:root {
  --margin: 1rem;
  --padding: 1rem;
  --border-radius: .3rem;
  --header-height: 8rem;
  --nav-height: 2.5rem;
  --nav-z-index: 2000;
  --gray: rgb(60, 60, 60);
  --blue: rgb(20, 120, 223);
  --yellow: rgb(255, 150, 0);
  --red: rgb(200, 30, 10);
  --green: rgb(30, 160, 10);
  --accent-color: rgb(100, 0, 200);

  --very-light-blue: rgb(250, 250, 255);
  --light-blue: rgb(225, 225, 240);
  --medium-blue: rgb(160, 160, 255);
  --accent-blue: rgb(105, 105, 200);
  --dark-blue: rgb(0, 0, 65);
}

html.dark {
  --invert: 1;
  --text-color: rgb(215, 215, 215);
  --quote-color: rgb(145, 145, 145);
  --box-shadow: -0.5rem .5rem 1rem rgba(255, 255, 255, 0.2);
  --section-border-top: 1px solid rgba(255, 255, 255, 0.4);
  --nav-background-color: rgba(0, 0, 20, 0.9);
  --section-background-color: rgb(0, 0, 25);
  --band-background-color: rgba(0, 0, 0, 0.4);
  --card-background-color: rgba(40, 40, 40, 0.4);
  --footer-background-color: rgba(80, 80, 100, 0.8);
  --background: linear-gradient(to right, rgb(175, 0, 75), rgb(100, 0, 200));
  --article-background: linear-gradient(to right, rgb(60, 60, 80), var(--section-background-color));
}

html.light {
  --invert: 0;
  --text-color: var(--dark-blue);
  --quote-color: rgb(60, 60, 90);
  --box-shadow: -0.25rem 0.25rem .5rem rgba(105, 105, 200, 0.9);
  --section-border-top: 1px solid rgba(0, 0, 95, 0.5);
  --nav-background-color: var(--very-light-blue);
  --section-background-color: var(--light-blue);
  --band-background-color: rgba(200, 200, 250, 0.8);
  --card-background-color: rgba(140, 140, 140, 0.4);
  --footer-background-color: rgb(200, 200, 250);
  --article-background: linear-gradient(to right, var(--medium-blue), var(--very-light-blue));
  --background: linear-gradient(to right, var(--accent-blue), var(--very-light-blue));
}

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

html {
  font-size: 200%;
}

h1 {
  font-size: 2.2em;
}

h2 {
  font-size: 1.5em;
  margin-bottom: calc(var(--margin) / 2);
}

h3 {
  font-size: 1.1em; 
  margin-top: var(--margin);
}

ol {
  margin-left: 1.5rem;
  font-size: .9em;
}

ul {
  list-style-type: none;
  padding: 0;
}

a {
  text-decoration: none;
  font-weight: bold;
}

.btn {  
  color: white;
  display: inline-block;
  background-color: rgb(60, 60, 60);
  font-size: 1.2em;
  line-height: 1;
  vertical-align: middle;
  white-space: nowrap;
  padding: 0.5rem 1rem;
  border-radius: var(--border-radius);
  text-decoration: none;
  font-weight: bold;
  transition: all 0.3s ease;
}

.btn:hover {
  background-color: rgb(80, 80, 80);
}
.btn:active {
  background-color: var(--accent-color);
}

.btn:hover {
  background-color: rgb(80, 80, 80);
}
.btn:active {
  background-color: var(--accent-color);
}

.invert {
  filter: invert(var(--invert));
}

body {
  font-size: 1rem;
  background: var(--background);
  color: var(--text-color);
  font-family: Arial;
}

header {
  display: flex;
  background-color: var(--nav-background-color);
  padding: 1rem;
  height: var(--header-height);
  width: 100%;
}

nav {
  background-color: var(--nav-background-color);
  position: sticky;
  top: 0;
  height: var(--nav-height);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  line-height: var(--nav-height);
  z-index: var(--nav-z-index);
}

nav ul {
  display: flex;
  flex-direction: row;
  padding: 0;
}

nav ul li {
  flex: 1;
  text-align: center;
}
nav ul li a {
  color: var(--text-color);
  text-decoration: none;
  font-size: 1.2em;
  font-weight: bold;
}

nav ul li a:hover {
  text-decoration: underline;
}

main {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 5rem;
  padding-bottom: 8rem;
}

main > section {
  background-color: var(--section-background-color);
  opacity: 0;
  min-height: 20rem;
  width: 80vw;
  padding: var(--padding);
  margin: 10rem 0;
  border-radius: var(--border-radius);
  box-shadow: 0 0 0 rgba(0, 0, 0, 0);
  transition: all .5s ease;
}

main > section.view {
  opacity: 1;
  margin: var(--margin) 0;
  border-top: var(--section-border-top);
  box-shadow: var(--box-shadow);
}

article {
  background: var(--article-background);
}

article section {
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 5rem;
  padding: 3rem 3rem;
  width: 100vw;
}

div.band {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  background-color: var(--band-background-color);
  padding: 3rem 3rem;
  width: 100vw;
}

div.card {
  background-color: var(--card-background-color);
  max-width: 40rem;
  padding: var(--padding);
  border-radius: calc(var(--border-radius) + var(--padding));
}

div.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(18rem, 1fr));
  gap: var(--margin);
}

.text-content {
  justify-content: center;
  max-width: 50;
  padding: var(--padding);
}

.text-content p {
  line-height: 1.5;
  max-width: 35rem;
  padding: var(--padding);
}

.postscript {
  color: rgb(145, 145, 145);
  font-style: italic;
  font-size: 0.8em;
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: var(--margin);
  padding: var(--padding);
  max-width: 40rem;
}

.quote {
  color: var(--quote-color);
  font-style: italic;
  font-size: 1.2em;
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: var(--margin);
  padding: var(--padding);
  max-width: 40rem;
}

footer {
  bottom: 0;
  left: 0;
  background-color: var(--footer-background-color);
  text-align: center;
  width: 100%;
  padding: 2.5rem;
}

@media (max-width: 2800px) {
  html {
    font-size: 100%;
  }
}

@media (max-width: 950px) {
  html {
    font-size: 85%;
  }
  main > section {
    width: 90vw;
  }
}

@media (max-width: 550px) {
  html {
    font-size: 75%;
  }
  main > section {
    width: 100vw;
  }
}