Разработка Ротация контента на боковой панели

@import url('https://fonts.googleapis.com/css?family=Roboto+Condensed:300,400|Roboto:300,400,500');

$body-bg: #20262e;
$bg-dark: darken($body-bg, 10%);
$bg-light: lighten($body-bg, 10%);
$bg-over-light: lighten($body-bg, 15%);
$bg-super-light: lighten($body-bg, 35%);
$font: 'Roboto';
$text: lighten($body-bg, 60%);
$akcentColor: #3266d5;
$shadow: 0px 7px 16px 0px rgba(41,53,108,0.25);

html, body, div, span, applet, object, iframe, h1, h2, h3, h4, h5, h6, p, blockquote, pre, a, abbr, acronym, address, big, cite, code, del, dfn, em, img, ins, kbd, q, s, samp, small, strike, strong, sub, sup, tt, var, b, u, i, center, dl, dt, dd, ol, ul, li, fieldset, form, label, legend, table, caption, tbody, tfoot, thead, tr, th, td, article, aside, canvas, details, embed, figure, figcaption, footer, header, hgroup, menu, nav, output, ruby, section, summary, time, mark, audio, video {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 100%;
  font: inherit;
  vertical-align: baseline;
}

html {
  box-sizing: border-box;
  scroll-behavior: smooth;
  overflow-x: hidden !important;
}

*,*::before,*::after {
  box-sizing: inherit;
}

html, body {
  height: 100%;
}

body {
  position: relative;   
  // display: flex;
  // flex-direction: column;
  // justify-content: flex-start;
  // align-items: flex-start; 
  font-family: $font,'-apple-system', BlinkMacSystemFont, Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.467;
  font-weight: 300;
  letter-spacing: -.01em;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  color: $text; 
  background: radial-gradient(ellipse at center, $body-bg 0%, $bg-dark 80%) fixed;
}

::-webkit-scrollbar {
  width: 1rem;
  -webkit-transition: .3s background;
  transition: .3s background;
}
::-webkit-scrollbar-track {
  box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.85);
  background: $bg-dark;
}
::-webkit-scrollbar-thumb {
  border-radius: 1rem;
  background: $bg-over-light;
  box-shadow: inset 0 0 0.5rem rgba(0, 0, 0, 0.5);
}
:hover::-webkit-scrollbar-thumb {
  background: $bg-light;
}

[tabindex="-1"]:focus {
  outline: 0 !important;
}

hr {
  box-sizing: content-box;
  height: 0;
  overflow: visible;
}

h1, h2, h3, h4, h5, h6 {
  font-family: Oswald;
  font-weight: 500;
  margin-top: 0;
  margin-bottom: 0.5rem;
}

h1 {
  font-size: 2.625rem;
  line-height: 1.2;
}
h2 {
  font-size: 2rem;
  line-height: 1.3;
}
h3 {
  font-size: 1.5rem;
  line-height: 1.4;
}
h4 {
  font-size: 1.25rem;
  line-height: 1.4;
}
h5 {
  font-size: 16px;
  line-height: 1.4;
}
h6 {
  font-size: 0.875rem;
  line-height: 1.4;
}

* + h1,
* + h2,
* + h3,
* + h4,
* + h5,
* + h6, {
  margin-top: 24px;
}

p {
  margin-top: 0;
  margin-bottom: 1rem;
}

a {
  color: inherit;
  text-decoration: none;
}

.underline-animation {
  display: inline-block;
  position: relative;
 
  &::after {
    content: '';
    position: absolute;
    width: 100%;
    transform: scaleX(0);
    height: 1px;
    bottom: 0;
    left: 0;
    background-color: #fff;
    transform-origin: bottom right;
    transition: transform 0.25s ease-out;
  }
  &:hover::after {
    transform: scaleX(1);
    transform-origin: bottom left;
  }
}

// button {
//   padding: 0;
//   border: none;
//   font: inherit;
//   color: inherit;
//   background-color: transparent;
//   cursor: pointer;
// }

.btn {
  /* default for <button>, but needed for <a> */
  display: inline-block;
  text-align: center;
  text-decoration: none;

  /* create a small space when buttons wrap on 2 lines */
  margin: 2px 0;

  /* invisible border (will be colored on hover/focus) */
  border: solid 1px transparent;
  border-radius: 4px;

  /* button size comes from text + padding, avoid height */
  padding: 0.5em 1em;
  font-size: 0.875em;
  /* make sure colors have enough contrast! */
  color: #FFFFFF;
  background-color: $akcentColor;
  transition: all 0.2s ease-in-out;
 
  /* old-school "down" effect on clic + color tweak */
  &:active {
    transform: translateY(1px);
    filter: saturate(150%);
  }

  /* inverse colors on hover */
  &:hover {
    color: $akcentColor;
    border-color: currentColor;
    background-color: transparent;
  }

  /* Firefox: remove the inner border shown on focus */
  &::-moz-focus-inner {
    border: none;
  }

  /* make sure we have a visible focus ring */
  &:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba($akcentColor, 0.5),
                0 0 0 1.5px rgba($akcentColor, 0.5);
  }
 
  /* hide focus style if not from keyboard navigation */
  &:focus:not(.focus-visible) {
    box-shadow: none;
  }
}

.ripple {
  background-position: center;
  transition: background 0.8s;
}
.ripple:hover {
  background: #47a7f5 radial-gradient(circle, transparent 1%, #47a7f5 1%) center/15000%;
}
.ripple:active {
  background-color: #6eb9f7;
  background-size: 100%;
  transition: background 0s;
}

/* Button style */
button {
  border: none;
  border-radius: 2px;
  padding: 1em 1.5em;
  //font-size: 16px;
  text-transform: uppercase;
  cursor: pointer;
  color: #fff;
  background-color: $bg-light;
  box-shadow: 0 0 4px #999;
  outline: none;
}


input[type="text"],
input[type="number"],
select,
textarea {
  font-size: 16px;
}

.img-wrapper {
  position: relative;
  width: 100%;
  padding-top: 75%; // for 4:3, 56.25% for 16:9
  overflow: hidden;
 
  img {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    object-fit: cover;
    object-position: center;
  }
}

// scroll-block

.wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
}

.scroll-list {
  position: relative;
  width: 100%;
  max-width: 700px;
  padding: 24px;
  //margin: 48px auto 0;

  @media screen and (max-width: 768px) {
    margin-top: 24px
  }
 
  h3 {
    position: absolute;
    left: 48px; top: 48px;
    max-width: 600px;
    z-index: 3;
  }
 
  &__wrp {
    width: 100%;
    height: 90vh;
    overflow: auto;
    padding: 1rem;
    box-shadow: 0px 7px 46px 0px rgba(41, 53, 108, 0.45);
    //background-color: #252529;
    margin-bottom: 15px;
    border-radius: 8px;     
    
      .scrollbar-track {
        display: none !important;
      }

      @media screen and (max-width: 768px) {
        padding: 12px;
      }

  }

  &__item {
    position: relative;
    display: flex;
    justify-content: space-between;
    align-items: stretch;
    width: 100%;   
    height: auto;
    padding: 1em;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.7);   
    margin-bottom: 1rem;
    //cursor: pointer;
    transition: all .35s ease-in-out;
    opacity: 0;
    transform: scale(0.75);
    //box-shadow: $shadow;   
    
    &::after {
      position: absolute;
      left: 0;
      top: 0;
      content: "";
      display: block;
      width: 100%;
      height: 1px;     
      background-color: #fff;
      filter: alpha(opacity=10);
      opacity: 0.1;
      z-index: 4;
    }
    
    &:hover {
      color: rgba(#fff, 0.75);
      box-shadow: 0 0 10px 2px rgba(0, 0, 0, 0.7);
    }
    
    .image {
      height: 100%;
      flex: 1 0 200px;
      overflow: hidden;
      
      img {
        width: 100%;
        height: auto;
        object-fit: cover;
        object-position: center;
      }
      
      @media screen and (max-width: 480px) {
        flex-basis: 100%;
        width: 100%;
      }
    }
    
    .desc {
      position: relative;
      height: 100%;
      display: flex;
      flex-direction: column;
      padding-left: 1rem;
      align-self: flex-start;
      font-size: 15px;
      overflow: hidden;
      
      .btn {
        text-transform: uppercase;
        background-color: $bg-light;
        
        &:hover {
          color: rgba(#fff, 0.75);
          background-color: transparent;
        }
      }     
      
      @media screen and (max-width: 480px) {
        padding-left: 0;
        padding-top: 12px;
      }
    }

    &.item-hide {
      opacity: 0;
      transform: scale(.7);
    }

    &.item-focus {
      opacity: 1;
      transform: scale(1);
    }

    &.item-next {
      opacity: 1;
      transform: scale(1);

      & + .scroll-list__item {
        opacity: 1;
        transform: scale(1);
      }

    }
    
    // .scroll-list__item:first-child {
    //   margin-top: 48px;
    // }

    &:last-child {
      margin-bottom: 80px;
    }

    @media screen and (max-width: 768px) {
      margin-bottom: 12px;
      padding: 12px;
    }
    @media screen and (max-width: 480px) {
      flex-direction: column;
    }
  }

}

.scroll-list__item:first-of-type {
  margin-top: 32px;
}

// .scroll-list__item:last-of-type {
//   margin-bottom: 155px;
// }