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HTML

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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="columns">
  <div class="vh">vh</div>
  <div class="lvh">lvh</div>
  <div class="svh">svh</div>
  <div class="dvh">dvh</div>
</div>

<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Expedita, itaque illum eligendi hic tempore assumenda optio, soluta rem repellendus exercitationem deleniti accusantium? Dolores reprehenderit nesciunt saepe quasi alias iure reiciendis laborum quis tempore beatae consectetur sed nemo incidunt excepturi sequi nam cupiditate optio, pariatur doloremque aperiam dicta! Totam ullam perferendis porro tenetur dolor recusandae, reprehenderit fuga dolorum veniam iste architecto vero et hic inventore quasi ipsam commodi dolore dolores consequuntur ab corporis provident ex nemo? Accusamus, maxime ducimus. Eligendi, in. Doloremque maiores corporis, iste earum at aliquam laboriosam sint nostrum obcaecati quasi voluptate dolor dolorem quidem, iusto cupiditate et placeat aperiam sequi nisi corrupti ipsum! Placeat eligendi quos totam molestias porro repellat sed alias soluta dicta ab recusandae reiciendis id doloremque inventore, quo est possimus reprehenderit. Sunt, nostrum est hic deserunt eos voluptatibus eum tempore quaerat earum praesentium, fuga, iure saepe placeat rerum maxime dolorem inventore blanditiis consectetur at corporis odit sed! Saepe optio rem fuga voluptate. Culpa, ducimus a. Fuga nobis porro sunt sit. Aperiam officiis blanditiis vel itaque provident distinctio laborum aspernatur a, tempore, dolore quibusdam, quia quis animi nulla voluptas. Dolorem maiores, porro sint error vitae laudantium consequatur accusamus architecto assumenda quibusdam dolores dicta sunt officia veritatis impedit omnis eius esse distinctio vero consectetur unde provident modi cum. Ex quo odit dolorem numquam delectus dolores maxime at vel quas iusto aut aliquam natus error velit fuga atque ipsam voluptatum eveniet praesentium sapiente, quibusdam fugiat sit nesciunt? Nostrum sapiente unde nisi repellendus nesciunt velit! At in vitae quam ea autem iste quod fuga distinctio commodi natus saepe, totam numquam aperiam laudantium vero fugit, reprehenderit veniam accusamus enim delectus vel. Et nobis, harum quas odit aperiam consequatur, eius doloribus laborum nam sunt iusto distinctio ipsum deserunt reiciendis voluptatibus fugiat voluptates alias animi, accusamus assumenda. Odit nisi nulla ab quae dicta harum neque repudiandae illum maxime quia voluptate adipisci quo, sunt suscipit ipsa, nemo maiores magnam quos, optio vitae amet? Eos sit iste, commodi provident hic at optio ullam inventore nulla, illo, exercitationem voluptate quo saepe molestias dolorem. Nam fugiat assumenda, sint amet nihil, soluta ipsam repellendus natus molestias qui perferendis, est doloremque eum ad reprehenderit cum beatae repellat sunt doloribus? Quae laboriosam ipsum, fugit quaerat consequatur, culpa quas natus nostrum explicabo quibusdam ipsam ipsa, maiores exercitationem nam. Necessitatibus obcaecati, quidem ullam voluptates nobis cum dolores. Tempora quidem temporibus tenetur, sunt, rerum dolor cupiditate esse beatae ex consequuntur iusto, nobis mollitia adipisci odio quia ipsam natus qui vero delectus architecto. Dolore ipsa ea laborum dolor recusandae, impedit culpa soluta, doloribus repellendus aliquid quasi pariatur dicta ducimus maxime fuga, tenetur sunt veniam cumque quod itaque possimus perspiciatis! Inventore expedita aperiam quasi iste porro aliquid nam accusamus harum eius vel, praesentium quisquam dolore molestias ad itaque ipsam, vero ducimus! Vitae aperiam vero porro totam molestiae sunt laborum inventore non, consequuntur recusandae sequi, facilis explicabo fugit maiores ut nesciunt suscipit fuga voluptatibus laboriosam rem sapiente. Saepe quia molestiae adipisci numquam temporibus, voluptates soluta porro rem iure voluptas error, quaerat commodi dolorum placeat autem unde recusandae incidunt cumque, qui maxime! Consequuntur, numquam molestias. Esse beatae, ducimus eos temporibus laborum tempora consequuntur consequatur libero autem. Consectetur beatae, inventore quas assumenda rem sit ea sequi. Deleniti reprehenderit sunt, quos aperiam ratione ex ad enim molestias, veniam esse numquam laborum illo accusamus et praesentium cumque nemo temporibus quas. Tenetur, deleniti pariatur sequi laudantium, quis sint, impedit praesentium in quidem asperiores quod placeat. Voluptatibus eaque error enim laboriosam ipsum ducimus eligendi fuga neque veritatis eos quibusdam dolores recusandae necessitatibus, quam fugiat dolore voluptatum porro, beatae ullam. Natus corrupti dolores asperiores maxime enim deserunt sint eaque nihil dolorem inventore nostrum vero consequuntur possimus repudiandae, quod a! Officiis a et, facilis velit consequuntur excepturi numquam sunt ipsam deserunt deleniti molestias harum repellat placeat, quo voluptatem pariatur eum aliquid corrupti voluptates! At dicta repellat nisi iste commodi consequatur quae delectus temporibus ut dolorem iusto nulla tempora labore molestiae tempore, in architecto sed magnam aliquid distinctio animi tenetur deserunt dolor? Quam, consequatur animi omnis incidunt voluptatibus similique vero excepturi! Molestiae dolores in accusamus quidem hic illo saepe consequuntur quo. Esse nulla in assumenda adipisci, nemo rem, accusamus eveniet delectus impedit repellendus ex nihil ducimus officiis libero consequuntur et veritatis illo quis nam provident dicta! Saepe pariatur illum fugit tempore, tempora, dolor quo, animi et eum perspiciatis reiciendis ex ut ad autem? Vel voluptate ipsam, nemo expedita harum minima a distinctio corporis quos tenetur voluptatem ducimus eos rem iste commodi. Consectetur, hic facere. Dolor rem facere nisi atque qui ex ipsa, iure necessitatibus rerum suscipit tenetur nobis vel pariatur dolorem at voluptas a, doloribus reprehenderit quae optio sapiente! Asperiores obcaecati quisquam reprehenderit ex eveniet distinctio mollitia quasi adipisci eligendi blanditiis facilis consequuntur nisi nobis omnis, sit, suscipit soluta perspiciatis nulla tempore necessitatibus inventore! Consequuntur facilis praesentium voluptate corporis quaerat incidunt sit neque distinctio maiores. Esse, saepe consequuntur ex, molestiae inventore atque, reiciendis incidunt illo autem doloremque quo itaque quidem qui voluptates veniam! Provident natus atque sed libero nobis iste nostrum, vero culpa non, maxime facere dolores aut. Repellat corrupti veritatis ipsum. Eos, beatae unde. Nobis minima dolores repellat, voluptatibus debitis provident voluptate qui facere vero. Cupiditate labore in dignissimos voluptate hic porro quod ratione repellat perferendis ab atque error maiores molestias, dolores officiis? Repellat, tempora. Rerum a mollitia sint iste? Beatae ab ea, ex eos autem doloremque tenetur. Distinctio, adipisci? Expedita incidunt doloremque aspernatur vel voluptatibus. Velit corporis perferendis illum exercitationem, suscipit magnam amet ullam sunt eos doloremque cupiditate commodi totam natus accusantium mollitia excepturi asperiores! Obcaecati pariatur cum numquam dicta harum error, sit ut incidunt sunt atque quibusdam officia a consectetur accusamus odit possimus impedit saepe. Unde ratione quam officiis ex ullam nemo recusandae dolorem eum temporibus praesentium vel, odit magni, voluptatem, ipsam laudantium eligendi placeat deserunt atque non? Ea consectetur eaque, incidunt excepturi molestias dolorum fuga distinctio rerum amet, sed repellat culpa porro quas quis, laboriosam vel odit doloremque quia unde. Modi tenetur est, ipsam repellendus corporis, unde neque sunt earum, minima fuga exercitationem magnam. Iusto minus incidunt quod voluptatum commodi.</p>
!

CSS 

              
                .columns {
  display: flex;
  position: fixed;
  inset: 0;
}

:where(.columns) div {
  background: hwb(10 0% 0% / 0.95);
  flex-grow: 1;
  border: 1rem solid rgb(255 255 255 / 0.95);
  outline: 1px solid #000;
  padding-top: 1rem;
  height: 100vh;
}


.lvh {
  background: hwb(260 0% 0% / 0.95);
  height: 100lvh;
}

.svh {
  background: hwb(140 0% 0% / 0.95);
  height: 100svh;
}

.dvh {
  background: hwb(300 0% 0% / 0.95);
  height: 100dvh;
}

body {
  margin: 0;
  font-size: 1.6rem;
  font-family: sans-serif;
  text-align: center;
  font-weight: bold;
}

* {
  box-sizing: border-box;
}
!

JS
!
999px

Console