:root {
  --font-sans: "Metric", Helvetica, Arial, sans-serif;
  --font-mono: "Inconsolata", Monaco, Menlo, Consolas, "Courier New", monospace;

  --ink: #000000;
  --muted: #999999;
  --surface: #ffffff;
  --border: #e5e5e5;
  --navbar-bg: #f8f9fa;

  --accent: #00aa44;
  --accent-dark: #007722;
  --accent-soft: #a0ff7c;
  --on-accent: #ffffff;

  --focus-ring: 2px solid var(--accent);
  --transition-fast: 0.15s ease-in-out;
}

html {
  scroll-behavior: smooth;
}
html, body {
  height: 100%;
}
#wrap {
  min-height: 100%;
}
@font-face {
    font-family: 'Metric';
    src: url('../fonts/MetricWeb-Light.eot');
    src: url('../fonts/MetricWeb-Light.eot?#iefix') format('embedded-opentype'),
         url('../fonts/MetricWeb-Light.woff2') format('woff2'),
         url('../fonts/MetricWeb-Light.woff') format('woff');
    font-weight: normal;
    font-style: normal;
}
@font-face {
    font-family: 'Metric';
    src: url('../fonts/MetricWeb-LightItalic.eot');
    src: url('../fonts/MetricWeb-LightItalic.eot?#iefix') format('embedded-opentype'),
         url('../fonts/MetricWeb-LightItalic.woff2') format('woff2'),
         url('../fonts/MetricWeb-LightItalic.woff') format('woff');
    font-style: italic;
}
@font-face {
    font-family: 'Metric';
    src: url('../fonts/MetricWeb-Regular.eot');
    src: url('../fonts/MetricWeb-Regular.eot?#iefix') format('embedded-opentype'),
    		 url('../fonts/MetricWeb-Regular.woff2') format('woff2'),
         url('../fonts/MetricWeb-Regular.woff') format('woff');
    font-weight: bold;
}
body {
  font-family: var(--font-sans);
  font-size: 20px;
  color: var(--ink);
  background-color: var(--surface);
}
#main {
  padding-top: 1.5rem;
  padding-bottom: 2rem;
}
a {
  color: var(--accent);
  transition: color var(--transition-fast);
}
a:hover,
a:focus {
  color: var(--accent-dark);
  text-decoration: none;
}
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-sans);
  font-weight: bold;
}
@font-face {
    font-family: 'Inconsolata';
    src: url('../fonts/inconsolata-webfont.eot');
    src: url('../fonts/inconsolata-webfont.eot?#iefix') format('embedded-opentype'),
         url('../fonts/inconsolata-webfont.woff') format('woff'),
         url('../fonts/inconsolata-webfont.ttf') format('truetype'),
         url('../fonts/inconsolata-webfont.svg#inconsolatamedium') format('svg');
    font-weight: normal;
    font-style: normal;
}

code,
pre {
  font-family: var(--font-mono);
}
.bibtex {
	font-size: 10px;
}

.img-thumbnail {
  transition: border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}
.img-thumbnail:hover,
.img-thumbnail:focus {
  border-color: var(--accent-dark);
  transform: translateY(-4px);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.12);
}
[data-bs-theme="dark"] .img-thumbnail:hover,
[data-bs-theme="dark"] .img-thumbnail:focus {
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.5);
}

.hero-img {
  overflow: hidden;
}
.hero-img img {
  display: block;
}

.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background-color: var(--accent);
  transform: scaleX(0);
  transform-origin: 0 50%;
  z-index: 1040;
  pointer-events: none;
}

.back-to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  width: 3rem;
  height: 3rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  border: none;
  background-color: var(--accent);
  color: var(--on-accent);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  opacity: 0;
  visibility: hidden;
  transform: translateY(0.5rem);
  transition: opacity var(--transition-fast), visibility var(--transition-fast),
              transform var(--transition-fast), background-color var(--transition-fast);
  z-index: 1035;
}
.back-to-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.back-to-top:hover,
.back-to-top:focus {
  background-color: var(--accent-dark);
  color: var(--on-accent);
}

.navbar-brand {
  font-size: 20px;
  color: var(--ink) !important;
  font-weight: bold;
}

.navbar {
  position: sticky;
  top: 0;
  z-index: 1030;
  background-color: rgba(248, 249, 250, 0.82);
  -webkit-backdrop-filter: blur(12px) saturate(160%);
  backdrop-filter: blur(12px) saturate(160%);
  box-shadow: 0 1px 0 var(--border);
  transition: box-shadow var(--transition-fast), background-color var(--transition-fast);
}
.navbar.navbar-scrolled {
  box-shadow: 0 1px 0 var(--border), 0 8px 24px rgba(0, 0, 0, 0.12);
}
.navbar .navbar-nav .nav-link {
  color: var(--ink);
  position: relative;
}
.navbar .navbar-nav .nav-link:hover,
.navbar .navbar-nav .nav-link:focus {
  color: var(--accent);
}
.navbar .navbar-nav .nav-link.active {
  color: var(--accent);
}
.navbar .navbar-nav .nav-link:not(.dropdown-toggle):not(button)::after {
  content: "";
  position: absolute;
  left: 0.5rem;
  right: 0.5rem;
  bottom: 0.25rem;
  height: 2px;
  border-radius: 1px;
  background-color: var(--accent);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.25s ease;
}
.navbar .navbar-nav .nav-link:not(.dropdown-toggle):not(button):hover::after,
.navbar .navbar-nav .nav-link:not(.dropdown-toggle):not(button).active::after {
  transform: scaleX(1);
}

/* links */
.papers-sidebar .nav>li>a {
  color: var(--ink);
  font-size: 16px;
}
/* nested links */
.papers-sidebar .nav .nav>li>a {
  color: var(--muted);
  font-size: 12px;
}
/* active links */
.nav-pills .nav-link.active {
  color: var(--on-accent);
  background-color: var(--accent);
}
/* active nested links */
.nav-pills .nav-pills .nav-link.active {
  color: var(--on-accent);
  background-color: var(--accent);
}
/* hover links */
.papers-sidebar .nav>li>a:hover,
.papers-sidebar .nav>li>a:focus {
  color: var(--on-accent);
  background-color: var(--accent-dark);
}

.nav-link {
  transition: color var(--transition-fast);
}

.dropdown-item {
  transition: color var(--transition-fast), background-color var(--transition-fast);
}
.dropdown-item:hover,
.dropdown-item:focus {
  color: var(--on-accent);
  background-color: var(--accent-dark);
}
.dropdown-item.active,
.dropdown-item:active {
  color: var(--on-accent);
  background-color: var(--accent);
}

.tud-logo {
  max-height: 35px;
  margin-top: -5px;
  transition: opacity var(--transition-fast);
}
.tud-logo:hover {
  opacity: 0.85;
}

.grey {
  color: var(--muted);
}

.text-input {
  display: block;
  width: 100%;
  padding: 0.375rem 0.75rem;
  margin-bottom: 0.5rem;
  font-size: 1rem;
  color: var(--ink);
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: 0.375rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}
.text-input:focus {
  border-color: var(--accent);
  outline: 0;
  box-shadow: 0 0 0 0.2rem rgba(0, 170, 68, 0.25);
}

.blog-list {
  list-style: none;
  padding: 0;
  margin-bottom: 1rem;
}
.blog-list li {
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border);
}
.blog-list li:last-child {
  border-bottom: none;
}
.blog-list .blog-date {
  display: inline-block;
  min-width: 9.5rem;
  color: var(--muted);
}

.theme-dark-only {
  display: none;
}

mark {
  background: var(--accent-soft);
  padding: 0em;
}
::selection {
  background: var(--accent-soft);
}

/* draw-on-hover underline for in-content links */
#main a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i)),
.footer a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i)) {
  position: relative;
  text-decoration: none;
}
#main a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i))::after,
.footer a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i))::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -0.08em;
  height: 1px;
  background-color: currentColor;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.25s ease;
}
#main a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i)):hover::after,
#main a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i)):focus-visible::after,
.footer a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i)):hover::after,
.footer a:not(.nav-link):not(.dropdown-item):not(.navbar-brand):not(:has(img, i)):focus-visible::after {
  transform: scaleX(1);
}

/* theme-toggle spin */
@keyframes theme-toggle-spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}
#theme-toggle.spin {
  animation: theme-toggle-spin 0.4s ease;
}
@media (prefers-reduced-motion: reduce) {
  #theme-toggle.spin {
    animation: none;
  }
}

a:focus-visible,
button:focus-visible,
.dropdown-item:focus-visible,
.nav-link:focus-visible {
  outline: var(--focus-ring);
  outline-offset: 2px;
}

[data-bs-theme="dark"] {
  --ink: #dee2e6;
  --muted: #868e96;
  --surface: #212529;
  --border: #343a40;
  --navbar-bg: #1a1d20;
  --accent: #37c76c;
  --accent-dark: #2ba355;
  --accent-soft: #1f5130;
}

[data-bs-theme="dark"] .navbar {
  background-color: rgba(26, 29, 32, 0.82);
}
[data-bs-theme="dark"] .navbar.navbar-scrolled {
  box-shadow: 0 1px 0 var(--border), 0 8px 24px rgba(0, 0, 0, 0.5);
}

[data-bs-theme="dark"] .theme-dark-only {
  display: inline-block;
}
[data-bs-theme="dark"] .theme-light-only {
  display: none;
}

[data-bs-theme="dark"] .highlight {
  background-color: #1a1d20;
}
[data-bs-theme="dark"] pre {
  color: #dee2e6;
}