/* mobile 375px */
/* desktop 1440px */

:root {
  /* primary colours */
  --clr-prm-dark-blue: hsl(233, 26%, 24%);
  --clr-prm-lime: hsl(136, 65%, 51%);
  --clr-prm-bright-cyan: hsl(192, 70%, 51%);

  /* neutral colours */
  --clr-ntr-gray-blue: hsl(233, 8%, 62%);
  --clr-ntr-light-gray-blue: hsl(220, 16%, 96%);
  --clr-ntr-very-light-gray: hsl(0, 0%, 98%);
  --clr-ntr-white: hsl(0, 0%, 100%);

  /* body font size */
  --fs-body: 18px;

  /* primary gradient */
  --gradient-prm: linear-gradient(90deg, var(--clr-prm-lime), var(--clr-prm-bright-cyan));
}

/* general setting */

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

body, 
h1, 
h2, 
h3, 
h4, 
h5, 
h6, 
p, 
picture {
  margin: 0;
  padding: 0;
}

html {
  font-family: 'Public Sans', sans-serif;
}

body {
  font-size: var(--fs-body);
}

/* site layout */

.main-background-wrapper {
  overflow-x: hidden;
}

.center-layout {
  padding-inline: 11.5%;
}

.mobile {
  display: none;
}

/* header */

.header-main {
  position: relative;
  z-index: 1;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-block: 1em;
}

.nav-desktop {
  display: flex;
  justify-content: space-between;
  gap: 1em;

  font-size: 0.8em;
}

.nav-desktop-item {
  position: relative;
  text-decoration: none;
  color: inherit;
}

.nav-desktop-item:hover {
  color: var(--clr-prm-dark-blue);
}

.nav-desktop-item::before {
  content: "";
  opacity: 0;

  position: absolute;
  bottom: calc(-16px + -1em);
  width: 100%;
  height: 4px;
  
  background-image: var(--gradient-prm);

  transition: opacity 100ms linear;
}

.nav-desktop-item:hover::before {
  opacity: 1;
}

/* intro section */

.intro-section {
  position: relative;
  display: grid;
  grid-template-columns: 50% 50%;
}

.intro-title {
  margin-bottom: 2rem;
  font-size: 3em;
}

.intro-text-container {
  padding-top: 9em;
  padding-right: 5em;
  padding-bottom: calc(12.5em + 2px);
}

.intro-text {
  margin-bottom: 2.5rem;
}

.intro-img-container {
  position: relative;
}

.intro-bg-img-desktop {
  position: absolute;
  top: -265px;
  left: -110px;
}

.intro-phones-img {
  position: absolute;
  top: -120px;
  left: 80px;
}

/* usps section */

.usps-section {
  padding-block: 6em;
}

.usps-intro-container {
  margin-bottom: 4em;
}

.usps-intro-title {
  margin-bottom: 1.5rem;
  font-size: 2em;
}

.usps-container {
  display: flex;
  justify-content: space-between;
  gap: 1em;
}

.usp-icon {
  margin-bottom: 1em;
}

.usp-single-container {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1.5em;
  max-width: 260px;
}

.usp-title {
  font-size: 1.25em;
}

.usp-text {
  font-size: 0.9em;
}

/* articles section */

.articles-section {
  padding-block: 6em;
}

.articles-title {
  font-size: 2em;
  margin-bottom: 1.5em;
}

.articles-container {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2em;
}

.article-single-container {
  border-radius: 5px;
}

.article-image {
  width: 100%;
  max-width: 255px;
  height: 200px;
  border-radius: 5px 5px 0 0;
}

.article-link {
  text-decoration: none;
}

.article-link:hover .article-title {
  color: var(--clr-prm-lime);
}

.article-info {
  display: flex;
  flex-direction: column;
  gap: 0.75em;
  padding: 1.5em 1em 0.5em;
}

.article-author {
  font-size: 0.5em;
}

.article-title {
  font-size: 0.9em;
}

.article-text {
  font-size: 0.75em;
}

/* footer */

.footer-main {
  position: relative;
  display: flex;
  gap: 7.5em;
  padding-block: 2.5em 4em;
}

.footer-socials-container {
  display: flex;
  justify-content: space-between;
  gap: 0.75em;
  margin-top: 3em;
}

.footer-social-icon {
  cursor: pointer;
}

.footer-social-icon:hover path {
  fill: var(--clr-prm-lime);
}

.nav-footer {
  display: flex;
  justify-content: space-between;
  width: 29%;
}

.nav-footer-column {
  display: flex;
  flex-direction: column;
  gap: 1em;
}

.nav-footer-link {
  font-size: 0.75em;
  text-decoration: none;
}

.nav-footer-link:hover {
  color: var(--clr-prm-lime);
}

.footer-button-copyright-container {
  margin-left: auto;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 1.5em;
}

.footer-copyright {
  font-size: 0.8em;
}

.attribution {
  position: absolute;
  bottom: 10px;
  left: 50%;
  transform: translateX(-50%);

  font-size: 0.8em;
  color: var(--clr-ntr-white);
}

.attribution a {
  color: inherit;
}

@media screen and (max-width: 1280px) {
  .center-layout {
    padding-inline: 5%;
  }
}

@media screen and (max-width: 1000px) {

  .usps-container {
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: space-around;
    row-gap: 2em;
  }

  .articles-container {
    grid-template-columns: 1fr 1fr;
    column-gap: 6em;
  }

  .article-image {
    max-width: unset;
  }
}

@media screen and (max-width: 800px) {
  /* general layout and settings */

  .center-layout {
    padding-inline: 1.5em;
  }

  .desktop {
    display: none;
  }

  .mobile {
    display: unset;
  }

  .main-container {
    padding-top: 56px;
    overflow: auto;
  }

  /* header */

  .header-main {
    position: fixed;
    z-index: 2;
    top: 0;
    left: 0;
    width: 100%;
  }

  /* navigation mobile */

  .nav-mobile {
    position: fixed;
    z-index: 1;
    top: 4em;
    left: 50%;
    transform: translateX(-50%);

    padding-block: 1em;
    width: 90%;

    text-align: center;
    border-radius: 5px;
  }

  .nav-mobile-item {
    display: block;
    padding-block: 0.65em;
    text-decoration: none;
  }

  .nav-mobile-overlay {
    position: fixed;
    z-index: 1;
    width: 100%;
    height: 100vh;
    background-color: var(--clr-prm-dark-blue);
    opacity: 0.4;
  }

  /* intro sectiom */

  .intro-section {
    grid-template-columns: 1fr;
    
  }

  .intro-text-container {
    grid-row: 2 / 3;
  }

  .intro-img-container {
    grid-row: 1 / 2;
    height: 200px;
  }

  .intro-bg-img-mobile {
    position: absolute;
    top: -50px;
    left: 0;
    width: 100%;
    height: 423px;
  }

  .intro-phones-img {
    top: -124px;
    left: 50%;
    transform-origin: 0% 0%;
    transform: translateX(-50%);
    scale: 0.45;
  }

  .intro-text-container {
    padding-top: 7em;
    padding-bottom: 5em;
    padding-right: unset;
    text-align: center;
  }

  .intro-title {
    font-size: 2.25em;
    margin-bottom: 1rem;
  }

  .intro-text {
    font-size: 0.825em;
  }

  /* usps section /*/

  .usps-section {
    padding-block: 4em;
    text-align: center;
  }

  .usps-intro-container {
    margin-bottom: 3em;
  }

  .usps-intro-title {
    font-size: 1.75em;
  }

  .usps-intro-text {
    font-size: 0.85em;
  }

  .usp-single-container {
    align-items: center;
  }

  .usp-icon {
    margin-bottom: unset;
  }

  .usp-text {
    width: 320px;
    font-size: 0.85em;
  }

  /* articles section */

  .articles-section {
    padding-block: 5em;
  }

  .articles-title {
    margin-bottom: 1em;
    text-align: center;
  }

  .articles-container {
    gap: 1em;
  }

  .article-image {
    max-width: unset;
    max-height: 200px;
  }

  .article-info {
    padding: 1.5em;
    gap: 0.5em;
  }

  .article-text {
    font-size: 0.7em
  }

  /* footer */

  .footer-main {
    display: block;
    text-align: center;
    padding-inline: 4em;
  }

  .footer-logos-container {
    margin-bottom: 2em;
  }

  .footer-socials-container {
    margin-top: 1.5em;
    gap: unset;
  }

  .footer-social-icon {
    scale: 1.25;
  }

  .nav-footer {
    display: block;
    width: unset;
    margin-bottom: 2em;
  }

  .nav-footer-column:last-child {
    margin-top: 1em;
  }

  .footer-button-copyright-container {
    align-items: center;
  }

  .attribution {
    min-width: 250px;
  }

}

@media screen and (max-width: 700px) {
  .usps-container {
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    gap: 2em;
  }
}

@media screen and (max-width: 500px) {
  .articles-container {
    grid-template-columns: 1fr;
  }
}


/* utility classes */

/* paragraphs */

p {
  line-height: 1.5em;
}

/* buttons */

button, 
.button {
  padding: 1em 3em;
  
  color: var(--clr-ntr-white);
  background-image: var(--gradient-prm);

  border: none;
  border-radius: 100vw;

  cursor: pointer;
  font-family: 'Public Sans', sans-serif;
}

button:hover, 
.button:hover {
  opacity: 0.7;
}

/* font weights */

.fw-light { font-weight: 300; }
.fw-normal { font-weight: 400; }
.fw-bold { font-weight: 700; }

/* text colours */

.tc-light { color: var(--clr-ntr-gray-blue); }
.tc-dark { color: var(--clr-prm-dark-blue); }
.tc-white { color: var(--clr-ntr-white); }

/* background-colours */

.bgc-white { background-color: var(--clr-ntr-white); }
.bgc-gray { background-color: var(--clr-ntr-very-light-gray); }
.bgc-dark-gray { background-color: var(--clr-ntr-light-gray-blue); }
.bgc-very-dark { background-color: var(--clr-prm-dark-blue); }

/* hide elements */

.hidden { display: none; }