/* CSS is how you can add style to your website, such as colors, fonts, and positioning of your
/* cyanobacteria.css */

/* --- Light mode defaults --- */
:root {
  --text: darkslategrey;
  --border: lightgrey;
  --accent: teal;
  --bg: #dce3e1;
  --gradientTop: white;
  --gradientBottom: rgba(240, 248, 255, 0.8);
}

header {
  /* Replace with your own image if you want */
  background: url("banner-light.jpg"), teal;
  background-size: cover;
  background-position: center;
}

/* --- Dark mode overrides --- */
@media (prefers-color-scheme: dark) {
  :root {
    --text: white;
    --border: #5a7678;
    --accent: #74C365;
    --bg: rgba(0, 60, 60, 0.8);
    --gradientBottom: rgb(0, 50, 60);
    --gradientTop: darkslategrey;
  }

  a:link {
    color: lightblue;
  }

  header {
    background: url("banner-dark.jpg"), darkslategrey;
    background-size: cover;
    background-position: center;
  }
}

/* --- Global resets --- */
* {
  box-sizing: border-box;
}

body {
  padding: 10px;
  font-family: 'MS PGothic', sans-serif;
  color: var(--text);

  /* background pattern */
  background-color: var(--gradientTop);
  background-image:
    linear-gradient(30deg, var(--bg) 12%, transparent 12.5%, transparent 87%, var(--bg) 87.5%, var(--bg)),
    linear-gradient(150deg, var(--bg) 12%, transparent 12.5%, transparent 87%, var(--bg) 87.5%, var(--bg)),
    linear-gradient(30deg, var(--bg) 12%, transparent 12.5%, transparent 87%, var(--bg) 87.5%, var(--bg)),
    linear-gradient(150deg, var(--bg) 12%, transparent 12.5%, transparent 87%, var(--bg) 87.5%, var(--bg)),
    linear-gradient(60deg, var(--bg) 25%, transparent 25.5%, transparent 75%, var(--bg) 75%, var(--bg)),
    linear-gradient(60deg, var(--bg) 25%, transparent 25.5%, transparent 75%, var(--bg) 75%, var(--bg));
  background-size: 20px 35px;
  background-position: 0 0, 0 0, 10px 18px, 10px 18px, 0 0, 10px 18px;
}

/* --- Container and layout --- */
.container {
  max-width: 55rem;
  margin: 5vw auto 12px auto;
  border: 6px ridge var(--border);
  outline: 3px solid var(--gradientTop);
  outline-offset: 4px;
  border-radius: 10px;
  display: flex;
  flex-wrap: wrap;
  padding: 5px;
  gap: 5px;

  background-color: var(--gradientBottom);
  background-image:
    repeating-radial-gradient(circle at 0 0, transparent 0, var(--gradientBottom) 9px),
    repeating-linear-gradient(var(--bg), var(--bg));
}

/* column widths */
.small { flex: 1 1 9%; }
.large { flex: 1 1 82%; }
.full  { flex: 1 1 100%; }
.half  { flex: 1 1 49%; }

/* --- Header --- */
header {
  width: 100%;
  height: 120px;
  border: 2px ridge var(--border);
  border-radius: 5px;
  position: relative;
}

header span {
  font-size: 2.5rem;
  position: absolute;
  bottom: 0;
  right: 10px;
  margin: 10px;
  font-weight: bold;
  text-shadow: 
    1px 1px var(--text),
    -1px 1px var(--text),
    1px -1px var(--accent),
    -1px -1px var(--accent);
  color: var(--gradientTop);
}

/* --- Navigation --- */
nav {
  border: 2px ridge var(--border);
  border-radius: 5px;
  padding: 5px;
  background: linear-gradient(var(--gradientTop), var(--gradientBottom));
}

nav div {
  text-align: center;
  font-size: 1.25rem;
  margin: 5px 5px 10px 5px;
}

nav a {
  display: block;
  margin: 5px;
  background: linear-gradient(to right, var(--bg), var(--gradientBottom));
  border-radius: 5px;
  padding: 2px 7px;
  text-decoration: none;
}

nav a:link,
nav a:visited {
  color: var(--text);
}

nav a:hover,
nav a:focus {
  background: linear-gradient(to right, var(--bg), var(--gradientBottom), var(--gradientTop));
}

/* optional button styling */
div.small > img {
  display: block;
  margin: 5px auto;
  border: 2px ridge var(--border);
  border-radius: 5px;
}

/* --- Sections --- */
section {
  border: 2px ridge var(--border);
  border-radius: 5px;
  background: linear-gradient(var(--gradientTop), var(--gradientBottom));
  padding: 5px;
}

/* --- Footer --- */
footer {
  text-align: center;
  margin-bottom: 5vw;
  font-size: 0.8rem;
}

footer a {
  text-decoration: none;
}

/* --- Text styling --- */
h1, h2, h3, h4, h5, h6, p {
  margin: 5px;
  line-height: 1.2;
}

h1 {
  font-size: 1.4rem;
  letter-spacing: 2px;
  font-weight: normal;
  text-align: center;
  border-bottom: 2px ridge var(--border);
  padding-bottom: 5px;
}

h2 {
  font-size: 1.25rem;
  font-weight: normal;
  text-align: center;
}

h3 {
  font-size: 1.1rem;
}

h4 {
  font-size: 1rem;
  color: var(--accent);
  padding-left: 12px;
}

/* --- Media/content safety --- */
img { max-width: 100%; }
pre { overflow-x: auto; }

/* --- Links --- */
a:hover, a:focus {
  font-style: italic;
}

a:visited {
  color: var(--accent);
}