/*=============== GOOGLE FONTS ===============*/
@import url("https://fonts.googleapis.com/css2?family=Montserrat:wght@100..900&display=swap");

/*=============== VARIABLES CSS ===============*/
:root {
  --header-height: 3.5rem;

  /*========== Colors ==========*/
  /*Color mode HSL(hue, saturation, lightness)*/
  --first-color: hsl(202, 95%, 55%);
  --second-color: hsl(147, 53%, 38%);
  --first-gradient: linear-gradient(90deg,
                  hsl(212, 95%, 55%),
                  hsl(140, 83%, 33%));
  --title-color: hsl(255, 12%, 12%);
  --text-color: hsl(225, 12%, 24%);
  --text-color-light: hsl(255, 4%, 70%);
  --body-color: hsl(0, 0%, 100%);
  --container-color: hsl(0, 0%, 100%);
  --white-color: hsl(0, 0%, 100%);
  --black-color: hsl(255, 20%, 10%);
  --gray-border: hsl(255, 6%, 90%);
  --black-border: hsl(255, 10%, 20%);

  /*========== Font and typography ==========*/
  /*.5rem = 8px | 1rem = 16px ...*/
  --body-font: "Montserrat", sans-serif;
  --big-font-size: 2.25rem;
  --h1-font-size: 1.5rem;
  --h2-font-size: 1.25rem;
  --h3-font-size: 1rem;
  --normal-font-size: .938rem;
  --small-font-size: .813rem;

  /*========== Font weight ==========*/
  --font-regular: 400;
  --font-medium: 500;
  --font-semi-bold: 600;
  --font-bold: 700;

  /*========== z index ==========*/
  --z-tooltip: 10;
  --z-fixed: 100;
}

/*========== Responsive typography ==========*/
@media screen and (min-width: 1150px) {
  :root {
    --big-font-size: 3.5rem;
    --h1-font-size: 2.25rem;
    --h2-font-size: 1.5rem;
    --h3-font-size: 1.25rem;
    --normal-font-size: 1rem;
    --small-font-size: .875rem;
  }
}

/*=============== BASE ===============*/
* {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--body-font);
  font-size: var(--normal-font-size);
  background-color: var(--body-color);
  color: var(--text-color);
}

h1, h2, h3, h4 {
  color: var(--title-color);
  font-weight: var(--font-semi-bold);
}

ul {
  list-style: none;
}

a {
  text-decoration: none;
}

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

/*=============== REUSABLE CSS CLASSES ===============*/
.container {
  max-width: 1120px;
  margin-inline: 1.5rem;
}

.grid {
  display: grid;
  gap: 1.5rem;
}

.section {
  padding-block: 5rem 1rem;
}
.section__title, 
.section__subtitle {
  text-align: left;
}

.section__title {
  font-size: var(--h1-font-size);
  font-weight: var(--font-bold);
  margin-bottom: .5rem;
  text-align: left;
}

.section__subtitle {
  display: block;
  font-size: var(--normal-font-size);
  font-weight: var(--font-semi-bold);
  color: var(--second-color);
  margin-bottom: .5rem;
}

.main {
  overflow: hidden;
}

/*=============== HEADER & NAV ===============*/
.header{
  position: fixed;
  width: 100%;
  top: 0;
  left: 0;
  background-color: transparent;
  z-index: var(--z-fixed);
  transition: background-color .4s;
}

.nav{
  position: relative;
  height: var(--header-height);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav__logo{
  display: flex;
  align-items: center;
  column-gap: .25rem;
}

.nav__logo span{
  color: var(--white-color);
  font-weight: var(--font-semi-bold);
  transition: color .4s;
}

.nav__logo i{
  color: var(--first-color);
  font-size: 1.5rem;
}

.nav__toggle,
.nav__close{
  font-size: 1.5rem;
  color: var(--white-color);
  cursor: pointer;
  transition: color .4s;
}

/* Navigation for mobile devices */
@media screen and (max-width: 1150px) {
  .nav__menu{
    position: fixed;
    top: 0;
    right: -100%;
    background-color: var(--black-color);
    width: 80%;
    height: 100%;
    padding: 7.5rem 3.5rem 0;
    border-left: 2px solid var(--black-border);
    transition: right .4s;
  }
}

.nav__list{
  display: flex;
  flex-direction: column;
  row-gap: 4rem;
}

.nav__link{
  color: var(--text-color-light);
  font-weight: var(--font-semi-bold);
  transition: color .4s;
}

.nav__link:hover{
  color: var(--first-color);
}

.nav__close{
  position: absolute;
  top: 1rem;
  right: 1.5rem;
}

/* Show menu */
.show-menu{
  right: 0;
}

/* Change background header */
.bg-header{
  background-color: var(--body-color);
  box-shadow: 0 4px 16px hsla(255, 90%, 8%, .1);
}

.bg-header .nav__logo span,
.bg-header .nav__toggle{
  color: var(--title-color);
}

/* Active link */
.active-link{
  color: var(--first-color);
}

/*=============== HOME ===============*/
.home{
  position: relative;
  background-color: var(--black-color);
}

.home__container{
  position: relative;
  row-gap: 3rem;
  padding-block: 2.5rem 6rem;
}

.home__content{
  row-gap: 2.5rem;
}

.home__data{
  text-align: center;
}

.home__title{
  color: var(--white-color);
  font-size: var(--big-font-size);
  font-weight: var(--font-bold);
  margin-bottom: 1rem;
}

.home__description{
  text-align: justify;        
  line-height: 1.5; 
  color: var(--text-color-light);
}

.home__images{
  position: relative;
  justify-self: center;
}

.home__img-1{
  width: 250px;
  margin-top: 1.5rem;
}

.home__lines{
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: right;
}

/*=============== BUTTON ===============*/
.button{
  display: inline-flex;
  background: var(--first-gradient);
  color: var(--white-color);
  font-weight: var(--font-semi-bold);
  padding: 1rem 2rem;
  transition: box-shadow .4s;
}

.button:hover{
  box-shadow: 0 8px 32px hsla(18, 95%, 55%, .3);
  color: var(--white-color);
}

.button__link{
  display: flex;
  align-items: center;
  column-gap: .25rem;
  color: var(--first-color);
}

.button__link span{
  font-weight: var(--font-semi-bold);
}

.button__link i{
  font-size: 1.5rem;
  transition: transform .4s;
}

.button__link:hover i{
  transform: translateX(.25rem);
}


/*=============== ABOUT ===============*/
.about{
  row-gap: 8rem;
}

.about__data{
  text-align: center;
}

.about__description{
  margin-bottom: 2rem;
}

.about__list{
  text-align: initial;
  grid-template-columns: repeat(2, 130px);
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 2.5rem;
}

.about__list-item{
  display: flex;
  column-gap: .5rem;
  color: var(--title-color);
}

.about__list-item i{
  font-size: 1.25rem;
  color: var(--first-color);
}

.about__images{
  position: relative;
  justify-self: center;
}

.about__img-1{
  width: 200px;
  border: 5px solid var(--body-color);
  position: absolute;
  left: 6rem;
}

.about__img-2{
  width: 250px;
}



/* Swiper class */
.swiper{
  margin-inline: initial;
  padding-bottom: 3rem;
}

.swiper-button-prev::after,
.swiper-button-next::after{
  content: '';
}

.swiper-button-prev,
.swiper-button-next{
  top: initial;
  bottom: 0;
  width: 32px;
  height: 32px;
  background-color: var(--container-color);
  box-shadow: 0 2px 8px hsla(255, 8%, 4% .1);
  border-radius: 50%;
  font-size: 1.5rem;
  color: var(--title-color);
}

.swiper-button-prev{
  left: calc(50% - 3rem);
}
.swiper-button-next{
  right: calc(50% - 3rem);
}

/*=============== ARTICLE ===============*/
.article__year {
  font-size: 0.9rem;
  color: #666;
  margin-bottom: 0.5rem;
}

.article__title {
  font-size: 1.1rem;
  font-weight: bold;
  margin-bottom: 0.5rem;
  text-align: left;
}

.article__info {
  font-size: 0.95rem;
  color: #333;
  margin-bottom: 0.75rem;
}

.article__card{
  background-color: var(--container-color);
  border: 2px solid var(--gray-border);
  padding: 1.5rem 2rem;
  text-align: left;
  transition: border-color .4s;
}

.article__card:hover{
  border-color: var(--first-color);
}

/*=============== CONTACT ===============*/
.contact__container{
  row-gap: 3rem;
  padding-block: 1.5rem 3rem;
  width: 350px;
  height: 350px;
  margin-left: 4rem;
}

.contact__data{

  justify-content: center;
  row-gap: 1.5rem;
}

.contact__card{
  background-color: var(--container-color);
  border: 2px solid var(--gray-border);
  padding: 1.5rem 2rem;
  text-align: center;
  transition: border-color .4s;
  margin-left: 1rem;
}

.contact__card:hover{
  border-color: var(--first-color);
}

.contact__icon{
  width: 48px;
  height: 48px;
  background-color: var(--black-color);
  color: var(--white-color);
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 2rem;
  margin: 0 auto 1.25rem;
}

.contact__title{
  font-size: var(--h2-font-size);
  margin-bottom: .5rem;
}

.contact__info{
  font-style: normal;
}

.contact__social{
  display: flex;
  justify-content: center;
  column-gap: 1rem;
}

.contact__social-link{
  font-size: 1.5rem;
  color: var(--first-color);
  transition: transform .4s;
}

.contact__social-link:hover{
  transform: translateY(-.25rem);
}

/*=============== FOOTER ===============*/
.footer{
  background-color: var(--black-color);
  color: var(--text-color-light);
  padding-block: 3.5rem 2rem;
}

.footer__container{
  row-gap: 4rem;
  padding-bottom: 4rem;
  border-bottom: 1px solid var(--black-border);
}

.footer__logo{
  display: inline-flex;
  align-items: center;
  column-gap: .25rem;
}

.footer__logo span{
  color: var(--white-color);
  font-size: var(--h3-font-size);
  font-weight: var(--font-semi-bold);
}

.footer__logo i{
  color: var(--first-color);
  font-size: 1.5rem;
}

.footer__description{
  margin-block: 1rem;
}

.footer__email,
.footer__info{
  font-style: normal;
}

.footer__content{
  grid-template-columns: repeat(2, max-content);
  gap: 4rem 3rem;
}

.footer__title{
  font-size: var(--h3-font-size);
  color: var(--white-color);
  margin-bottom: 1rem;
}

.footer__links,
.footer__list{
  display: grid;
  row-gap: .5rem;
}

.footer__link{
  color: var(--text-color-light);
  transition: color .4s;
}

.footer__link:hover{
  color: var(--first-color);
}

.footer__social{
  display: flex;
  column-gap: 1rem;
}

.footer__social-link{
  font-size: 1.5rem;
  color: var(--first-color);
  transition: transform .4s;
}

.footer__social-link:hover{
  transform: translateY(-.25rem);
}

.footer__copy{
  display: block;
  text-align: center;
  font-size: var(--small-font-size);
  margin-top: 4rem;
}

/*=============== SCROLL BAR ===============*/
::-webkit-scrollbar{
  width: .6rem;
  background-color: hsl(255, 5%, 75%);
}

::-webkit-scrollbar-thumb{
  background-color: hsl(255, 5%, 65%);
}

::-webkit-scrollbar-thumb:hover{
  background-color: hsl(255, 5%, 55%);
}

/*=============== SCROLL UP ===============*/
.scrollup{
  position: fixed;
  right: 1rem;
  bottom: -50%;
  background-color: var(--body-color);
  box-shadow: 0 4px 16px hsla(255, 90%, 8%, .15);
  color: var(--title-color);
  display: inline-flex;
  font-size: 1.25rem;
  z-index: var(--z-tooltip);
  transition: bottom .4s, transform .4s;
}

.scrollup:hover{
  transform: translateY(-.5rem);
}

/* Show Scroll Up */
.show-scroll{
  bottom: 3rem;
}

/*=============== BREAKPOINTS ===============*/
/* For small devices */
@media screen and (max-width: 340px){
  .container{
    margin-inline: 1rem;
  }

  .home__description{
    text-align: justify;       
    line-height: 1.5;  
  }
  
  .section__title{
    font-size: 1.25rem;
    text-align: left;
  }

  .home__title{
    font-size: 1.75rem;
  }

  .home__buttons{
    flex-direction: column;
  }

  .home__img-1{
    width: 250px;
    margin-left: 0rem;
  }

  .article__card{
  background-color: var(--container-color);
  border: 2px solid var(--gray-border);
  padding: 1.5rem 2rem;
  text-align: left;
  transition: border-color .4s;
  }

.article__card:hover{
  border-color: var(--first-color);
}

  .about__list{
    grid-template-columns: repeat(1, 200px);
  }

  .footer__content{
    grid-template-columns: repeat(1, max-content);
  }
}

/* For medium devices */
@media screen and (min-width: 540px){
  .home__container,
  .about__container,
  .services__container,
  .projects__container,
  .contact__container{
    grid-template-columns: 360;
    justify-content: center;
  }

  .home__description{
    text-align: justify;       
    line-height: 1.5;  
  }

  .home__img-1{
    width: 250px;
    margin-left: 0rem;
  }

  .article__card{
  background-color: var(--container-color);
  border: 2px solid var(--gray-border);
  padding: 1.5rem 2rem;
  text-align: left;
  transition: border-color .4s;
  }

  .article__card:hover{
  border-color: var(--first-color);
  }

  .footer__content{
    grid-template-columns: repeat(3, max-content);
  }
}

@media screen and (min-width: 768px) {

  .nav__menu{
    width: 50%;
  }

  .home__description{
    text-align: justify;       
    line-height: 1.5;  
  }

  .home__img-1{
    width: 250px;
    margin-left: 0rem;
  }

  .article__card{
  background-color: var(--container-color);
  border: 2px solid var(--gray-border);
  padding: 1.5rem 2rem;
  text-align: left;
  transition: border-color .4s;
  }

  .article__card:hover{
  border-color: var(--first-color);
  }

  .contact__data{
    grid-template-columns: repeat(3, 350px);
  }

  .footer__container{
    grid-template-columns: repeat(2, max-content);
    justify-content: space-between;
  }
}

/* For large devices */
@media screen and (min-width: 1150px){
  .container{
    margin-inline: auto;
  }  

  .section{
    padding-block: 7rem 2rem;
  }

  .nav{
    height: calc(var(--header-height) + 2rem);
  }

  .nav__toggle,
  .nav__close{
    display: none;
  }

  .nav__menu{
    width: initial;
  }

  .nav__list{
    flex-direction: row;
    align-items: center;
    column-gap: 4rem;
  }

  .bg-header .nav__link{
    color: var(--text-color);
  }

  .bg-header .active-link,
  .bg-header .nav__link:hover{
    color: var(--first-color);
  }

  .bg-header .button,
  .bg-header .button:hover{
    color: var(--white-color);
  }

  .home__container{
    grid-template-columns: 775px 250px;
    align-items: flex-start;
  }

  .home__content{
    row-gap: 4.5rem;
  }

  .home__data{
    text-align: initial;
  }

  .home__description{
    text-align: justify;       
    line-height: 1.5;  
  }

  .home__img-1{
    width: 250px;
  }

 
  .home__lines{
    object-position: center;
  }

  .about__container{
    grid-template-columns: repeat(2, 480px);
    column-gap: 9rem;
  }

  .about__images{
    order: -1;
  }

  .swiper-button-next,
  .swiper-button-prev{
    bottom: 3rem;
  }

  .article__card{
  background-color: var(--container-color);
  border: 2px solid var(--gray-border);
  padding: 1.5rem 2rem;
  text-align: left;
  transition: border-color .4s;
  }

  .article__card:hover{
  border-color: var(--first-color);
  }

  .contact :is(.section__title, .section__subtitle){
    text-align: initial;
  }

  .contact__container{
    grid-template-columns: 530px 515px;
    justify-items: initial;
    align-items: flex-start;
    column-gap: 3.5rem;
    padding-block: 3.5rem 4rem;
  }

  .contact__img{
    width: 530px;
  }

  .contact__data{
    gap: 1rem;
  }

  .contact__card{
    border-width: 1px;
  }

  .contact__title{
    font-size: var(--h3-font-size);
  }

  .footer{
    padding-block: 3rem 3rem;
  }

  .footer__container{
    padding-bottom: 3rem;
  }

  .footer__content{
    column-gap: 7rem;
  }

  .footer__description{
    margin-block: 1.5rem;
  }

  .footer__title{
    margin-bottom: 1.5rem;
  }

  .footer__links,
  .footer__list{
    row-gap: 1rem;
  }

  .scrollup{
    right: 3rem;
  }
}


.researcher__link{
  color: var(--second-color);
  text-size-adjust: var(--font-bold);
}

.researcher__link:hover{
  color: var(--first-color);
}


.button2{
  display: inline-flex;
  background: var(--first-gradient);
  color: var(--white-color);
  font-weight: var(--font-semi-bold);
  padding: 0.5rem 1rem;
  transition: box-shadow .4s;
  margin-top: .5rem;
}

.button2:hover{
  box-shadow: 0 8px 32px hsla(18, 95%, 55%, .3);
  color: var(--white-color);
}

.button2__link{
  display: flex;
  align-items: center;
  column-gap: .25rem;
  color: var(--first-color);
}

.button2__link span{
  font-weight: var(--font-semi-bold);
}

.button2__link i{
  font-size: 1.5rem;
  transition: transform .4s;
}

.button2__link:hover i{
  transform: translateX(.25rem);
}