:root {
  --tu-green: #639A00;
  --hover-dark:#616161;
  --light-gray: #F4F4F4;
  --dark-red: #cc0000;
}

/* Grundlegende Typografie */
body {
  font-family: Arial, Helvetica, sans-serif;
  font-size: 16px;
  line-height: 1.4;
  margin: 2em;
  color: #222;
  background: var(--light-gray);
}

/* Überschriften */
h1, h2, h3, h4, h5, h6 {
  color: var(--tu-green);
  font-weight: bold;
}

/* Links */
a {
  color: var(--tu-green);
  text-decoration: none;
}
a:not([href]) {
  cursor: default;
}
a[href] {
  text-decoration: underline;
}
a[href]:hover {
  background-color: var(--hover-dark);
  color: white;
  text-decoration: none;
}

/* Farben für Inline <font> */
font[color="blue"],
font[color="green"],
font[color="#3399FF"],
font[color="#00FF00"] {
  color: var(--tu-green);
}
font[color="red"],
font[color="#FF0000"] {
  color: var(--dark-red);
}

/* Header / Navigation */
.site-header {
  background: var(--tu-green);
  padding: 0 0;
  margin-bottom: 0;
  border-bottom: 1px solid #6f8f36;
}

.site-header nav {
  display: flex;
  align-items: stretch;
}

.site-header nav a {
  display: flex;
  align-items: center;
  padding: 0.5em 1em;
  text-decoration: none;
  color: #fff;
  font-weight: bold;
}

.site-header nav a:hover {
  background-color: var(--hover-dark);
  color: white;
}

/* Klappbare Inhalte */
details {
  margin-bottom: 1em;
  border-left: 4px solid #639A00; /* TU-grün optional */
  padding-left: .7em;
  border-radius: 6px;
}
summary {
  font-size: 1.2em;
  font-weight: bold;
  cursor: pointer;
  list-style: none;
}

summary::after {
  content: none;
  font-weight: normal;
  color: var(--tu-green);
  font-size: 0.9em;
}

details[open] summary::after {
  content: none;
  color: var(--tu-green);
}

details:not([open]) summary:hover {
  transform: translate(.5em,0);
  transition: transform 0.1s ease;
}