<!-- 

1. From: https://lea.verou.me/2020/10/the-var-space-hack-to-toggle-multiple-values-with-one-custom-property/ 
2. W3C: https://drafts.csswg.org/css-variables/#invalid-variables

-->
<button>Hover Me (^_^)!</button>

<div class="tutorials">
  <a href="https://s.juejin.cn/ds/idkVFyE1/" target="_blank">
    <svg t="1696988571607" class="icon" viewBox="0 0 1024 1024" version="1.1" xmlns="http://www.w3.org/2000/svg" p-id="4422" width="200" height="200">
      <path d="M924.8 576.64v-115.2c12.8-13.44 13.44-26.88 12.8-34.56-3.2-30.08-36.48-42.24-47.36-46.72-79.36-30.08-226.56-89.6-307.84-122.88-49.28-24.32-65.28-19.84-113.28-0.64-12.8 5.12-224.64 83.84-306.56 117.76-44.8 18.56-51.2 46.08-51.2 61.44 0 25.6 17.92 48.64 50.56 62.08L259.84 537.6v257.28l8.32 8.32c3.84 3.84 91.52 92.16 252.16 92.16 150.4 0 236.16-88.96 240-92.8l7.68-8.32V540.16l36.48-15.36-1.28 52.48-29.44 49.28 88.96 84.48 98.56-85.76-36.48-48.64zM710.4 771.2c-22.4 18.56-88.96 67.2-190.08 67.2-111.36 0-179.84-48.64-202.88-67.2V561.28l144.64 58.88h0.64c46.08 17.28 81.28 16 125.44-3.2l122.24-51.84v206.08z m154.24-138.24l-17.92-16.64 13.44-22.4 2.56-102.4c4.48-14.08-0.64-25.6-8.32-32-7.68-7.04-21.76-11.52-36.48-2.56L565.12 563.84c-30.08 13.44-49.92 14.08-81.92 2.56l-298.88-121.6c-7.68-3.2-12.16-6.4-14.08-8.96 1.92-1.92 6.4-5.12 14.72-8.96 81.92-33.92 302.72-116.48 305.28-117.12h0.64c38.4-15.36 38.4-15.36 67.2-0.64l1.92 0.64c80.64 32.64 226.56 92.16 307.2 122.88v163.2l16 21.12-18.56 16z" p-id="4423"></path>
    </svg>
  </a>

</div>
@import url("https://fonts.googleapis.com/css2?family=Exo:wght@600&display=swap");

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

body {
  width: 100vw;
  min-height: 100vh;

  display: flex;
  justify-content: center;
  align-items: center;
  font-family: "Exo", Arial, sans-serif;
  background-color: #151522;

  gap: 10px;
}

button {
  --is-raised: ; /* off by default */
  padding: 1em 1.625em;
  border-radius: 0.2em;
  color: white;
  font: 700 150% / 1 "Exo", Arial, sans-serif;
  cursor: pointer;
  transition: all 0.28s linear;

  border: 1px solid var(--is-raised, rgb(0 0 0 / 0.1));
  background: var(
      --is-raised,
      linear-gradient(hsl(0 0% 100% / 0.3), transparent)
    )
    hsl(200 100% 50%);
  box-shadow: var(
    --is-raised,
    0 1px hsl(0 0% 100% / 0.8) inset,
    0 0.1em 0.1em -0.1em rgb(0 0 0 / 0.2)
  );
  text-shadow: var(--is-raised, 0 -1px 1px rgb(0 0 0 / 0.3));
}

button:hover {
  --is-raised: initial; /* turn on */
}

button:active {
  box-shadow: var(--is-raised, 0 1px 0.2em black inset);
}

.tutorials {
  position: fixed;
  bottom: 1rem;
  right: 1rem;
  z-index: 9999;
  width: 64px;
  aspect-ratio: 1;
  border-radius: 50%;
  background: #3f517e;
  padding: 0.5rem;
  display: grid;
  place-content: center;
  transition: all 0.28s linear;

  &:hover {
    background: #4161b2;
  }

  & svg {
    display: block;
    width: 100%;
    height: 100%;
    filter: invert(1);
  }
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

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