* {
  margin: 0;
  padding: 0;
  font-size: 62.5%;
  font-family: sans-serif;
}

html {
  scroll-behavior: smooth;
}

body {
  background-color: #040814;
  box-sizing: border-box;
}

/* ---------------------------------------- header ----------------------------------------  */

header {
  width: 100%;
  height: 100vh;
  background-image: url(images/main.jpg);
  background-repeat: no-repeat;
  background-size: cover;
}

/* ------------------- go-back ------------------- */

.go-back {
  position: relative;
  width: 14.8rem;
  height: 4.8rem;
  margin-left: 5rem;
  border-radius: 0.4rem;
  background-color: rgba(0, 0, 0, 0.8);
  border: 1px solid silver;
  cursor: pointer;
  text-align: center;
  align-items: center;
  transition: all 0.3s;
}

.go-back a {
  font-size: 4rem;
  color: white;
}

.go-back:hover {
  background-color: #fff;
}

.go-back:hover a {
  color: #000;
  transition: all 0.3s;
  font-weight: 100;
}

/* ---------------------------------------- navbar ---------------------------------------- */

.navbar {
  width: 100%;
  height: 9vh;
  margin: auto;
  position: relative;
}

.navbar-bg {
  width: 100%;
  height: 9vh;
  position: fixed;
  opacity: 0;
  z-index: 98;
  transition: 0.5s all ease;
  display: flex;
  justify-content: center;
  align-items: center;
}

.navbar-bg img {
  width: 50px;
  height: 50px;
}

.navbar .navbar-bg.active {
  background-color: #040714;
  opacity: 1;
}

.navbar-content {
  position: fixed;
  width: 100%;
  height: 9vh;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 99;
}

.nav-btn {
  width: 15rem;
  height: 5rem;
  border-radius: 0.4rem;
  margin-right: 5rem;
  background-color: rgba(0, 0, 0, 0.8);
  border: 1px solid silver;
  cursor: pointer;
  transition: all 0.3s;
}

.nav-btn:hover {
  background-color: #fff;
}

.nav-btn a {
  text-decoration: none;
  color: rgb(238, 227, 227);
  font-size: 2rem;
  font-weight: 500;
}

.nav-btn:hover a {
  color: #000;
  font-weight: 100;
}

/* ---------------------------------------- header section ---------------------------------------- */

.header-section {
  width: 90%;
  height: 80vh;
  position: absolute;
  top: 10%;
  left: 5%;
  display: grid;
  grid-template-columns: 36% auto;
}

.header-section__left img {
  width: 18rem;
  margin-top: 18%;
  margin-bottom: 2rem;
}

.header-section__left h1 {
  font-size: 4.4rem;
  color: #f9f9f9;
  line-height: 5.4rem;
  font-weight: 700;
  letter-spacing: normal;
  margin-bottom: 3rem;
}

.header-p-1 {
  font-size: 2rem;
  color: #c0c0c0;
  margin-bottom: 2.4rem;
}

.header-form {
  width: 100%;
  height: 5.2rem;
  display: grid;
  grid-template-columns: 75% 25%;
  margin-bottom: 2.5rem;
}

.header-form input {
  height: 50px;
  font-size: 3rem;
  padding: 0 1.2rem;
  background-color: #31343e;
  border: 1px solid #31343e;
  border-radius: 4px 0 0 4px;
  outline: none;
  color: #fff;
}

.header-form input::placeholder {
  font-size: 2rem;
}

.header-button-1 {
  font-size: 2rem;
  border: 1px solid #0063e5;
  background-color: #0063e5;
  color: #fff;
  border-radius: 0 4px 4px 0;
  cursor: pointer;
}

.header-p-2 {
  font-size: 2rem;
  color: #c0c0c0;
  margin-bottom: 2.5rem;
}

.header-down-arrow {
  width: 100%;
  height: 10rem;
  margin-top: 25rem;
  transform: translateY(0);
  animation: a1 1.5s infinite ease-out;

  /* animation-name: a1;
  animation-duration: 1.5s;
  animation-timing-function: ease;
  animation-iteration-count: infinite; */
}

@keyframes a1 {
  0%,
  25%,
  75%,
  100% {
    transform: translateY(0);
  }

  12.5% {
    transform: translateY(-12px);
  }

  37.5% {
    transform: translateY(-8px);
  }
}

.header-down-arrow a {
  color: #f9f9f9;
  font-size: 3.6rem;
  text-align: center;
}

/* ---------------------------------------- main-1 ---------------------------------------- */

.main {
  width: 100%;
  position: relative;
}

.main-bg {
  position: absolute;
  width: 100%;
  height: 100vh;
  background-image: url(images/menu.jpg);
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center;
}

.main-section {
  width: 90%;
  height: 100vh;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 40%;
}

.main-section__text {
  z-index: 89;

  width: 100%;
  height: 40%;
  margin: auto 0;
}

.main-section__text h1 {
  font-size: 4.4rem;
  color: #f9f9f9;
  margin-bottom: 3rem;
}

.main-section__text p {
  font-size: 2rem;
  color: #c0c0c0;
  letter-spacing: 0.2px;
}

/* ---------------------------------------- main-2 ---------------------------------------- */

.main-2 {
  width: 90%;
  height: 140vh;
  margin: 0 auto;
  font-size: 4.4rem;
  color: #fff;
  position: relative;
  text-align: center;
}

.main-2 h1 {
  font-size: 4.4rem;
  color: #f9f9f9;
}

.main-2 p {
  font-size: 2rem;
  color: #c0c0c0;
  margin: 3rem 0;
}

.main-2-bg {
  width: 100%;
  height: 77vh;
  background-image: url(images/menu-2.jpg);
  background-position: center;
  background-size: cover;
}

.main-list {
  margin-top: 4rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  list-style: none;
}

.main-item {
  display: flex;
  flex-direction: column;
}

.main-item h2 {
  font-size: 2.8rem;
  margin: 2rem 0;
}

/* ---------------------------------------- drop-down-menu ---------------------------------------- */

.drop-down-menu {
  width: 90%;
  height: auto;
  margin: 6rem auto;
  text-decoration: none;
}

.drop-down-menu h1 {
  font-size: 4.4rem;
  color: #f9f9f9;
  text-align: center;
  margin-bottom: 3rem;
}

.drop-down-item {
  height: auto;
  padding: 20px;
  background-color: #13151c;
  margin-bottom: 2rem;
}

/* menu open - close */

.positive {
  display: none;
}

.negative {
  display: none;
}

/* item 1 top */

.drop-down-item-top {
  width: 100%;
  background-color: #13151c;
  display: flex;
  justify-content: space-between;
}

.drop-down-item-top p {
  align-self: center;
  display: block;
  color: #f9f9f9;
  font-size: 2rem;
}

.drop-down-item-top a {
  display: block;
  text-decoration: none;
  font-size: 3rem;
  margin: auto 2rem;
  color: #f9f9f9;
}

/* item 1 bottom */

.drop-down-item-bottom {
  width: 100%;
  height: auto;
  background-color: #13151c;
  display: none;
  margin-top: 2rem;
}

.drop-down-item-bottom.active {
  display: block;
}

.drop-down-item-bottom p {
  align-self: center;
  display: block;
  color: #c0c0c0;
  font-size: 2rem;
}

.drop-down-item-bottom p:nth-child(2) {
  margin: 2rem 0;
}

.drop-down-item-bottom ul {
  margin-left: 4rem;
  color: #c0c0c0;
  font-size: 3rem;
}

.drop-down-item-bottom ul li {
  margin: 2rem 0;
}

/* ---------------------------------------- footer-device ---------------------------------------- */

.footer-device {
  width: 90%;
  height: 100%;
  margin: 0 auto;
}

.footer-device h1 {
  font-size: 4.4rem;
  color: #f9f9f9;
  text-align: center;
  margin-bottom: 2rem;
}

.footer-device-list {
  margin-top: 4rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  list-style: none;
}

.footer-device-item h1 {
  font-size: 2.6rem;
  color: #f9f9f9;
}

.footer-device-item p {
  font-size: 2rem;
  color: #c0c0c0;
  text-align: center;
  line-height: 3rem;
}

.footer-device-item img {
  width: 100%;
  margin: 2rem 0;
}

.last-p {
  margin-top: 3rem;
  font-size: 1.6rem;
  color: #c0c0c0;
  text-align: center;
}

/* ---------------------------------------- footer ---------------------------------------- */

footer {
  width: 100%;
  height: 25vh;
  margin-top: 5rem;
}

.footer-img {
  width: 90%;
  margin: 0 auto;
}

.footer-img img {
  width: 8rem;
  justify-content: center;
  position: relative;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.footer-links {
  width: 55%;
  margin: 0 auto 2rem;
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  font-size: 1.4rem;
  color: silver;
  display: inline-block;
  margin-bottom: 0;
  padding: 0.8rem 1.2rem;
  text-decoration: none;
  white-space: nowrap;
  justify-content: space-between;
}

footer p {
  font-size: 1.4rem;
  color: silver;
  line-height: 2rem;
  text-align: center;
}