<div class="timer">
  <div class="timer__progress"></div>
  <p class="timer__text">Текст</p>
</div>

body {
  min-height: 100vh;
  margin: 0;
  box-sizing: border-box;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 16px;
  font-family: 'Segoe UI', Arial, Helvetica, sans-serif;
}

.timer {
  --progress: 100;
  
  position: relative;
  width: 200px;
  height: 200px;
  display: flex;
  justify-content: center;
  align-items: center;
  
  &__progress {
    --angle: calc(3.6deg * var(--progress, 0));

    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    background: conic-gradient(#8cd2a2 var(--angle, 0deg), transparent var(--angle, 0deg));
    clip-path: circle(50% at 50%);
  }
  
  &__text {
    margin: 0;
    font-size: 2.5em;
    text-transform: uppercase;
    opacity: 0.75;
    z-index: 1;
  }
}

const timer = document.querySelector('.timer');

const duration = 12000;
let startTime = 0;

const now = () => performance.now();

const update = () => {
  const delta = now() - startTime;
  const difference = duration - delta;
  const percent = Math.max(0, Math.min(100, (difference / duration) * 100));
  
  timer.style.setProperty('--progress', percent);
  
  if (difference > 0) {
    requestAnimationFrame(update);
  }
};

const start = () => {
  startTime = now();
  requestAnimationFrame(update);
};

window.addEventListener('click', start);