/* Minimal, clean academic style */

:root {
  --font-body: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, monospace;
  /* Dark mode (default) */
  --color-bg: #1a1a1a;
  --color-text: #e8e8e8;
  --color-muted: #999;
  --color-accent: #4a90ff;
  --color-accent-hover: #6aadff;
  --color-line: #333;
  --max-width: 780px;
  --space: 1.25rem;
  --space-sm: 0.6rem;
  --space-lg: 2.2rem;
  --line-height: 1.55;
}

/* Light mode */
[data-theme="light"] {
  --color-bg: #ffffff;
  --color-text: #1a1a1a;
  --color-muted: #555;
  --color-accent: #0046b8;
  --color-accent-hover: #003380;
  --color-line: #ccc;
}

* {
  box-sizing: border-box;
}

html {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: var(--line-height);
  -webkit-font-smoothing: antialiased;
}

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--color-accent);
  text-decoration: none;
}
a:hover,
a:focus {
  text-decoration: underline;
  color: var(--color-accent-hover);
}

.inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space);
}

.site-header {
  padding-top: var(--space-sm);
}

.header-bar {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space);
  flex-wrap: wrap;
  padding-bottom: var(--space-sm);
}

.site-name {
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: 0.5px;
}

.site-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: var(--space);
}
.site-nav a {
  font-size: 0.95rem;
  padding: 0.1rem 0;
  position: relative;
}
.site-nav a[aria-current="page"] {
  font-weight: 600;
}

.rule-under-header,
.rule-above-footer {
  border: 0;
  border-top: 1px solid var(--color-line);
  margin: 0;
}

.content {
  padding-top: var(--space-lg);
  padding-bottom: var(--space-lg);
  flex: 1;
}

.block + .block {
  margin-top: var(--space-lg);
}

h1, h2, h3 {
  line-height: 1.25;
  font-weight: 600;
  margin: 0 0 0.6rem;
}

h1 {
  font-size: 1.9rem;
}

h2 {
  font-size: 1.35rem;
  margin-top: 0;
}

h3 {
  font-size: 1.05rem;
  margin-top: 1.2rem;
}

p {
  margin: 0 0 1rem;
}

ul.simple-list {
  margin: 0.5rem 0 1.2rem;
  padding-left: 1.15rem;
}
ul.simple-list li {
  margin: 0.25rem 0;
}

/* Paper items with abstracts */
.copyright-notice {
  font-size: 0.85rem;
  color: var(--color-muted);
  font-style: italic;
  margin-bottom: 1.2rem;
  padding: 0.8rem;
  background: rgba(128, 128, 128, 0.08);
  border-radius: 4px;
}

.paper-list {
  list-style: disc;
  margin: 0.5rem 0 1.2rem;
  padding-left: 1.5rem;
}

.paper {
  margin-bottom: 1.8rem;
}

.paper-title {
  font-weight: 500;
  margin-bottom: 0.5rem;
  line-height: 1.4;
}

.paper-actions {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

.pdf-button {
  background: var(--color-accent);
  color: var(--color-bg);
  padding: 0.3rem 0.7rem;
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: 500;
  text-decoration: none;
  transition: background-color 0.2s;
  display: inline-block;
}

.pdf-button:hover {
  background: var(--color-accent-hover);
  text-decoration: none;
}

.coauthor {
  font-weight: 400;
  color: var(--color-muted);
}

.abstract-toggle {
  background: none;
  border: 1px solid var(--color-accent);
  color: var(--color-accent);
  padding: 0.3rem 0.7rem;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.8rem;
  margin-top: 0.3rem;
  transition: background-color 0.2s, color 0.2s;
}

.abstract-toggle:hover {
  background: var(--color-accent);
  color: var(--color-bg);
}

.abstract {
  display: none;
  margin-top: 0.8rem;
  padding: 1rem;
  background: rgba(128, 128, 128, 0.1);
  border-left: 3px solid var(--color-accent);
  border-radius: 4px;
}

.abstract.show {
  display: block;
}

.abstract p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.6;
}

.teaching-list .course {
  margin-bottom: 1.6rem;
}
.course h2 {
  font-size: 1.05rem;
  margin-bottom: 0.2rem;
}
.course .meta {
  font-size: 0.8rem;
  color: var(--color-muted);
  margin: 0 0 0.4rem;
}
.course .desc {
  margin: 0;
}

.site-footer {
  margin-top: var(--space-lg);
  padding-bottom: var(--space-lg);
}

.footer-content {
  padding-top: var(--space-sm);
  text-align: left;
}

.footer-content p {
  margin: 0 0 0.4rem;
}

.tiny {
  font-size: 0.75rem;
  color: var(--color-muted);
  margin-top: 0.8rem;
}

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0);
  white-space: nowrap; border: 0;
}

/* Profile sidebar - fixed to left margin */
/* Profile picture - always on top, centered */
.profile-sidebar {
  padding: var(--space) 0;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  gap: 2rem;
  flex-wrap: wrap;
}

.profile-picture {
  width: 280px;
  max-width: 90%;
  height: auto;
  border-radius: 8px;
  flex-shrink: 0;
}

/* Sidebar quote - very subtle, to the right of picture */
.sidebar-quote {
  padding: 1rem 1.5rem;
  max-width: 320px;
  text-align: left;
  opacity: 0.55;
  font-size: 0.7rem;
  line-height: 1.4;
  color: var(--color-muted);
  flex: 0 1 auto;
}

.sidebar-quote p {
  margin: 0 0 0.5rem;
}

.sidebar-quote .quote-attribution {
  margin-top: 0.8rem;
  font-size: 0.65rem;
  font-style: italic;
}

@media (max-width: 620px) {
  html { font-size: 16px; }
  .header-bar { flex-direction: column; align-items: flex-start; }
  .site-nav ul { gap: 1rem; }
  
  .profile-picture {
    width: 220px;
  }
}

/* Theme toggle button */
.theme-toggle {
  background: none;
  border: 1px solid var(--color-line);
  color: var(--color-text);
  padding: 0.4rem 0.8rem;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.85rem;
  transition: background-color 0.2s, border-color 0.2s;
}

.theme-toggle:hover {
  background: var(--color-line);
}