:root {
  --main-bg-color: #ffffff;
  --second-bg-color: #DADADA;
  --accent-color: #18CFAB;

  --main-text-color: ##777777;
  --accent-text-color: #18CFAB;
  --title-color: #4E4E4E;

  --accent-button-color: #00CBF6;

  --transitionTimingFunction: 250ms cubic-bezier(0.075, 0.82, 0.165, 1);
}

html {
  scroll-behavior: smooth;
}

body {
  position: relative;

  font-family: 'Montserrat', sans-serif;
  font-weight: 400;
  font-style: normal;
  line-height: 1.111; 
  letter-spacing: 0.03em;
  color: var(--main-text-color);

  background-color: var(--main-bg-color);
}

.container {
  width: 1200px;
  margin-right: auto;
  margin-left: auto;
  padding-right: 20px;
  padding-left: 20px;
}

.link {
 color:inherit;
 text-decoration: none;
}

.list > .item {
  list-style: none;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

.title {
  position: relative;
  text-align: center;
  font-weight: 400;
  font-size: 36px;
  color: var(--title-color);
}

.title-elements::before {
  content: "";
  position: absolute;
  top: 150%;
  right: 50%;
  transform: translateX(30%);
  display: block;
  height: 1px;
  width: 75px;
  background-color: var(--accent-text-color);
}

.title-elements::after {
  content: "";
  position: absolute;
  top: 165%;
  right: 50%;
  transform: translateX(50%);
  display: block;
  height: 1px;
  width: 78px;
  background-color: var(--accent-text-color);
}

.button {
  margin-left: auto;
  margin-right: auto;
  width: 168px;
  height: 63px;
  border: 0;
  border-radius: 5px;
  background-color: var(--accent-color);
  font-weight: 700;
  font-size: 15px;
  text-transform: uppercase;
  color: #FFFFFF;

  transition: background-color var(--transitionTimingFunction);

  box-shadow: 0 -5px #ffffff;
}

.button:hover,
.button:focus {
  cursor: pointer;
  background-color: var(--accent-button-color);
}

.icon {
  fill: currentColor;
}

.hide {
  opacity: 1;
  animation-name: anime;
  animation-duration: 1500ms;
  animation-fill-mode: forwards;
}

@keyframes anime {
  to{
    opacity: 0;
    height: 0;
    width: 0;
    margin: 0;
    padding: 0;
    border: 0;
  }
}

#btnUp {
  position: fixed;
  top: 90%;
  right: 10px;
  display: block;
  padding: 3px;
  border: 1px solid var(--accent-color);
  border-radius: 50%;
  width: 50px;
  height: 50px;
  font-size: 14px;
  font-weight: bold;
  color: #ffffff;
  background-color: rgba(31, 218, 181, 0.5);
  transition: background-color var(--transitionTimingFunction);
}

#btnUp:hover,
#btnUp:focus {
  background-color: var(--accent-button-color);
  cursor: pointer;
}

#btnUp::before,
#btnUp::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

#btnUp::before {
  border-top-right-radius: 3px;
  border-top-left-radius: 3px;
  width: 5px;
  height: 20px;
  background-color: #fff;
}

#btnUp::after {
  width: 15px;
  height: 15px;
  transform: translate(-50%, -50%) rotate(45deg);
  border-top: 5px solid #fff;
  border-left: 5px solid #fff;;
}