/* Dark theme */
:root {
  --background-color: #2d2d2d;
  --headings-color: #ffffff;
  --font-color: #ffffff;
  --border-color: #ffffff;
  --line-color: #ffffff;
  --link-color: #CC99FF;
  --link-color-hover: #ffffff;
}

/* Light theme */
html[data-theme='light'] {
  --background-color: #ffffff;
  --headings-color: #181818;
  --font-color: #181818;
  --line-color: #181818;
  --nav-link-color: #2599fd;
  --nav-link-color-hover: #000000;
  --link-color: #CC99FF;
  --link-color-hover: #000000;
}

body {
  background-color: var(--background-color);
  color: var(--font-color);
  font-family: 'Open Sans', sans-serif;
  font-display: swap;
  font-size: 1rem;
  line-height: 1.6;
}

h1, h2, h3, h4, h5 {
  color: var(--headings-color);
  font-weight: bold;
}

hr {
  background-color: var(--line-color);
}

header {
  background-color: var(--background-color);
}

nav {
  align-items: center;
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  max-width: 1200px;
  margin: 0 auto;
}

nav li {
  font-size: 1rem;
  padding: 2px 8px;
  text-align: center;
}

nav li a {
  text-decoration: none;
}

li a:hover {
  border-bottom: 2px solid var(--line-color);
  text-decoration: none;
}

a {
  color: var(--link-color);
}

a:hover {
  color: var(--link-color-hover);
}

/* Banner */
.overlay {
  background-size: cover;
  background-position: center;
  border-bottom: 2px solid var(--border-color);
  border-top: 2px solid var(--border-color);
  display: flex;
  min-height: 200px;
  text-align: center;
  align-items: center;
  justify-content: center;
}

.title {
  display: inline-block;
  font-size: 3rem;
  text-decoration: none;
}

/* Content */
main {
  margin-top: 20px;
}

section {
  border-radius: 5px;
  padding: 5px 20px;
}

/* Simple css to style it like a toggle switch */
.theme-switch-wrapper {
  display: flex;
  align-items: center;
}

.theme-switch {
  display: inline-block;
  height: 24px;
  position: relative;
  width: 40px;
}

.theme-switch input {
  display: none;
}

.slider {
  background-color: #ccc;
  bottom: 0;
  cursor: pointer;
  left: 0;
  position: absolute;
  right: 0;
  top: 0;
  transition: .2s;
}

.slider:before {
  background-color: #fff;
  bottom: 4px;
  content: "";
  height: 16px;
  left: 4px;
  position: absolute;
  transition: .2s;
  width: 16px;
}

input:checked + .slider {
  background-color: #66bb6a;
}

input:checked + .slider:before {
  transform: translateX(16px);
}

.slider.round {
  border-radius: 34px;
}

.slider.round:before {
  border-radius: 50%;
}

footer {
  border-top: 3px solid var(--border-color);
  margin-top: 30px;
}

/* Responsive layout - when the screen is less than 700px wide, make the two columns stack on top of each other instead of next to each other */
@media screen and (max-width: 700px) {
  .title {
    display: block;
    text-align: center;
  }

  nav {
    flex-direction: column;
  }

  nav ul {
    flex-direction: column;
    margin: 0 auto;
  }

  nav ul li a {
    text-align: center;
    margin: 0 auto;
  }
}