html {
  box-sizing: border-box;
}

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

img {
  max-width: 100%;
}

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

:root {
  --main-color: #3f2aff;
  --white-color: #fff;
  --gray-color: #666;
  --sapphire-blue-color: #212133;
  --granite-color: #2e2b44;
  --purplish-blue-color: #85859b;
  --bg-card-color: #edf0f9;
}

@font-face {
  font-family: 'Roboto';
  src: local('Roboto-Regular'),
    url("../fonts/Roboto-Regular.woff2") format("woff2"),
    url("../fonts/Roboto-Regular.woff") format("woff");
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Roboto';
  src: local('Roboto-Bold'),
    url("../fonts/Roboto-Bold.woff2") format("woff2"),
    url("../fonts/Roboto-Bold.woff") format("woff");
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

.page {
  font-family: 'Roboto', sans-serif;
  font-weight: 400;
}

/* glob */
.list-reset {
  margin-top: 0;
  margin-bottom: 0;
  padding: 0;
  list-style: none;
}

.flex {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
}

.btn-reset {
  border: none;
  background-color: transparent;
  cursor: pointer;
}

.btn {
  display: block;
  padding: 20px 59px;
  max-width: -webkit-max-content;
  max-width: -moz-max-content;
  max-width: max-content;
  font-weight: 700;
  font-size: 16px;
  line-height: normal;
  color: var(--white-color);
  background-color: var(--main-color);
  border-radius: 20px;
}

.section-title {
  margin: 0;
  margin-bottom: 30px;
  font-weight: 700;
  font-size: 40px;
  line-height: 100%;
}

.section-offset {
  padding-top: 80px;
  padding-bottom: 80px;
}

/* header */
.header {
  background-color: var(--main-color);
}

.header__container {
  padding-top: 28px;
  padding-bottom: 27px;
}

.logo {
  margin-right: auto;
}

.nav__list {
  gap: 56px;
}

.nav__link {
  font-size: 18px;
  line-height: normal;
  color: var(--white-color);
}

/* hero */
.hero {
  padding-top: 15px;
  padding-bottom: 15px;
  background: -o-radial-gradient(67.78% 55.93%, 44.07% 44.07%, #555681 0%, #212133 100%);
  background: radial-gradient(44.07% 44.07% at 67.78% 55.93%, #555681 0%, #212133 100%);
}

.hero__container {
  padding-top: 115px;
  padding-bottom: 115px;
  background-image: url('../img/hero-bg.png');
  background-repeat: no-repeat;
  background-position: right 15px center;
  background-size: contain;
}

.hero__title {
  margin: 0;
  margin-bottom: 28px;
  font-weight: 700;
  font-size: 60px;
  line-height: 100%;
  color: var(--white-color);
}

.hero__descr {
  margin: 0;
  margin-bottom: 62px;
  font-size: 18px;
  line-height: 150%;
  color: var(--white-color);
}

.hero__btn {
  padding: 24px 75.5px;
  font-size: 18px;
}

/* advantages */
.advantages {
  padding-bottom: 74px;
}

.advantages__top {
  margin-bottom: 18px;
}

.advantages__image {
  background-image: url('../img/advantages-descr.png');
  background-repeat: no-repeat;
  background-position: top 24px left 15px;
  background-size: calc(100% - 30px);
}

.advantages__title {
  margin-bottom: 17px;
  max-width: 74%;
  color: var(--granite-color);
}

.advantages__descr {
  margin: 0;
  font-size: 16px;
  line-height: 150%;
  color: var(--gray-color);
}

.advantages__item {
  padding: 16px 0 16px 110px;
  background-repeat: no-repeat;
  background-size: 80px;
  background-position: left center;
}

.advantages__item-1 {
  background-image: url('../img/advantages-1.svg');
}

.advantages__item-2 {
  background-image: url('../img/advantages-2.svg');
}

.advantages__item-3 {
  background-image: url('../img/advantages-3.svg');
}

.advantages__text {
  margin: 0;
  font-weight: 700;
  font-size: 16px;
  line-height: 120%;
  color: var(--gray-color);
}

/* teachers */
.teachers {
  padding-top: 75px;
  padding-bottom: 73px;
  background-color: var(--sapphire-blue-color);
}

.teachers__title {
  margin-bottom: 23px;
  color: var(--white-color);
}

.teachers__img {
  display: block;
  margin-bottom: 31px;
  font-size: 0;
}

.teachers__img img,
.teachers__img source {
  border-radius: 20px 20px 0px 0px;
}

.teachers__name {
  margin: 0;
  margin-bottom: 7px;
  font-weight: 700;
  font-size: 18px;
  line-height: 150%;
  color: var(--white-color);
}

.teachers__text {
  margin: 0;
  font-size: 16px;
  line-height: 150%;
  color: var(--purplish-blue-color);
}

/* courses */
.courses {
  padding-top: 75px;
  padding-bottom: 82px;
}

.courses__title {
  margin-bottom: 23px;
  color: var(--sapphire-blue-color);
}

.courses__list {
  row-gap: 30px;
}

.courses__item {
  position: relative;
  padding: 210px 30px 30px;
  height: 100%;
  background-color: var(--bg-card-color);
  border-radius: 20px;
}

.courses__item::before {
  position: absolute;
  content: "";
  top: 0;
  left: 0;
  width: 100%;
  height: 180px;
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
  border-radius: 20px 20px 0px 0px;
}

.courses__item-1::before {
  background-image: url('../img/cinema-bg.jpg');
}

.courses__item-2::before {
  background-image: url('../img/blender-bg.jpg');
}

.courses__item-3::before {
  background-image: url('../img/visualization-bg.jpg');
}

.courses__item-4::before {
  background-image: url('../img/sculpting-bg.jpg');
}

.courses__time {
  position: absolute;
  top: 12px;
  right: 4px;
  padding-left: 29px;
  font-size: 16px;
  line-height: normal;
  color: var(--white-color);
  background-image: url(../img/time.svg);
  background-repeat: no-repeat;
  background-position: left center;
  background-size: 24px;
}

.courses__preview {
  -webkit-box-orient: vertical;
  -webkit-box-direction: normal;
  -ms-flex-direction: column;
  flex-direction: column;
  -webkit-box-pack: justify;
  -ms-flex-pack: justify;
  justify-content: space-between;
  height: 100%;
}

.courses__caption {
  margin: 0;
  margin-bottom: 8px;
  font-weight: 700;
  font-size: 18px;
  line-height: 150%;
  color: var(--sapphire-blue-color);
}

.courses__text {
  margin: 0;
  margin-bottom: 49px;
  font-size: 16px;
  line-height: 150%;
  color: var(--gray-color);
}

/* footer */
.footer {
  text-align: center;
}

.footer__top {
  padding-top: 28px;
  padding-bottom: 28px;
  background-color: var(--granite-color);
}

.social__list {
  -webkit-box-pack: center;
  -ms-flex-pack: center;
  justify-content: center;
  gap: 30px;
}

/* .social__item {
  width: 24px;
  height: 24px;
} */

.social__link {
  display: block;
  width: 24px;
  height: 24px;
}

.footer__bottom {
  padding-top: 1px;
}

.footer__reg {
  font-size: 13px;
  line-height: normal;
  color: var(--granite-color);
}

.footer__reg-sign {
  color: var(--main-color);
}