* {
  box-sizing: border-box; /* chiều cao va chiều rộng sẽ ko bị thay đối khi bị tác động bới padding và border*/
}
:root {
  --color_primary: #1ebfc1;
}
html {
  font-size: 62.5%;
}
body {
  font-size: 1.6rem;
  font-family: "Poppins", sans-serif;
}
/* ===================================== common all =========================== */
.main-content {
  width: 1170px;
  max-width: calc(100% - 48px);
  margin-left: auto;
  margin-right: auto;
}
.btn {
  color: #fff;
  text-align: center;
  font-size: 1.8rem;
  font-weight: 600;
  border-radius: 14px;
  background: var(--color_primary);
  padding: 20px 40px;
}
.btn:hover {
  opacity: 0.8;
  transition: all ease 0.8s;
}
a {
  text-decoration: none;
  color: black;
}
.heading-lv2 {
  color: #0d1111;
  font-size: 6.2rem;
  font-weight: 700;
  line-height: 1.17; /* 116.129% */
}

/* ===================== code header nav ============== */
.heading .body__header {
  z-index: 1;
  position: sticky;
  top: -28px;
}
.body__header {
  display: flex;
  justify-content: space-between;
  margin-top: 30px;
  padding-bottom: 18px;
  position: relative;
}
.body__header .nav a:first-child {
  color: #2f3a3b;
  font-size: 1.6rem;
  font-weight: 600;
  text-shadow: none;
}
.body__header .nav a {
  display: inline-block;
  padding-left: 39px;
  padding-top: 12px;
  padding-bottom: 12px;
}
.body__header .nav a + a:hover {
  text-shadow: 1px 0 0 #2f3a3b;
  /* transition: all ease 0.9s; */
}
.body__header .btn--Sign_up.active {
  color: #1ebfc1;
  font-size: 1.6rem;
  font-weight: 600;
  border-radius: 6px;
  border: 1px solid var(--color_primary);
}
.heading .body__header .group-btn {
  margin-top: 10px;
}
.heading .body__header .btn {
  padding: 12px 24px;
  background-color: transparent;
}
.heading .body__header .btn--Sign_in {
  color: #494949;
  text-align: center;
  font-size: 1.6rem;
}
/* code hero */
.info {
  display: flex;
  gap: 70px;
}
.hero .info {
  margin-top: 40px;
}
.info .hero__left {
  width: 40%;
}
.info .hero__left .desc {
  margin-top: 93px;
  color: #767e7e;
  font-size: 1.4rem;
  font-weight: 400;
}
.info .hero__left .title {
  margin-top: 18px;
}
.info .label {
  color: #9da6a5;
  font-size: 1.8rem;
  line-height: 1.78; /* 177.778% */
  margin-top: 46px;
  max-width: 370px;
}
.info .btn--get_Started {
  width: 186px;
  height: 68px;
  padding: 20px 40px;
  margin-right: 50px;
  text-align: center;
}
.info .cta {
  display: flex;
  margin-top: 52px;
  justify-content: left;
  align-items: center;
}
.info .cta .play {
  flex-shrink: 0;
  padding: 22px;
  cursor: pointer;
  border-radius: 62px;
}
.info .cta .play:hover {
  background: #9d9999;
  box-shadow: 0px 22px 50px 0px rgba(0, 0, 0, 0.05);
}
/* hero-right */
.hero .hero__right .img_teacher {
  width: 576px;
  height: 631px;
  background-position: top;
  /* object-fit: cover; */
  margin-left: 65px;
}
.info .Courses {
  display: flex;
  border-radius: 18px;
  background: #fefefd;
  box-shadow: 0px 10px 80px 0px rgba(0, 0, 0, 0.05);
  width: 157px;
  height: 75px;
  justify-content: center;
  align-items: center;
  position: absolute;
  left: 25px;
  top: 150px;
  padding: 18px 25px;
}
.info .Courses p {
  color: #0d1111;
  font-size: 1rem;
  font-weight: 500;
  /* width: 55px; */
  margin-left: 16px;
}
.hero .hero__right {
  position: relative;
}
.hero .Schedules {
  width: 124px;
  height: 132px;
  border-radius: 24px;
  background: #fff;
  box-shadow: 0px 10px 80px 0px rgba(0, 0, 0, 0.05);
  padding: 16px 25px 45px;
  position: absolute;
  left: 0px;
  bottom: 125px;
}
.hero .Schedules span {
  display: inline-block;
  color: #0d1111;
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 16px;
}
.hero .hero__right .Our_Active_Students {
  padding: 17px 35px 8px 35px;
  width: 207px;
  height: 90px;
  border-radius: 24px;
  background: #fefefd;
  box-shadow: 0px 12px 80px 0px rgba(0, 0, 0, 0.05);
  position: absolute;
  right: 45px;
  bottom: 120px;
}
.hero .hero__right .Our_Active_Students span {
  display: inline-block;
  color: #0d1111;
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 8px;
}
.features {
  margin-top: 130px;
}
.features .features__top span {
  color: #767e7e;
  font-size: 1.2rem;
  font-weight: 700;
}
.features .features__top .heading-lv2 {
  font-size: 4.2rem;
  line-height: 1.34; /* 133.333% */
  width: 577px;
  margin-top: 18px;
}
.features .features__top .desc {
  color: #767e7e;
  font-size: 1.8rem;
  margin-top: 18px;
  width: 590px;
}
.body_features .feature__list {
  display: flex;
  margin-top: 80px;
}
.body_features .feature__list .feature__item {
  width: 33.33%;
}
.body_features .feature__list .feature__item .heading-lv2 {
  margin-top: 26px;
  color: #0d1111;
  font-family: Poppins;
  font-size: 2rem;
  font-weight: 600;
}
.body_features .feature__list .feature__item .desc {
  width: 223px;
  color: #9da6a5;
  font-size: 1.6rem;
  line-height: 1.69; /* 168.75% */
  margin-top: 16px;
}
/*==================== popular top ====================== */
.popular {
  margin-top: 130px;
}
.popular .courses {
  color: #767e7e;
  font-size: 1.2rem;
  font-style: normal;
  font-weight: 700;
  line-height: normal;
}
.popular .popular__top .heading-lv2 {
  width: 577px;
  font-size: 4.2rem;
  margin: 18px 0px 18px 0px;
}
.popular .popular__top .content {
  display: flex;
  justify-content: space-between;
}
.popular .popular__top .desc {
  max-width: 525px;
  /* width: 525px; */
  color: #767e7e;
  font-size: 1.8rem;
  line-height: 1.78; /* 177.778% */
}
.popular .popular__top a {
  color: #1ebfc1;
  font-size: 1.4rem;
  font-weight: 700;
  text-decoration-line: underline;
}
.popular__item {
  margin-top: 80px;
  position: relative;
  width: 31%;
}
.popular__main .container .heading-lv2 {
  color: #0d1111;
  font-size: 2.2rem;
  font-style: normal;
  font-weight: 700;
  line-height: normal;
  margin-top: 16px;
  margin-left: 25px;
}
.popular__main .container {
  width: 325px;
  height: 195px;
  flex-shrink: 0;
  border-radius: 8px;
  background: #fff;
  box-shadow: 0px 16px 90px 0px rgba(0, 0, 0, 0.05);
  position: absolute;
  bottom: -151px;
  left: 17px;
  right: auto;
}
.popular__main .container .desc {
  color: #767e7e;
  font-size: 1.6rem;
  margin-top: 6px;
  margin-left: 25px;
}
.popular__main .container .heading {
  margin-top: 16px;
  margin-left: 25px;
}
.popular__main .container strong {
  color: #0d1111;
  font-size: 2.2rem;
  font-weight: 700;
}
.popular__main .container span::before {
  margin-right: 10px;
  width: 6px;
  height: 6px;
  content: "";
  display: inline-block;
  background-color: var(--color_primary);
  border-radius: 50%;
  margin-bottom: 2px;
}
.popular__main .container span {
  margin-right: 10px;
}
.popular__main .container .time {
  margin-top: 18px;
}
.popular__main .popular__list .img {
  border-radius: 8px;
  opacity: 0.35;
  background: #d0efed;
  border-radius: 8px;
  opacity: 0.4;
  background: #d0efed;
}
.popular__main .popular__list {
  display: flex;
  gap: 40px;
}
/* =========================== countdown ==================== */
.countdown {
  margin-top: 327px;
}
.countdown__list {
  display: flex;
  width: 862px;
  height: 131px;
  /* width: 74vh; */
  gap: 200px;
  margin-left: 156px;
}
.countdown__item {
  justify-content: center;
  align-items: center;
  flex-shrink: 0;
  gap: 202px;
}
.countdown__item .desc {
  margin-top: 11px;
  color: #767e7e;
  text-align: center;
  font-size: 1.8rem;
}
/* ============================ block ===================== */
.block {
  margin-top: 264px;
}
.block__item {
  display: flex;
  gap: 72px;
}
.item__left {
  width: 36%;
}
.block__item .item__img {
  margin: 37px 0px 27px 0px;
}
.block__item .desc {
  color: #5d6564;
  font-size: 3.2rem;
  line-height: 1.5; /* 150% */
  margin-bottom: 33px;
}
.block__item .desc strong {
  color: #070707;
  font-size: 1.6rem;
  font-weight: 500;
}
.block__item .desc strong::before {
  display: inline-block;
  content: "";
  width: 8px;
  height: 2px;
  flex-shrink: 0;
  background: #070707;
  margin: 5px;
}
.block__item .desc__student {
  color: #767e7e;
  font-size: 1.6rem;
}
.btn--next {
  display: flex;
  width: 50px;
  height: 50px;
  flex-shrink: 0;
  gap: 30px;
}
.btn--next-left {
  width: 50px;
  height: 50px;
  flex-shrink: 0;
  border-radius: 50px;
  background: var(--color_primary);
  display: flex;
  justify-content: center;
  align-items: center;
}
.btn--next-right {
  width: 50px;
  height: 50px;
  flex-shrink: 0;
  border-radius: 50px;
  background: var(--color_primary);
  display: flex;
  justify-content: center;
  align-items: center;
}
/* code phan block right */
.item__right .image {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  width: 676px;
}
.item__right .img__item1 {
  background-color: #ff8282;
  border-radius: 50%;
  margin: 15% auto;
}
.item__right .img__item2 {
  display: flex;
  position: absolute;
  left: 144px;
  top: 0px;
}
.item__right .img__item3 {
  display: flex;
  position: absolute;
  right: 0;
  background-color: #bf83ff;
  border-radius: 50%;
  top: 20px;
}
.item__right .img__item4 {
  display: flex;
  position: absolute;
  left: 0;
  bottom: 106px;
}
.item__right .img__item5 {
  display: flex;
  position: absolute;
  left: 145px;
  bottom: 0px;
}
.item__right .img__item6 {
  display: flex;
  position: absolute;
  right: 32px;
  bottom: 32px;
}
/* ================= action ========================= */
.action {
  background-color: #def6f5;
  margin-top: 130px;
  height: 272px;
}
.action__left {
  width: 50%;
  text-align: center;
  margin-top: 76px;
}
.action__left .heading-lv2 {
  font-size: 4.2rem;
  font-weight: 700;
  margin-bottom: 18px;
}
.action__left .desc {
  color: #767e7e;
  font-size: 1.6rem;
}
.action__right {
  margin-top: 96px;
  margin-left: 155px;
}
.btn__started {
  display: flex;
  justify-self: center;
  border: unset;
  cursor: pointer;
}
/* ================== footer ================= */
.footer .footer__info {
  display: flex;
  margin-top: 131px;
}
.footer .heading-lv2 {
  color: #2e2e2e;
  font-size: 1.8rem;
  font-weight: 500;
  margin-bottom: 25px;
}
.footer__info .info__item {
  width: 20%;
}
.footer__info .info__item li {
  margin-bottom: 20px;
  color: #535353;
  font-size: 1.6rem;
}
.footer .info__item li a {
  display: flex;
}
.info__item li a .desc {
  margin-left: 9px;
  color: #535353;
  font-size: 1.6rem;
}
.copyright {
  text-align: center;
  margin-top: 80px;
  margin-bottom: 50px;
  color: #b0b5b4;
}