纯 CSS 倒计时动画

Question

我正在尝试制作纯 HTML/CSS 倒计时动画，但我正在努力使其顺利运行。现在我只介绍分钟和秒。请注意，我使用animation-delay 属性将倒计时重置为某个初始时间。

目前一切正常，除了与 x10 分钟对应的数字未与其余数字同步变化。 接下来我将粘贴我的代码和两个代码笔，第一个正常版本具有正常行为的正确时间，另一个快 10 倍，以便您快速了解问题。

• https://codepen.io/ecazorla/pen/WKdZpQ（普通版）
• https://codepen.io/ecazorla/pen/bjapeN（快 10 倍的版本）

@keyframes tick6 {
        0%      { margin-top: 0; }
        16%     { margin-top: -2rem;  }
        33%     { margin-top: -4rem;  }
        50%     { margin-top: -6rem;  }
        66%     { margin-top: -8rem;  }
        83%     { margin-top: -10rem;  }
        100%    { margin-top: -12rem;  }
    }

    @keyframes tick10 {
        0%      { margin-top: 0; }
        10%     { margin-top: -2rem;  }
        20%     { margin-top: -4rem;  }
        30%     { margin-top: -6rem;  }
        40%     { margin-top: -8rem;  }
        50%     { margin-top: -10rem;  }
        60%     { margin-top: -12rem;  }
        70%     { margin-top: -14rem;  }
        80%     { margin-top: -16rem;  }
        90%     { margin-top: -18rem;  }
        100%    { margin-top: -20rem;  }
    }
    
body {
  background-color: black;
}

.container {
  background-color: white;
}

.digit {
  display: inline-block;
  height: 2rem;
  overflow: hidden;
  width: 1ch;
}

.digit span {
  display: block;
  height: 2rem;
  width: 100%;
}

.minutes-digit-one {
  animation: tick6 3600s step-end;
  animation-iteration-count: infinite;
  animation-delay: -540s;
}

.minutes-digit-two {
  animation: tick10 600s step-end;
  animation-iteration-count: infinite;
  animation-delay: -540s;
}

.seconds-digit-one {
  animation: tick6 60s step-end;
  animation-iteration-count: infinite;
  animation-delay: -540s;
}

.seconds-digit-two {
  animation: tick10 10s;
  animation-iteration-count: infinite;
  animation-delay: -540s;
}

<div class="container">
  <div class="digit">
    <span class="minutes-digit-one">5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>5</span>
  </div>
  <div class="digit">
    <span class="minutes-digit-two">9</span>
    <span>8</span>
    <span>7</span>
    <span>6</span>
    <span>5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>9</span>
  </div>
  <div class="digit">
    <span>:</span>
  </div>
  <div class="digit">
    <span class="seconds-digit-one">5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>5</span>
  </div>
  <div class="digit">
    <span class="seconds-digit-two">9</span>
    <span>8</span>
    <span>7</span>
    <span>6</span>
    <span>5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>9</span>
  </div>
</div>

Answer 1

这是由于关键帧的百分比值。您使用的是16%，而应该是16.6667% (100/6) 更准确和准确，与其他值相同。

当使用360s 或3600s 作为持续时间时，16% 和16.6667% 之间会有明显的区别，因此状态会更早发生变化，您将遇到同步问题。使用6s 作为秒数时，您可能不会注意到这一点。

@keyframes tick6 {  
    0%          { margin-top: 0; }      /* 0*(100/6) */
    16.6667%    { margin-top: -2rem;  } /* 1*(100/6) */
    33.3333%    { margin-top: -4rem;  } /* 2*(100/6) */
    50%         { margin-top: -6rem;  } /* 3*(100/6) */
    66.6667%    { margin-top: -8rem;  } /* 4*(100/6) */
    83.3333%    { margin-top: -10rem; } /* 5*(100/6) */
    100%        { margin-top: -12rem; } /* 6*(100/6) */
}

@keyframes tick10 {
    0%      { margin-top: 0; }
    10%     { margin-top: -2rem;  }
    20%     { margin-top: -4rem;  }
    30%     { margin-top: -6rem;  }
    40%     { margin-top: -8rem;  }
    50%     { margin-top: -10rem;  }
    60%     { margin-top: -12rem;  }
    70%     { margin-top: -14rem;  }
    80%     { margin-top: -16rem;  }
    90%     { margin-top: -18rem;  }
    100%    { margin-top: -20rem;  }
}

body {
  background-color: black;
}

.container {
  background-color: white;
}

.digit {
  display: inline-block;
  height: 2rem;
  overflow: hidden;
  width: 1ch;
}

.digit span {
  display: block;
  height: 2rem;
  width: 100%;
}

.minutes-digit-one {
  animation: tick6 360s infinite step-end;
  /*animation-delay: -54s;*/
}

.minutes-digit-two {
  animation: tick10 60s infinite step-end;
  /*animation-delay: -54s;*/
}

.seconds-digit-one {
  animation: tick6 6s infinite step-end;
  /*animation-delay: -54s;*/
}

.seconds-digit-two {
  animation: tick10 1s infinite step-end;
}

<div class="container">
  <div class="digit">
    <span class="minutes-digit-one">5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>5</span>
  </div>
  <div class="digit">
    <span class="minutes-digit-two">9</span>
    <span>8</span>
    <span>7</span>
    <span>6</span>
    <span>5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>9</span>
  </div>
  <div class="digit">
    <span>:</span>
  </div>
  <div class="digit">
    <span class="seconds-digit-one">5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>5</span>
  </div>
  <div class="digit">
    <span class="seconds-digit-two">9</span>
    <span>8</span>
    <span>7</span>
    <span>6</span>
    <span>5</span>
    <span>4</span>
    <span>3</span>
    <span>2</span>
    <span>1</span>
    <span>0</span>
    <span>9</span>
  </div>
</div>