background-color: #291642;
  font-family: "Gochi Hand", sans-serif;
  color: #fff;
  font-size: 130%;
  letter-spacing: 0.1rem;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  width: 100vw;
  min-height: 100vh;
  padding: 10px;
}

.element {
  width: 50vw;
  min-height: 50vh;
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: 4vh;
  font-size: 2rem;
  
  color: rgb(20% 50% 90%); /* 用百分比的话是0% ~ 100% */
  border: 2vh solid rgb(90% 30% 70% / 65%); /* 增加了透明通道,相当于rgba() */
  box-shadow: 0px 0px 5px 6px rgb(0 220 255); /* 用数字表示的话是0~255 */
  background-color: rgb(90 90 125 / .85); /* 增加了透明通道,相当于rgba() */
}
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