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

body {
  margin: 0;
  font-family: 'Montserrat', sans-serif;
}

img {
  width: 100%;
  height: 100%;
}

h1,
h2,
h3 {
  margin: 0;
}

.header{
width: 100%;
padding: 15px 0;

text-align: center;
font-size: 24px;
font-weight: 300;
color: grey
}

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

.hero{
  min-height: 100vh;
  display: flex;
  justify-content: center;
}

.container{
  max-width: 1230px;
  width: 100%;
  margin: 0 auto;
  padding: 0, 15px;
}

.hero__container{
  display: grid;
  grid-template-columns: 
  repeat(auto-fit, minmax(290px, 1fr));
  grid-gap: 20px;
}

.hero__about{
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero__title{
  margin-bottom: 20px;
  font-size: 48px;
  line-height: 1.1;
}

.hero__subtitle{
  font-size: 32px;
  font-weight: 400;
}

.hero__links{
  display: flex;
}

.hero__link{
  margin-right: 10px;
  font-size: 30px;
  color: gold;

  transition: color 0.3s;
}

.hero__link:hover{
  color:blue;
}

.hero__box{
  max-width: 500px;
  justify-self: center;
  overflow: hidden;
  background-image: linear-gradient(to top, #30cfd0 0%, #330867 100%);
  border: 10px solid #ffffff;
  box-shadow: 2px 5px 10px
  rgba(0, 0, 0, 0.5);
  animation: ava-animate 5s infinite alternate;
}

.hero__box-img{
  animation: ava-bg 3s infinite alternate;
  align-items: center;
}

@media screen and (max-width: 978px){
  .hero{
    padding-top: 30px;
  }

  .hero__container{
    grid-row-gap: 20px;
  }

  .hero__title{
    font-size: 28px;
    margin-bottom: 10px;
  }

  .hero__subtitle{
    font-size: 22px;
    font-weight: 400;
  }

  .hero__description{
    font-size: 14px;
  }

  .hero__about{
    text-align: center;
  }

  .hero__links{
    justify-content: center;
  }

  .hero__box{
    max-width: 350px;
  }
}

@keyframes ava-animate{
  0%{
    border-radius: 48% 52% 57% 43% / 21% 24% 76% 79% ;
  }
  40%{
    border-radius: 68% 32% 30% 70% / 44% 51% 49% 56% ;
  }
  60%{
    border-radius: 9% 91% 84% 16% / 44% 20% 80% 56% ;
  }
  100%{
    border-radius: 0% 100% 0% 100% / 100% 0% 100% 0% ;
  }
}

@keyframes ava-bg{
  from{
    backgrop-filter: hue-rotate(0)
  }
  to{
    backdrop-filter: hue-rotate(90deg);
  }
}