*,
*::after,
*::before {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --clr-primary--one: #660874;
  --clr-primary--two: #D93379;

  --clr-neutral--one: hsl(229, 8%, 60%);
  --clr-neutral--two: hsl(229, 31%, 21%);

  --clr-primary--paper: #D5635F;
  --clr-primary--code: hsl(225, 2%, 35%);

}

html {
  font-size: 62.5%;
  
}

body {
  font-size: 18px;
  font-family: "Rubik", sans-serif;
}

html,
body {
  overflow-x: hidden;
}

.container {
  max-width: 1440px;
  width: 100%;
  margin: 0 auto;
}

img {
  max-width: 100%;
  display: block;
}

.bg-pattern {
  position: absolute;
  z-index: -1;
  opacity: 0.7;
}

h1 {
  color: var(--clr-neutral--two);
  font-size: 6rem;
  font-weight: 500;
}

h2 {
  font-weight: 500;
  font-size: 4rem;
  color: var(--clr-neutral--two);
}

p {
  color: var(--clr-neutral--one);
  max-width: 45ch;
  line-height: 1.6;
}

.btn {
  padding: 0.9em 2em;
  border-radius: 0.5rem;
  font-weight: 500;
  color: #fff;
  transition: all 0.3s;
  text-decoration: none;
  display: inline-block;
  box-shadow: 0 1rem 2rem rgba(0, 0, 0, 0.1);
  -webkit-border-radius: 0.5rem;
  -moz-border-radius: 0.5rem;
  -ms-border-radius: 0.5rem;
  -o-border-radius: 0.5rem;
  -webkit-transition: all 0.3s;
  -moz-transition: all 0.3s;
  -ms-transition: all 0.3s;
  -o-transition: all 0.3s;
}

.btnsmall {
  padding: 0.9em 2em;
  border-radius: 0.5rem;
  font-weight: 200;
  color: #fff;
  transition: all 0.3s;
  text-decoration: none;
  display: inline-block;
  box-shadow: 0 1rem 2rem rgba(0, 0, 0, 0.1);
  -webkit-border-radius: 0.5rem;
  -moz-border-radius: 0.5rem;
  -ms-border-radius: 0.5rem;
  -o-border-radius: 0.5rem;
  -webkit-transition: all 0.3s;
  -moz-transition: all 0.3s;
  -ms-transition: all 0.3s;
  -o-transition: all 0.3s;
}

.btn.clr1 {
  background-color: var(--clr-primary--two);
  border: 2px solid var(--clr-primary--two);
}

.btn.clr1:hover {
  color: var(--clr-primary--two);
  background-color: #fff;
}

.btn.clr2 {
  margin-top: 2rem;
  background-color: var(--clr-primary--one);
  border: 2px solid var(--clr-primary--one);
}

.btn.clr2:hover {
  margin-top: 2rem;
  color: var(--clr-primary--one);
  background-color: transparent;
}

.btn.clr3 {
  background-color: transparent;
  border: 2px solid transparent;
  color: var(--clr-neutral--one);
}

.btn.clr3:hover {
  border: 2px solid var(--clr-neutral--one);
}

.btnsmall.paper {
  margin-top: 2rem;
  background-color: var(--clr-primary--paper);
  border: 2px solid var(--clr-primary--paper);
}

.btnsmall.paper:hover {
  margin-top: 2rem;
  color: var(--clr-primary--paper);
  background-color: transparent;
}

.btnsmall.code {
  margin-top: 2rem;
  background-color: var(--clr-primary--code);
  border: 2px solid var(--clr-primary--code);
}

.btnsmall.code:hover {
  margin-top: 2rem;
  color: var(--clr-primary--code);
  background-color: transparent;
}

.flex {
  display: flex;
}

.section-heading {
  text-align: center;
}

.section-description {
  margin: 2.5rem auto;
  text-align: left;
}



header .container {
  position: relative;
}

header .bg-pattern {
  bottom: 5%;
  right: -55%;
  max-width: 130rem;
}

.navbar {
  justify-content: space-between;
  align-items: center;
  padding: 4rem 0;
}

.hamburger-container {
  display: none;
}

.nav-list {
  list-style: none;
  align-items: center;
}

.nav-list .social-media-list {
  display: none;
}

.nav-list .nav-item:not(:first-child) {
  margin-left: 5rem;
}

.nav-item .nav-link {
  text-decoration: none;
  text-transform: uppercase;
  font-size: 1.5rem;
  transition: all 0.3s;
  color: var(--clr-neutral--two);
  letter-spacing: 2px;
}

.nav-item .nav-link.btn {
  color: #fff;
}

.nav-item .nav-link:hover {
  color: var(--clr-primary--two);
}



.intro {
  padding: 1rem 0;
  align-items: center;
}

.intro-col-left {
  flex: 1;
  border-radius: 200px;
}


.intro-col-right {
  flex: 1;
  border-radius: 200px;
}

.intro-col-left h1 {
  font-size: 5rem;
}

.intro-col-left p {
  margin: 3rem 0 4rem 0;
}

.intro-col-left .btn-group .btn:nth-child(2) {
  margin-left: 1.5rem;
}



.feature {
  padding: 15rem 0;
}

.feature .container {
  position: relative;
}

.feature .bg-pattern {
  transform: rotateY(180deg);
  top: 58%;
  left: -42%;
  max-width: 110rem;
  -webkit-transform: rotateY(180deg);
  -moz-transform: rotateY(180deg);
  -ms-transform: rotateY(180deg);
  -o-transform: rotateY(180deg);
}

.tab-nav {
  justify-content: center;
  list-style: none;
  width: -moz-fit-content;
  width: -webkit-fit-content;
  width: fit-content;
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
  margin: 0 auto;
}

.tab-nav li {
  padding: 3rem 4rem;
  cursor: pointer;
  position: relative;
}

.tab-nav li:not(:last-child) {
  margin-right: 4rem;
}

.tab-nav li.active::before {
  content: "";
  position: absolute;
  width: 100%;
  height: 4px;
  background-color: var(--clr-primary--two);
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
}

.tab-body {
  align-items: center;
  justify-content: center;
  margin-top: 8rem;
  display: none;
  height: 40rem;
  animation: fadein 0.8s;
  -webkit-animation: fadein 0.8s;
}

@keyframes fadein {
  from {
    opacity: 0;
    transform: translateX(-2rem);
  }

  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.tab-body.active {
  display: flex;
}

.tab-body .tab-col-left,
.tab-body .tab-col-right {
  flex: 1;
}

.tab-body .tab-col-left img {
  margin: 0 auto;
}

.tab-col-right .content {
  width: -moz-fit-content;
  width: -webkit-fit-content;
  width: fit-content;
  margin: 0 auto;
}

.tab-col-right p {
  margin: 3rem 0 4rem;
}

.cards_row {
  padding: 10rem 0;
}

.browser-cards {
  margin: 8rem auto 0 auto;
  
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  width: 120rem;
  
  gap: 2rem;
  
}


.browser-cards .card {
  text-align: center;
  padding: 3rem 0;
  box-shadow: 0 1.5rem 2rem rgb(238, 238, 238);
  max-width: 35rem;
  border-radius: 1.5
}

.card img {
  margin: 0 auto;
  height: 200px;
}

.card h4 {
  color: var(--clr-neutral--two);
  font-size: 2.5rem;
  font-weight: 500;
  margin-top: 1rem;
}

.card p {
  margin-top: 1rem;
}



.faq {
  padding: 10rem 0;
}

.faq-container {
  width: 80%;
  margin: 8rem auto;
}

.question button {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 2.5rem 2rem 2.5rem 0;
  border: none;
  outline: none;
  background-color: transparent;
  cursor: pointer;
  color: var(--clr-neutral--two);
  font-size: 2rem;
  font-family: "Rubik", sans-serif;
  font-weight: 500;
  letter-spacing: 1px;
  transition: all 0.3s;
  text-align: left;
  -webkit-transition: all 0.3s;
  -moz-transition: all 0.3s;
  -ms-transition: all 0.3s;
  -o-transition: all 0.3s;
}

.faq-container .question {
  border-bottom: 1px solid var(--clr-neutral--one);
}

.faq-container .question:last-child {
  border-bottom: 1px solid var(--clr-neutral--one);
}

.faq-container .question:hover button {
  color: var(--clr-primary--two);
}

.question p {
  max-width: 100%;
  padding: 0;
  height: 0;
  overflow: hidden;
  transition: all 0.3s;
  opacity: 0;
  -webkit-transition: all 0.3s;
  -moz-transition: all 0.3s;
  -ms-transition: all 0.3s;
  -o-transition: all 0.3s;
}

.question button svg {
  transition: all 0.3s;
  min-width: 1.8rem;
  margin-left: 2rem;
  -webkit-transition: all 0.3s;
  -moz-transition: all 0.3s;
  -ms-transition: all 0.3s;
  -o-transition: all 0.3s;
}

.question.open button svg {
  transform: rotate(180deg);
  -webkit-transform: rotate(180deg);
  -moz-transform: rotate(180deg);
  -ms-transform: rotate(180deg);
  -o-transform: rotate(180deg);
}

.question.open button svg path {
  stroke: var(--clr-primary--two);
}

.question.open p {
  height: auto;
  opacity: 1;
  padding-bottom: 2.5rem;
}

.faq .center {
  text-align: center;
}



.subscribe {
  padding: 7rem 0;
  background-color: var(--clr-primary--one);
  text-align: center;
}

.subscribe .heading-sm {
  text-transform: uppercase;
  color: #fff;
  letter-spacing: 5px;
  font-size: 1.5rem;
}

.subscribe h2 {
  color: #fff;
  letter-spacing: 1px;
  margin: 4rem 0;
}

.subscribe .subscribe-form {
  justify-content: center;
}

.subscribe-form input {
  padding: 2rem;
  width: 35rem;
  border: none;
  outline: none;
  font-family: "Rubik", sans-serif;
  border-radius: 0.5rem;
  color: var(--clr-neutral--two);
  -webkit-border-radius: 0.5rem;
  -moz-border-radius: 0.5rem;
  -ms-border-radius: 0.5rem;
  -o-border-radius: 0.5rem;
}

.subscribe-form input::placeholder {
  color: var(--clr-neutral--one);
  font-size: 1.5rem;
  opacity: 0.7;
}

.subscribe-form .submit {
  font-family: "Rubik", sans-serif;
  font-size: 1.5rem;
  cursor: pointer;
  letter-spacing: 1px;
  margin-left: 1rem;
}



footer {
  background-color: var(--clr-neutral--two);
  padding: 3rem 0;
}

footer .container {
  justify-content: space-between;
  align-items: center;
}

.footer-nav .logo {
  margin-right: 6rem;
}

.footer-nav .logo svg path {
  fill: #fff;
}

.footer-nav,
.social-media-list {
  list-style: none;
}

.footer-nav .nav-item .nav-link {
  font-size: 1.3rem;
  color: #fff;
}

.footer-nav .nav-item .nav-link:hover {
  color: var(--clr-primary--two);
}

.footer-nav .nav-item:not(:last-child),
.social-media-list li:first-child {
  margin-right: 4rem;
}

.social-media-list svg path {
  transition: all 0.3s;
  -webkit-transition: all 0.3s;
  -moz-transition: all 0.3s;
  -ms-transition: all 0.3s;
  -o-transition: all 0.3s;
}

.social-media-list svg:hover path {
  fill: var(--clr-primary--two);
}



@media only screen and (min-width: 162.5em) {

  
  .bg-pattern {
    display: none;
  }
}

@media only screen and (max-width: 90em) {
  

  header .bg-pattern {
    right: -70%;
  }

  .feature .bg-pattern {
    left: -62rem;
  }
}

@media only screen and (max-width: 75em) {
  

  h1 {
    font-size: 5rem;
  }

  h2 {
    font-size: 3.5rem;
  }

  p {
    font-size: 1.7rem;
  }

  header .bg-pattern {
    right: -80%;
    max-width: 120rem;
  }

  .feature .bg-pattern {
    left: -68rem;
  }

  .tab-body .tab-col-left {
    margin-right: 2rem;
  }

  .browser-cards {
    grid-gap: 2rem;
  }
}

@media only screen and (max-width: 64em) {
  

  h1 {
    font-size: 4.5rem;
  }

  p {
    font-size: 1.6rem;
  }

  .btn {
    font-size: 1.7rem;
  }

  header .bg-pattern {
    right: -85%;
    max-width: 105rem;
  }

  .feature .bg-pattern {
    left: -72rem;
  }

  .faq-container {
    width: 70%;
  }
}

@media only screen and (max-width: 56.25em) {
  

  header .bg-pattern {
    right: -75%;
    max-width: 85rem;
  }

  h1 {
    font-size: 3.5rem;
  }

  h2 {
    font-size: 3rem;
  }

  p {
    font-size: 1.5rem;
    max-width: 35ch;
  }

  .btn {
    font-size: 1.4rem;
  }

  .feature .bg-pattern {
    top: 64%;
    left: -57rem;
    max-width: 85rem;
  }

  .tab-nav li {
    padding: 3rem;
  }
}

@media only screen and (max-width: 48em) {
  

  h1 {
    font-size: 5rem;
  }

  p {
    max-width: 50ch;
    font-size: 1.8rem;
  }

  .btn {
    font-size: 1.6rem;
  }

  header .bg-pattern {
    top: 25%;
    left: 20%;
    max-width: 115rem;
  }

  .navbar {
    padding: 4rem 2rem;
    z-index: 300;
    position: relative;
  }

  .navbar .nav-list {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background-color: hsla(229, 31%, 21%, 0.95);
    opacity: 0;
    pointer-events: none;
    z-index: 150;
    overflow-y: scroll;
    -webkit-overflow-scrolling: touch;
  }

  .nav-list.active {
    flex-direction: column;
    opacity: 1;
    padding: 0 4rem;
    pointer-events: all;
  }

  .nav-list .nav-item {
    width: 100%;
    text-align: center;
  }

  .nav-list .nav-item:not(:last-child) {
    margin-left: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    padding: 2.5rem 0;
  }

  .nav-list .nav-item:first-child {
    margin-top: 12rem;
  }

  .nav-list .nav-item .nav-link {
    color: #fff;
    font-size: 1.8rem;
    letter-spacing: 2px;
  }

  .nav-item .nav-link.btn {
    color: #fff;
    width: 100%;
    background-color: transparent;
    border: 2px solid #fff;
    padding: 0.8em 0;
    margin: 4rem auto;
  }

  .nav-list .social-media-list {
    display: flex;
    margin: auto 0 6rem;
  }

  .logo-container {
    z-index: 999999;
  }

  .logo-container svg circle,
  .logo-container svg circle+path,
  .logo-container svg path {
    transition: all 0.3s;
  }

  .logo-container.active svg circle,
  .logo-container.active svg path {
    fill: #fff;
  }

  .logo-container.active svg circle+path {
    fill: #000;
  }

  .hamburger-container {
    display: block;
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    right: 2rem;
    z-index: 200;
    -webkit-transform: translateY(-50%);
    -moz-transform: translateY(-50%);
    -ms-transform: translateY(-50%);
    -o-transform: translateY(-50%);
  }

  .hamburger-container img {
    width: 3.5rem;
  }

  .intro {
    flex-direction: column;
    padding: 5rem 0;
  }

  .intro-col-left {
    order: 2;
    text-align: center;
    margin-top: 15rem;
  }

  .feature {
    padding: 8rem 0;
  }

  .feature .bg-pattern {
    top: 50%;
    left: -54rem;
    max-width: 100rem;
  }

  .tab-container {
    margin-top: 6rem;
  }

  .tab-nav {
    flex-direction: column;
    align-items: center;
    width: 100%;
    text-align: center;
    border: none;
  }

  .tab-nav li:not(:last-child) {
    margin-right: 0;
  }

  .tab-nav li {
    width: 90%;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
  }

  .tab-nav li:last-child {
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
  }

  .tab-nav li.active::before {
    width: 50%;
  }

  .tab-body {
    flex-direction: column;
    text-align: center;
    width: auto;
  }

  .tab-body .tab-col-right {
    margin-top: 10rem;
  }

  .tab-body .tab-col-left {
    margin-right: 0;
  }

  .browser-cards {
    grid-template-columns: 1fr;
    grid-gap: 3rem;
  }

  .browser-cards .card {
    margin: 0 auto;
    width: 100%;
  }

  .browser-cards .card:nth-child(2),
  .browser-cards .card:nth-child(3) {
    transform: none;
    -webkit-transform: none;
    -moz-transform: none;
    -ms-transform: none;
    -o-transform: none;
  }

  .faq-container {
    width: 90%;
  }

  .subscribe .subscribe-form {
    flex-direction: column;
  }

  .subscribe-form input {
    width: 70%;
    margin: 0 auto;
  }

  .subscribe-form .submit {
    width: 70%;
    margin: 1.5rem auto;
  }

  footer .container,
  .footer-nav {
    flex-direction: column;
  }

  .footer-nav {
    align-items: center;
    margin: 0 0 3rem 0;
  }

  .footer-nav .logo {
    margin: 0 0 4rem 0;
  }

  .footer-nav .nav-item .nav-link {
    font-size: 1.8rem;
  }

  .footer-nav .nav-item:not(:last-child) {
    margin-right: 0;
    margin-bottom: 4rem;
  }

  footer .social-media-list {
    margin-top: 3rem;
  }
}

@media only screen and (max-width: 36em) {
  

  h1 {
    font-size: 4rem;
  }

  p {
    max-width: 45ch;
    font-size: 1.6rem;
  }

  header .bg-pattern {
    top: 23%;
    right: -55%;
    max-width: 100rem;
  }

  .feature .bg-pattern {
    top: 50%;
    left: -58rem;
    max-width: 100rem;
  }

  .faq-container {
    width: 95%;
  }

  .question button {
    font-size: 1.8rem;
  }
}

@media only screen and (max-width: 30em) {
  

  h1 {
    font-size: 3.5rem;
  }

  h2 {
    font-size: 2.5rem;
  }

  .btn {
    font-size: 1.3rem;
  }

  header .bg-pattern {
    top: 27%;
    right: -55%;
    max-width: 70rem;
  }

  .hamburger-container img {
    width: 3rem;
  }

  .intro-col-left {
    margin-top: 8rem;
  }

  .feature .bg-pattern {
    top: 52%;
    left: -55rem;
    max-width: 82rem;
  }

  .question button {
    font-size: 1.6rem;
  }

  .subscribe h2 br {
    display: none;
  }

  .footer-nav .nav-item .nav-link {
    font-size: 1.6rem;
  }
}

@media only screen and (max-width: 22em) {
  

  h1 {
    font-size: 2.8rem;
    padding: 0;
  }

  p {
    font-size: 1.4rem;
  }

  header .bg-pattern {
    top: 22%;
    right: -55%;
    max-width: 60rem;
  }

  .hamburger-container img {
    width: 2.5rem;
  }

  .intro-col-left {
    margin-top: 8rem;
  }

  .intro .btn {
    max-width: 200px;
    display: block;
    margin: 0 auto;
  }

  .intro-col-left .btn-group .btn:nth-child(2) {
    margin: 2rem auto 0;
  }

  .feature .bg-pattern {
    top: 55%;
    left: -35rem;
    max-width: 60rem;
  }

  .tab-nav li {
    width: 100%;
    font-size: 1.6rem;
  }

  .subscribe-form input,
  .subscribe-form .submit {
    width: 100%;
  }
}


.attribution {
  padding: 1rem 0;
  background-color: #272727;
}

.attribution p {
  max-width: 100%;
  text-align: center;
  color: #fff;
}

.attribution a {
  text-decoration: none;
  color: #ff7a00;
}

.paper-list {
  padding: 50px 0;
}

.paper-list .btn {
  display: inline-block;
  margin-bottom: 30px;
}

.section-heading {
  font-size: 2em;
  margin-bottom: 20px;
}


.faq {
  padding: 50px 0;
}

.question {
  margin-bottom: 20px;
}

html {
  scroll-behavior: smooth;
}

.btnsmall {
  display: inline-flex; 
  align-items: center; 
  text-decoration: none; 
  padding: 5px 10px; 
  border: 1px solid #ccc; 
  border-radius: 5px; 
}

.btnsmall .icon img {
  width: 20px; 
  height: auto; 
  margin-right: 5px; 
  transition: opacity 0.3s ease; 
}

.btnsmall.paper:hover .icon img {
  content: url('images/pdf.png'); 
}

.btnsmall.code:hover .icon img {
  content: url('images/github.png'); 
}
/* 自定义DataTables样式
.dataTables_wrapper .dataTables_filter {
  float: right;
  text-align: right;
}

.dataTables_wrapper .dataTables_length {
  float: left;
}

.dataTables_wrapper .dataTables_paginate {
  float: right;
  text-align: right;
}

.dataTables_wrapper .dataTables_info {
  float: left;
  padding-top: 8px;
}

.dataTables_wrapper .dataTables_processing {
  background-color: #f3f3f3;
  border: 1px solid #ddd;
  padding: 10px;
} */