:root {
    --primary-dark: rgb(24, 61, 115);
    --primary: rgb(34, 83, 154);
    --primary-hover: rgb(61, 117, 200);
    --primary-even-whiter: rgb(9, 108, 255);
    --secondary: #2c3e50;
    --accent: #e74c3c;
    --koat: #930f00;
    --loat: #005f7a;
    --light: #ffffff;
    --light-gray: #f8f9fa;
    --medium-gray: #e9ecef;
    --dark-gray: #6c757d;
    --dark: #343a40;
    --success: #2ecc71;
    --text: #131517;
    --text-light: #495055;
    --border: #dee2e6;
}

.bg-primary {
  background-color: var(--primary-even-whiter);
  margin: 0;
  padding-bottom: 0;
  padding-top: 0;
}

/* ===== Reset / Base ===== */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
    font-family: Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: #222;
    background-color: #ffffff;
    margin: 0;
    line-height: 1.6;
}

a {
  color: --primary;           /* RWTH-style blue/dark shade */
  text-decoration: none;
}

a:hover, a:focus {
  text-decoration: underline;
}

/* ===== Headings ===== */
h1, h2, h3, h4, h5 {
  color: --primary-dark;
  font-weight: normal;
  margin-bottom: 0.5em;
}

h1 {
  font-size: 2.4em;
  margin-top: 0.4em;
}
h2 {
  font-size: 1.9em;
  margin-top: 1.2em;
  border-bottom: 2px solid var(--medium-gray);
}
h3 {
  font-size: 1.5em;
  margin-top: 1em;
}

/* ===== Paragraphs & Text ===== */
p {
  margin-bottom: 1em;
}

ul, ol {
  margin: 0 0 1em 1.2em;
}

blockquote {
  margin: 1em 0;
  padding-left: 1em;
  border-left: 4px solid #ccc;
  color: #555;
  background-color: #f9f9f9;
}

/* ===== Layout / Wrapper / Sections ===== */
header, nav, main, footer, section {
  width: 100%;
}

header, nav {
  margin-bottom: 1.5em;
}

section {
  margin-bottom: 2em;
}

/* ===== Navigation (if present) ===== */
nav ul {
  list-style: none;
  padding-left: 0;
}

nav li {
  display: inline-block;
  margin-right: 1em;
}

/* ===== Images / Media ===== */
img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 1em 0;
}

/* ===== Modern Table Styling ===== */

table {
  width: 100%;
  border-collapse: separate;   /* allows custom rounding and spacing */
  border-spacing: 0 8px;       /* spacing between rows */
  margin-bottom: 2em;
  font-size: 0.95rem;
}

table th {
  background: #00549F;     /* RWTH blue */
  color: white;
  padding: 0.75em 1em;
  text-align: left;
  font-weight: 600;
  border: none;
}

table td {
  background: #f9f9f9;
  padding: 0.75em 1em;
  border: none;
  border-top: 1px solid #e0e0e0;
}

table tr:first-of-type td,
table tr:first-of-type th {
  border-top: none;
}

/* Rounded corners for the first and last cell of each row */
table tr td:first-child,
table tr th:first-child {
  border-radius: 6px 0 0 6px;
}

table tr td:last-child,
table tr th:last-child {
  border-radius: 0 6px 6px 0;
}

/* Vertical header cell (room number) */ 
.vertical {
  background: #eee;
  color: #333;
  font-weight: bold;
  text-align: center;
  border-radius: 6px !important;
  min-width: 40px;
}


/* Remaining column widths */
table th:nth-child(2) { width: 42.2%; }
table th:nth-child(3) { width: 10%; }
table th:nth-child(4) { width: 40%; }


/* ===== Code / Preformatted ===== */
code, pre {
  font-family: monospace;
  background-color: #f4f4f4;
  padding: 0.2em 0.4em;
  font-size: 0.95em;
}

pre {
  overflow-x: auto;
  padding: 1em;
  margin: 1em 0;
}

/* ===== Footer ===== */
footer {
  margin-top: 2em;
  padding-top: 1em;
  border-top: 1px solid #ccc;
  font-size: 0.9em;
  color: #555;
}

/* ===== Utility / Classes (optional) ===== */
/* Centered block, e.g. for notices or wrappers */
.center {
  text-align: center;
}

/* Small note / disclaimer style */
.note {
  font-size: 0.9em;
  color: #555;
}

/* Button-like link (if you want a download link or action link) */
.btn {
  display: inline-block;
  padding: 0.5em 1em;
  background-color: --primary-dark;
  color: #fff;
  text-decoration: none;
  border-radius: 4px;
  margin: 0.5em 0;
}

.btn:hover {
  background-color: #002244;
}

/* ===== Responsive tweaks ===== */
@media (max-width: 600px) {
  body {
    padding: 10px;
  }
  h1 {
    font-size: 2em;
  }
  h2 {
    font-size: 1.6em;
  }
}

/* Remaining column widths */
table th:nth-child(2) { width: 42.2%; }
table th:nth-child(3) { width: 10%; }
table th:nth-child(4) { width: 40%; }

/* Container for the blocks */
.blocks-container {
    display: flex;
    gap: 20px; /* space between blocks */
    flex-wrap: wrap; /* allows wrapping on smaller screens */
    justify-content: space-between;
    margin: 20px 0;
}

/* Each block */
.block {
    background-color: var(--light-gray); /* fallback color */
    background-size: cover;      /* make image cover entire block */
    background-position: center; /* center the image */
    background-repeat: no-repeat;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
    flex: 1 1 calc(33.333% - 20px);
    transition: transform 0.2s, box-shadow 0.2s;
    text-align: center;
    color: var(--text); /* ensure text is readable */
    display: flex;
    flex-direction: column;
}

/* Example: different images for each block */
.block:nth-child(1) {
    background: 
        linear-gradient(rgba(255, 255, 255, 0.85), rgba(255, 255, 255, 0.85)), 
        url('./pics/AProVE_P_Small.png');
    background-size: cover;      
    background-position: center; 
    background-repeat: no-repeat;
}

.block:nth-child(1) h2 {
    color: var(--primary);
    border-bottom: none;
}

.block:nth-child(2) {
    background: 
        linear-gradient(rgba(255, 255, 255, 0.85), rgba(255, 255, 255, 0.85)), 
        url('./pics/KoAT.png');
    background-size: cover;      
    background-position: center; 
    background-repeat: no-repeat;
}

.block:nth-child(2) h2 {
    color: var(--koat);
    border-bottom: none;
}

.block:nth-child(3) {
    background: 
        linear-gradient(rgba(255, 255, 255, 0.85), rgba(255, 255, 255, 0.85)), 
        url('./pics/LoAT.png');
    background-size: cover;      
    background-position: center; 
    background-repeat: no-repeat;
}

.block:nth-child(3) h2 {
    color: var(--loat);
    border-bottom: none;
}

/* Hover effect */
.block:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

/* Block headings */
.block h2 {
    color: var(--primary-dark);
    font-weight: bold;
}

/* Block paragraphs */
.block p {
    color: var(--text); /* ensure text is readable */
    margin-bottom: 15px;
}

/* Button inside block */
.btn {
    display: inline-block;
    padding: 8px 16px;
    background-color: var(--primary);
    color: var(--light);
    text-decoration: none;
    border-radius: 4px;
    transition: background-color 0.2s;
    margin-top: auto;
}

.btn:hover {
    background-color: var(--primary-hover);
}

/* Responsive: stack blocks on small screens */
@media (max-width: 900px) {
    .block {
        flex: 1 1 100%;
    }
}

/* ----------- Topbar ----------- */
.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--primary-even-whiter);
    padding: 0px 20px;
    color: white;
}

.topbar a {
    color: white;
    font-weight: 500;
}

/* ----------- Layout Container ----------- */
.container {
    max-width: 1100px;
    margin: auto;
    padding: 20px;
}

/* ----------- Footer ----------- */
.footer {
    text-align: center;
    background: #eee;
    padding: 20px;
    margin-top: 40px;
}

/* ----------- Responsive ----------- */
@media (max-width: 768px) {
    .projects {
        flex-direction: column;
    }
    
    .project-card {
        flex: 1 1 100%;
    }

    .topbar {
        flex-direction: column;
        text-align: center;
        gap: 10px;
    }
}

/* ===== Navigation Bar ===== */

.navbar {
  background: #00549F; /* RWTH blue */
  padding: 0.6em 0;
  position: sticky;
  top: 0;
  z-index: 1000; /* stays on top during scroll */
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

/* Container for alignment */
.nav-container {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 1em;
}

.nav-container a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  padding: 0.4em 0;
  transition: opacity 0.2s;
  font-weight: bold;
}

.nav-logo {
  color: white;
  font-weight: 600;
  text-decoration: none;
  font-size: 1.1em;
}

/* Navigation links */
.nav-links {
  list-style: none;
  display: flex;
  gap: 1.5em;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  padding: 0.4em 0;
  transition: opacity 0.2s;
}

.nav-links a:hover {
  opacity: 0.75;
}

/* ===== Responsive (mobile) ===== */
@media (max-width: 700px) {
  .nav-links {
    display: none; /* hide menu for now */
  }

  .navbar {
    text-align: center;
  }

  .nav-logo {
    margin: auto;
  }
}

/* Example CSS — tailor to your main site CSS */
#teaching {
  max-width: 800px;
  margin: 0 auto;
  padding: 40px 20px;
}

#teaching h2 {
  font-size: 2em;
  margin-bottom: 1em;
  border-bottom: 2px solid #ccc;
  padding-bottom: 0.3em;
}

.teaching-list {
  list-style: none;
  padding-left: 0;
}

.teaching-list li {
  margin-bottom: 1.8em;
}

.teaching-list h3 {
  font-size: 1.4em;
  margin: 0;
  color: #333;
}

.teaching-list p {
  margin: 0.4em 0;
  line-height: 1.5;
}

/* Section headings inside the teaching block */
#teaching_2 h2 {
    border-bottom: 2px solid var(--medium-gray);
    padding-bottom: 0.3em;
    margin-top: 1.5em;
}

/* Remove default list style */
#teaching_2 .teaching-list {
    list-style: none;
    padding-left: 0;
    margin-top: 1.2em;
}

/* Box-style teaching entry */
#teaching_2 .teaching-list li {
    background: white;
    border: 1px solid var(--border);
    padding: 18px 20px;
    border-radius: 12px;
    margin-bottom: 1.5em;
    box-shadow: 0 2px 4px rgba(0,0,0,0.06);
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

/* Titles */
#teaching_2 .teaching-list h3 {
    margin-bottom: 0.4em;
    font-size: 1.3em;
    color: var(--primary-dark);
}

/* Paragraphs */
#teaching_2 .teaching-list p {
    margin: 0.4em 0;
    color: var(--text-light);
}



.highlight-text {
  color: var(--primary);
}