@keyframes rotation {
  from {
    transform: rotate(-15deg);
  }

  to {
    transform: rotate(345deg);
  }
}

.page {
  min-width: 1100px;
  /* мы ещё не умеем делать мобильную версию сайта, */
  /* поэтому выше установлена минимальная ширина страницы */
  max-width: 1600px;
  /* выше установили ограничение по максимальной ширине */
  margin: 0 auto;
  /* выше для экранов больше 1600px отцентрировали весь контент */
  font-family: 'Helvetica Neue', 'Arial', sans-serif;
  box-sizing: border-box;
}

.header {
  height: 100vh;
  min-height: 600px;
  max-height: 756px;
  display: flex;
  align-items: center;
  background-color: #F2F2F2;
  position: relative;
  /* выше установили ограничения для секции */
  overflow: hidden;
}

.logo {
  position: absolute;
  width: 183px;
  height: 32px;
}

.logo_place_header {
  top: 30px;
  left: 64px;
  background-image: url('../images/logo.svg');
  background-size: contain;
  background-repeat: no-repeat;
  z-index: 2;
}

.header__title {
  line-height: 96px;
  font-size: 102px;
  font-weight: 700;
  width: 730px;
  margin-left: 64px;
}

.header__subtitle {
  line-height: 25px;
  font-size: 18px;
  font-weight: normal;
  width: 388px;
  position: absolute;
  left: 64px;
  bottom: 30px;
}

.header__link {
  text-decoration: none;
  color:  #2F80ED;
  opacity: 1;
  transition: .2s linear;
}

.header__link:hover {
  opacity: .7;
}

.header__main-illustration {
    width: 765px;
    height: 608px;
    position: absolute;
    right: 0;
    bottom: 0;
    z-index: 1;
}

.header__square-pic {
  width: 568px;
  height: 568px;
  background-color: #2F80ED;
  position: absolute;
  top: 64px;
  right: 0;
  animation: rotation 20s linear infinite;
}

.description {
  display: flex;
  justify-content: center;
  padding-top: 100px;
  /*padding-bottom: 100px;*/
}

.two-columns {
  display: flex;
  justify-content: space-between;
  width: 80%;
}

.two-columns__brief {
  width: 175px;
  line-height: 1.2;
  font-size: 18px;
  font-weight: normal;
  color: #2F80ED;
  margin-top: 0;
}

.two-columns__main-text {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  width: 80%;
  min-width: 784px;
}

.two-columns__span-accent {
  font-weight: 700;
}

.two-columns__paragraph {
  line-height: 34px;
  font-size: 24px;
  font-weight: normal;
  margin-bottom: 30px;
  margin-top: 0;
}

.two-columns__paragraph:last-of-type {
  margin-bottom: 0;
}

.technics {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 100px;
}

.cards {
  /* border: 1px solid salmon; */
  width: 80%;
  width: 920px;
  margin: 0 auto;
  display: flex;
  justify-content: flex-start;
  flex-wrap: wrap;
}

.cards__item {
  /* border: 1px solid salmon; */
  width: 240px;
  margin-top: 60px;
  margin-right: 100px;
}

.cards__item.cards__item:nth-child(3n) {
  margin-right: 0;
}

.cards__image {
  width: 160px;
  height: 160px;
  margin-left: 40px;
  margin-right: 40px;
  margin-bottom: 43px;
  border-radius: 50%;
}

.cards__title {
  margin-bottom: 16px;
  text-align: center;
  line-height: 1.15;
  font-size: 24px;
  font-weight: 700;
}

.cards__description {
  text-align: center;
  line-height: 23px;
  font-size: 18px;
  font-weight: normal;
}

.video {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 100px;
}

.video__iframes {
  margin-top: 50px;
  width: 1050px;
  height: 316px;
  display: flex;
}

.video__iframe {
  margin-right: 20px;
  border: 0;
}

.video__iframe:last-child {
  margin-right: 0;
}

.oacley {
  margin-top: -80px;
  padding-top: 160px;
  padding-bottom: 80px;
  background-color: #F2F2F2;
  display: flex;
  justify-content: center;
  align-items: center;
}

.digits {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 100px;
  /* padding-bottom: 100px; */
  /* margin-top: -100px; */
}

.section-title {
  width: 60%;
  margin-bottom: 20px;
  margin-top: 0;
  text-align: center;
  font-size: 60px;
  line-height: 1.15;
  font-weight: 700;
}

.section-subtitle {
  margin-top: 0;
  margin-bottom: 0;
  width: 60%;
  text-align: center;
  font-size: 24px;
  line-height: 34px;
  font-weight: normal;
}

.table {
  display: flex;
  justify-content: space-between;
  flex-direction: row;
  flex-wrap: wrap;
  width: 1100px;
}

.table__cell {
  width: 250px;
  margin-top: 60px;
}

.table__heading {
  margin-bottom: 20px;
  margin-top: 0;
  font-size: 24px;
  line-height: 1.15;
  font-weight: 700;
}

.table__text {
  margin-bottom: 20px;
  font-size: 18px;
  line-height: 1.2;
  font-weight: normal;
}

.table__text:last-of-type {
  margin-bottom: 0;
}

.khan {
  padding-top: 105px;
  background-color: #F2F2F2;
  position: relative;
  top: 100px;
  display: flex;
  justify-content: center;
}

.khan__container {
  width: 80%;
  display: flex;
  flex-direction: column;
}

.khan__author {
  margin-top: 0;
  margin-bottom: 0;
  line-height: 42px;
  font-size: 30px;
  font-weight: normal;
}

.khan__title {
  margin-top: 0;
  margin-bottom: 50px;
  line-height: 1.15;
  font-size: 60px;
  font-weight: 700;
}

.khan__quote {
  margin: 0;
  margin-bottom: 36px;
  width: 790px;
  line-height: 34px;
  font-size: 24px;
  font-weight: normal;
}

.khan__quote-author {
  margin-top: 0;
  margin-bottom: 10px;
  line-height: 1.15;
  font-size: 24px;
  font-weight: 700;
}

.khan__quote-author-subline {
  margin-top: 0;
  margin-bottom: 68px;
  line-height: 1.15;
  font-size: 24px;
  font-weight: normal;
}

.khan__book-container {
  display: flex;
  justify-content: flex-start;
  overflow: hidden;
}

.khan__book-pic {
  object-fit: cover;
  object-position: 0 0;
  width: 620px;
  height: 708px;
  margin-right: 20px;
}

.khan__buy-link {
  color: #2F80ED;
  text-decoration: none;
  opacity: 1;
  transition: .2s linear;
  line-height: 42px;
  font-size: 30px;
  font-weight: normal;
}

.khan__buy-link:hover {
  opacity: .7;
}

.feinman {
  height: 790px;
  display: flex;
  flex-direction: column;
  align-items: center;
  background-color: #F2F2F2;
  position: relative;
  background-image: url('../images/feinman.png');
  background-position: left bottom;
  background-repeat: no-repeat;
  background-size: 867px 637px;
  /* padding-top: 100px; */
}

.feinman__title {
  margin-top: 0;
  margin-bottom: 70px;
  width: 648px;
  text-align: center;
  line-height: 1.15;
  font-size: 120px;
  font-weight: 700;
  z-index: 1;
}

.feinman__subtitle {
  margin-top: 0;
  line-height: 51px;
  font-size: 36px;
  font-weight: normal;
  z-index: 1;
}

.feinman__link {
  text-decoration: none;
  color:  #000;
  opacity: 1;
  transition: .2s linear;
  position: absolute;
  right: 48px;
  top: 50%;
  line-height: 51px;
  font-size: 36px;
  font-weight: normal;
  z-index: 1;
}

.feinman__link:hover {
  opacity: .6;
}

.feinman__image {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 867px;
  height: 637px;
}

.kaufman {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 90px;
  padding-bottom: 90px;
  background-color: #1F1F1F;
  position: relative;
  overflow: hidden;
}

.section-title_theme_dark {
  color: #FFF;
  z-index: 1;
}

.section-subtitle_theme_dark {
  color: #FFF;
  z-index: 1;
}

.table_theme_dark {
  color: #FFF;
  z-index: 1;
}

.table__cell_theme_dark {
  width: 200px;
  margin-top: 80px;
}

.kaufman__triangle {
  margin: 0;
  width: 877px;
  height: 877px;
  position: absolute;
  background-image: url('../images/triangle.svg');
  top: 0;
  right: -210px;
  background-size: contain;
  animation: rotation 20s linear infinite;
}

.resourses {
  padding-top: 100px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.resourses__logo-zone {
  margin-top: 80px;
  margin-bottom: 217px;
  display: grid;
  grid-template-columns: repeat(4, 270px);
  grid-auto-rows: 38px;
  grid-gap: 0px;
  width: 1100px;
  list-style-type: none;
}

.resourses__logo {
  align-self: center;
  justify-self: center;
  object-fit: cover;
  height: 100%;
  opacity: 1;
  transition: .2s linear;
}

.resourses__logo:hover {
  opacity: .5;
}

.resourses__image {
  height: 100%;
}

.footer {
  display: flex;
  justify-content: center;
  padding-top: 60px;
  padding-bottom: 40px;
  background-color: #1F1F1F;
  color: #FFF;
  min-height: 350px;
}

.footer__columns {
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  width: 90%;
}

.footer__column_content_copyright {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  position: relative;
  flex-basis: 711px;
}

.logo_place_footer {
  top: 0;
  left: 0;
  background-image: url('../images/logo_white.svg');
  background-size: cover;
}

.footer__author {
  line-height: 25px;
  font-size: 18px;
  font-weight: normal;
  margin-top: 18px;
  margin-bottom: 18px;
}

.footer__column_content_info {
  flex-wrap: wrap;
}

.footer__column-heading {
  line-height: 30px;
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 20px;
}

.footer__column-links {
  line-height: 30px;
  font-size: 18px;
  font-weight: normal;
  text-decoration: none;
  margin-bottom: 16px;
  padding-left: 0;
}

.footer__list-item {
  list-style-type: none;
}

.footer__column-link {
  text-decoration: none;
  color: #FFF;
  opacity: 1;
  transition: .2s linear;
}

.footer__social-icon {
  width: 16px;
  height: 16px;
}

.footer__column-link:hover {
  opacity: .5;
}