:root {
  color-scheme: light dark;

  --base-color: hsl(220, 23.1%, 94.9%);
  --base-color-text: hsl(0, 0%, 2.7%);
  --base-color-text-title: hsl(0, 0%, 2.7%);

  --primary-color: hsl(201.6, 45.1%, 40%);
  --primary-color-text: hsl(0, 0%, 100%, 0.9);

  --navbar-link-color: hsl(0, 0%, 2.7%);
  --navbar-link-active-color: hsl(201.6, 45.1%, 40%);

  --base-shadow: 0 0 4px hsl(0, 0%, 0%, 0.2);
  --background-color: hsl(225.7, 33.3%, 87.6%);
  --navbar-background-color: hsl(220, 23%, 100%);
  --footer-color: var(--base-color-text);
  --footer-background-color: var(--navbar-background-color);

  --button-background-color: hsl(0, 0%, 100%);

  --default-font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Oxygen-Sans, Ubuntu, Cantarell, sans-serif;
  --header-font-family: Roboto, sans-serif;
}

.nav-logo.dark-logo {
  display: none;
}

@media (prefers-color-scheme: dark) {
  :root {
    --base-color: hsl(210, 9.3%, 21.2%);
    --base-color-text: hsl(0, 0%, 100%, 0.9);
    --base-color-text-title: hsl(0, 0%, 100%, 0.9);

    --navbar-link-color: hsl(0, 0%, 100%, 0.9);
    --navbar-link-active-color: hsl(201.6, 45.1%, 70%);

    --base-shadow: 0 0 4px hsl(0, 0%, 0%, 0.4);
    --background-color: hsl(210, 9.3%, 21.2%);
    --navbar-background-color: hsl(210, 9.3%, 28.2%);
    --footer-color: var(--base-color-text);
    --footer-background-color: var(--navbar-background-color);

    --button-background-color: hsl(210, 5%, 21%);
  }

  .nav-logo {
    display: none;
  }

  .nav-logo.dark-logo {
    display: initial;
  }

  #toggle-nav-btn {
    filter: invert(150%);
  }
}

body {
  font-family: var(--default-font-family);
  font-size: 18px;

  background-color: var(--base-color);
  color: var(--base-color-text);

  margin: 0px;
  width: 100vw;
  max-width: 100vw;
  overflow-x: hidden;
}

h1,
h2,
h3,
h4,
nav a {
  font-family: var(--header-font-family);
  font-weight: 800;
  color: var(--base-color-text-title);
  margin-top: 0px;
}

h1 {
  font-size: 42px;
}

h2 {
  font-size: 36px;
}

h3 {
  font-size: 28px;
}

h4 {
  font-size: 22px;
}

hr {
  border: none;
  border-top: 2px solid var(--base-color-text);
}

.headline:after {
  content: " ";
  display: block;
  border: 1px solid var(--base-color-text-title);
  margin-bottom: 24px;
}

.container {
  width: 1200px;
  max-width: 1200px;
  margin: auto;
  overflow: visible;
}

.container-text {
  width: 100%;
  box-sizing: border-box;
  padding: 0 24px;
  max-width: 800px;
  margin: auto;
  overflow: visible;
}

.container-text h2 {
  margin-top: 20px;
  margin-bottom: 10px;
}

.container-text h3 {
  margin-top: 20px;
  margin-bottom: 10px;
}

.container-text h4 {
  margin-top: 10px;
  margin-bottom: 0px;
}

.flex {
  display: flex;
}

.flex.align-center {
  align-items: center;
}

header {
  width: 100vw;
  height: 60px;
  background-color: var(--navbar-background-color);
  display: flex;
  align-items: center;
  margin: 0 auto;
  box-shadow: var(--base-shadow);
}

header > div.container {
  width: 100%;
}

header .container {
  overflow: initial;
}

footer {
  background-color: var(--footer-background-color);
  color: var(--footer-color);
  font-size: 0.9em;
  margin-top: 60px;
}

p,
ul,
ol {
  text-rendering: optimizeLegibility;
  line-height: 1.5;
}

@media (min-width: 1400px) {
  .container > :first-child {
    padding-left: 0px;
  }
  .container > :last-child:not(a.btn) {
    padding-right: 0px;
  }
}

@media (max-width: 1250px) {
  body {
    width: auto;
  }

  .container {
    width: auto;
    padding-left: 16px;
    padding-right: 16px;
  }
}

#nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

#logo {
  padding: 0.2rem 0.5rem;
  margin-top: 0rem;
  margin-right: 25px;
  margin-left: -0.5rem;
}

#toggle-nav,
#toggle-nav-btn {
  display: none;
  line-height: 0px;
  cursor: pointer;
  user-select: none;
}

nav {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-right: 1rem;
}

nav a {
  text-decoration: none;
  font-size: 16px;
  font-weight: 600;
  color: var(--navbar-link-color);
  padding: 1.2rem 1rem 1.2rem;
}

nav a:hover,
#logo:hover {
  background-color: hsla(0, 0%, 50%, 10%);
}

nav ul {
  list-style: none;
  display: flex;
  align-items: center;
  height: 100%;
  margin: 0;
  padding-left: 0;
}

nav ul > :first-child {
  padding-left: 0;
}

nav ul > :last-child {
  padding-right: 0;
}

nav ul li {
  padding-left: 1rem;
  padding-right: 1rem;
  margin-bottom: 0.2rem;
  margin-left: -1rem;
  margin-right: -1rem;
}

nav li.active > a {
  color: var(--navbar-link-active-color);
}

.external-link:after {
  content: "";
  width: 18px;
  height: 18px;
  margin-left: 4px;
  background-image: url("/assets/icons/external-link.svg");
  background-position: center;
  background-repeat: no-repeat;
  background-size: contain;
  display: inline-block;
}

@media (prefers-color-scheme: dark) {
  nav a[href^="http"]:after {
    filter: invert(100%);
  }
}

@media (max-width: 800px) {
  header {
    height: auto;
  }

  header > div {
    flex-direction: column;
  }

  #nav-container {
    width: 100%;
  }

  #toggle-nav-btn {
    display: block;
    padding: 1.2rem;
    margin-top: -0.2rem;
    margin-right: -1rem;
  }

  #toggle-nav-btn:hover {
    background-color: hsla(0, 0%, 50%, 15%);
  }

  #toggle-nav-btn:active {
    background-color: hsla(0, 0%, 50%, 25%);
  }

  #toggle-nav:checked ~ header nav {
    display: block;
  }

  #nav {
    display: none;
  }

  nav ul {
    align-items: flex-start;
    flex-direction: column;
    height: auto;
  }

  nav > ul {
    margin-bottom: 15px;
  }

  nav ul li {
    padding: 15px 0 0 0;
    width: 100%;
  }

  nav ul a {
    width: 100%;
    display: block;
    padding: 0.75rem 1.5rem 0.75rem 1.5rem;
    margin-top: -0.5rem;
    margin-bottom: -0.5rem;
  }
}

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

footer {
  text-align: center;
}

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

.btn {
  background-color: var(--button-background-color);
  box-shadow: var(--base-shadow);
  font-size: 16px;
  display: inline-block;
  text-decoration: none;
  font-weight: bold;
}

.btn.btn-download {
  background-color: var(--navbar-background-color);
  text-align: center;
}

.btn.btn-download > .download-title {
  color: var(--base-color-text-title);
  display: inline-block;
  padding: 16px 32px;
}

.btn.btn-download > .download-hint {
  background-color: var(--primary-color);
  color: var(--primary-color-text);
  display: inline-block;
  padding: 16px;
  min-width: 46px;
}

.image-grid {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 10px;
}

.image-grid li {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding-bottom: 20px;
}

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

.caption {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  color: var(--base-color-text);
  text-align: center;
}