Pure CSS Continuous Horizontal Text Scroll Without Break

Solution 1:

You could try having two marquees and set one of them with a delayed animation of 2.5s which is half the time of the full animation (5s).

.marquee {
  margin: 0 auto;
  white-space: nowrap;
  overflow: hidden;
  position: absolute;
}

.marquee span {
  display: inline-block;
  padding-left: 100%;
  animation: marquee 5s linear infinite;
}

.marquee2 span {
  animation-delay: 2.5s;
}

@keyframes marquee {
  0% {
    transform: translate(0, 0);
  }
  100% {
    transform: translate(-100%, 0);
  }
}
<p class="marquee">
  <span>This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text -&nbsp;</span>
</p>
<p class="marquee marquee2">
  <span>This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text - This is text -&nbsp;</span>
</p>

Solution 2:

This is similar to above answer. I have taken it from the official website of Next.js. They have used this with SVGs to make a slider to show which popular companies are using their framework.

.wrapper {
  max-width: 100%;
  overflow: hidden;
}

.marquee {
  white-space: nowrap;
  overflow: hidden;
  display: inline-block;
  animation: marquee 10s linear infinite;
}

.marquee p {
  display: inline-block;
}

@keyframes marquee {
  0% {
    transform: translate3d(0, 0, 0);
  }
  100% {
    transform: translate3d(-50%, 0, 0);
  }
}
<div class="wrapper">
  <div class="marquee">
    <p>
      Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce volutpat, ante eu bibendum tincidunt, sem lacus vehicula augue, ut suscipit.
    </p>
    <p>
      Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce volutpat, ante eu bibendum tincidunt, sem lacus vehicula augue, ut suscipit.
    </p>
  </div>
</div>