<template>
  <div class="tabs">
    <figure v-for="tab in tabs" 
            :key="tab.id"
            class="tab"
            :class="getTabClass(tab.id)">
      <nav class="tab__header">
        <button class="tab__button"
                @click="selectTabById(tab.id)">
          <span class="bar"
                v-for="i in (tab.id + 1)"></span>
        </button>
      </nav>
      <article class="tab__content">
        <div class="skeleton"
             v-for="content in tab.content"
             v-bind:style="{ width: content.width + '%' }"></div>
      </article>
    </figure>
  </div>
</template>

<script>
const TABS_AMOUNT = 3;
const CONTENT = Array.from({ length: TABS_AMOUNT },
  () => Array.from(
    { length: 4 }, 
    () => ({ width: 70 + Math.random() * 20 })
  )
);

export default {
  data() {
    return {
      tabs: CONTENT.map((content, id) => ({
        id,
        content
      })),
      currentTabIndex: 0,
      prevTabIndex: 2
    };
  },
  methods: {
    getTabClass(id) {
      return [{
        'tab--current': this.currentTabIndex === id,
        'tab--prev': this.prevTabIndex === id
      }];
    },
    selectTabById(id) {
      if (id === this.currentTabIndex) { return; }
      this.prevTabIndex = this.currentTabIndex;
      this.currentTabIndex = id;
    }
  },
};
</script>

<style>
  *,
  ::before,
  ::after {
    box-sizing: border-box;
  }

  html,
  body {
    width: 100%;
    height: 100%;
  }
  
  html {
    --color-light: #665e68;
    --color-regular: #353637;
    --color-semidark: #9f946f;
    --color-dark: #bfb48f;
    --color-accent: #f2efe9;
    --color-background: #564e58;
    --color-background-a: #200e15;
    --color-background-b: #151617;
    
    font-family: Arial, sans-serif;
    display: flex;
    background:
      linear-gradient(
        to bottom,
        var(--color-background-b),
        var(--color-background-a)
      );
    overflow: hidden;
  }

  body {
    color: var(--color-regular);
    margin: 0;
    flex: 1;
    display: flex;
    flex-flow: column;
    align-items: center;
    justify-content: center;
  }
  
  .tabs {
    min-width: 400px;
    max-width: 100%;
    position: relative;
    perspective: 1000px;
    height: 300px;
  }

  .tab {
    position: absolute;
    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
    margin: 0;
    pointer-events: none;
    display: flex;
    flex-flow: column;
    z-index: 0;
    animation: swipe 1200ms ease;
    
    --border-radius: 12px;
    --border-radius-small: calc(var(--border-radius) / 4);
  }

  .tab__header {
    background: transparent;
    display: flex;
    height: calc(3em + var(--border-radius-small));
    margin-bottom: calc(0px - var(--border-radius-small));
    padding: 0 var(--border-radius-small);
  }

  .tab__button {
    position: relative;
    pointer-events: all;
    cursor: pointer;
    font: inherit;
    outline: none;
    border: 0;
    color: var(--color-light);
    background: var(--color-semidark);
    width: 32.5%;
    font-weight: 600;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
    transition: all 160ms ease;
  }
  
  .tab__button:hover {
    background: var(--color-dark);
  }
  
  .tab.tab--current {
    animation: none;
    z-index: 1;
  }
  
  .tab.tab--current .tab__content,
  .tab.tab--current .tab__button,
  .tab.tab--prev .tab__content,
  .tab.tab--prev .tab__button {
    box-shadow: 0 6px 16px 0 rgba(0, 0, 0, 0.36);
  }
  
  .tab.tab--prev {
    z-index: -1;
  }
  
  .tab.tab--current .tab__button {
    color: var(--color-regular);
    background: var(--color-accent);
  }
  
  .tab:nth-child(1) .tab__button {
    justify-self: flex-start;
    margin: 0 auto 0 0;
  }
  
  .tab:nth-child(2) .tab__button {
    justify-self: center;
    margin: 0 auto;
  }
  
  .tab:nth-child(3) .tab__button {
    justify-self: flex-end;
    margin: 0 0 0 auto;
  }

  .tab__content {
    text-align: justify;
    font-size: 1.5em;
    line-height: 1.25;
    flex: 1;
    transform-style: preserve-3d;
    pointer-events: all;
    background: var(--color-accent);
    padding: 1.5em 2em;
    border-radius: 
      var(--border-radius-small) 
      var(--border-radius-small)
      var(--border-radius) 
      var(--border-radius);
  }
  
  .skeleton {
    width: 100%;
    height: 1em;
    border-radius: --border-radius-small;
    background: var(--color-dark);
  }
  
  .skeleton + .skeleton {
    margin-top: 0.5em;
  }
  
  .bar {
    display: inline-block;
    width: 0.5em;
    height: 0.5em;
    margin: 0 0.1em;
    border-radius: --border-radius-small;
    background: var(--color-background);
    transition: all 260ms ease;
  }
  
  .tab--current .bar {
    background: var(--color-dark);
  }
  
  @keyframes swipe {
    0% {
      transform: translate3d(0, 0, 0);
      z-index: 2;
    }
    50% {
      transform: translate3d(80%, 0, 100px) rotate3d(0, 1, 0, -80deg);
      z-index: 2;
    }
    51% { z-index: -1; }
    100% {
      transform: translate3d(0, 0, 0);
    }
  }
  
  @media only screen and (max-width: 400px) {
    .tabs {
      min-width: 100%;
    }
  }
</style>

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.