<section>
  <div class="container">
    <h1>CSS is Awesome</h1>
    <h1>CSS is Awesome with fit-content()</h1>
    <h1>CSS is Awesome</h1>
  </div>
  <form action="">
    <input type="range" min="0" max="100" value="100" />
  </form>
</section>

<form action="">
  <span>grid-template-columns:</span>
  <label for="case1">
    <input type="radio" name="grid-template-columns" value="1fr 1fr 1fr" id="case1" checked />
    1fr 1fr 1fr
  </label>

  <label for="case2">
    <input type="radio" name="grid-template-columns" value="1fr fit-content 1fr" id="case2" />
    1fr fit-content 1fr
  </label>

  <label for="case3">
    <input type="radio" name="grid-template-columns" value="1fr fit-content(200px) 1fr" id="case3" />
    1fr fit-content(200px) 1fr
  </label>

  <label for="case4">
    <input type="radio" name="grid-template-columns" value="1fr fit-content(20vw) 1fr" id="case4" />
    1fr fit-content(20vw) 1fr
  </label>

  <label for="case5">
    <input type="radio" name="grid-template-columns" value="1fr 1fr fit-content(50%) 1fr" id="case5" />
    1fr fit-content(50%) 1fr
  </label>

  <label for="case6">
    <input type="radio" name="grid-template-columns" value="1fr 1fr fit-content(2fr) 1fr" id="case6" />
    1fr fit-content(2fr) 1fr
  </label>

  <label for="case7">
    <input type="radio" name="grid-template-columns" value="1fr 1fr fit-content() 1fr" id="case7" />
    1fr fit-content() 1fr
  </label>
</form>

<div id="output">
  <label>网格轨道计算值:</label>
  <span></span> | <span></span> | <span></span>
</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;
  flex-direction: column;
  gap: 20px;
  font-family: "Exo", Arial, sans-serif;
  background-color: #f7f7f7;

  padding: 20px;
}

section {
  min-width: 60vw;
  margin: 0 auto;

  display: flex;
  justify-content: center;
  /*   align-items: center; */
  flex-direction: column;

  gap: 10px;
  box-shadow: 0 0 0 6px rgb(0 0 0 / 13%);
  border-radius: 6px;
}

.container {
  border: 1px dashed #f36;
  border-radius: 1px;
}

h1 {
  background-color: #f7f7f7;
  place-self: center stretch;
  color: #444;
  padding: 5px 0;
  position: relative;
}

h1:nth-child(1) {
  background-color: #f1c2c6;
}

h1:nth-child(2) {
  background-color: #dac2f1;
}

h1:nth-child(3) {
  background-color: #ccf1c2;
}

h1:nth-child(4) {
  background-color: #00bcd4;
}

form {
  width: 100%;
}
input[type="range"] {
  width: 100%;
}
.container {
  --width: 100%;
  --grid-template-columns: 1fr 1fr 1fr;
  padding: 20px;
  width: var(--width);
  gap: 10px;
  display: grid;
  grid-template-columns: var(--grid-template-columns);
}

section + form {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(20ch, 1fr));
  gap: 15px;
  max-width: 80vw;
  margin: 0 auto;
}

form > span {
  grid-row: span 4;
  place-self: center;
}

form > label {
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

#output {
  text-align: center;
}
const range = document.querySelector('input[type="range"]');
const container = document.querySelector(".container");
const radios = document.querySelectorAll('input[type="radio"]');
const outputVals = document.querySelectorAll("#output > span");
const gridItems = document.querySelectorAll(".container > h1");

range.addEventListener("input", (etv) => {
  container.style.setProperty("--width", `${etv.target.value}%`);
});
console.log(outputVals[0]);

outputVals.forEach((output, index) => {
  output.textContent = getComputedStyle(gridItems[index]).width;
});

radios.forEach((radio, index) => {
  radio.addEventListener("click", (etv) => {
    container.style.setProperty("--grid-template-columns", etv.target.value);

    outputVals.forEach((output, index) => {
      output.textContent = getComputedStyle(gridItems[index]).width;
    });
  });
});
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