/* latin-ext */
@font-face {
  font-family: 'Lato';
  font-style: italic;
  font-weight: 400;
  src: local('Lato Italic'), local('Lato-Italic'), url(https://fonts.gstatic.com/s/lato/v15/S6u8w4BMUTPHjxsAUi-qNiXg7eU0.woff2) format('woff2');
  unicode-range: U+0100-024F, U+0259, U+1E00-1EFF, U+2020, U+20A0-20AB, U+20AD-20CF, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Lato';
  font-style: italic;
  font-weight: 400;
  src: local('Lato Italic'), local('Lato-Italic'), url(https://fonts.gstatic.com/s/lato/v15/S6u8w4BMUTPHjxsAXC-qNiXg7Q.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
/* latin-ext */
@font-face {
  font-family: 'Lato';
  font-style: italic;
  font-weight: 700;
  src: local('Lato Bold Italic'), local('Lato-BoldItalic'), url(https://fonts.gstatic.com/s/lato/v15/S6u_w4BMUTPHjxsI5wq_FQftx9897sxZ.woff2) format('woff2');
  unicode-range: U+0100-024F, U+0259, U+1E00-1EFF, U+2020, U+20A0-20AB, U+20AD-20CF, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Lato';
  font-style: italic;
  font-weight: 700;
  src: local('Lato Bold Italic'), local('Lato-BoldItalic'), url(https://fonts.gstatic.com/s/lato/v15/S6u_w4BMUTPHjxsI5wq_Gwftx9897g.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
/* latin-ext */
@font-face {
  font-family: 'Lato';
  font-style: normal;
  font-weight: 400;
  src: local('Lato Regular'), local('Lato-Regular'), url(https://fonts.gstatic.com/s/lato/v15/S6uyw4BMUTPHjxAwXiWtFCfQ7A.woff2) format('woff2');
  unicode-range: U+0100-024F, U+0259, U+1E00-1EFF, U+2020, U+20A0-20AB, U+20AD-20CF, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Lato';
  font-style: normal;
  font-weight: 400;
  src: local('Lato Regular'), local('Lato-Regular'), url(https://fonts.gstatic.com/s/lato/v15/S6uyw4BMUTPHjx4wXiWtFCc.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}
/* latin-ext */
@font-face {
  font-family: 'Lato';
  font-style: normal;
  font-weight: 700;
  src: local('Lato Bold'), local('Lato-Bold'), url(https://fonts.gstatic.com/s/lato/v15/S6u9w4BMUTPHh6UVSwaPGQ3q5d0N7w.woff2) format('woff2');
  unicode-range: U+0100-024F, U+0259, U+1E00-1EFF, U+2020, U+20A0-20AB, U+20AD-20CF, U+2113, U+2C60-2C7F, U+A720-A7FF;
}
/* latin */
@font-face {
  font-family: 'Lato';
  font-style: normal;
  font-weight: 700;
  src: local('Lato Bold'), local('Lato-Bold'), url(https://fonts.gstatic.com/s/lato/v15/S6u9w4BMUTPHh6UVSwiPGQ3q5d0.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

/* ===== Light mode (default) ===== */
:root {
  --bg: #ffffff;
  --bg-secondary: #f8f9fa;
  --text: #222222;
  --text-secondary: #666666;
  --link: #1772d0;
  --link-hover: #f09228;
  --highlight-bg: #ffffd0;
  --toggle-bg: #e0e0e0;
  --nav-bg: #ffffff;
  --nav-border: #e0e0e0;
  --nav-text: #555555;
  --nav-active: #1772d0;
  --card-bg: #ffffff;
  --card-border: #e8e8e8;
  --card-hover: #f5f8ff;
  --badge-bg: #e8f0fe;
  --badge-text: #1772d0;
  --badge-accent-bg: #fff3e0;
  --badge-accent-text: #e65100;
  --tag-bg: #f0f0f0;
  --tag-text: #444444;
  --section-heading-border: #1772d0;
  --pub-title: #1a1a1a;
  --pub-authors: #555555;
  --pub-venue: #1772d0;
}

/* ===== Dark mode ===== */
[data-theme="dark"] {
  --bg: #1a1a2e;
  --bg-secondary: #16213e;
  --text: #e0e0e0;
  --text-secondary: #aaaaaa;
  --link: #6db3f2;
  --link-hover: #f09228;
  --highlight-bg: #2a2a4a;
  --toggle-bg: #444466;
  --nav-bg: #1a1a2e;
  --nav-border: #2a2a4a;
  --nav-text: #aaaaaa;
  --nav-active: #6db3f2;
  --card-bg: #16213e;
  --card-border: #2a2a4a;
  --card-hover: #1e2d4a;
  --badge-bg: #1e2d4a;
  --badge-text: #6db3f2;
  --badge-accent-bg: #3a2a1a;
  --badge-accent-text: #ffb74d;
  --tag-bg: #2a2a4a;
  --tag-text: #cccccc;
  --section-heading-border: #6db3f2;
  --pub-title: #f0f0f0;
  --pub-authors: #aaaaaa;
  --pub-venue: #6db3f2;
}

/* ===== Base ===== */
body {
  background-color: var(--bg);
  color: var(--text);
  transition: background-color 0.3s, color 0.3s;
  margin: 0;
}

a {
  color: var(--link);
  text-decoration: none;
}

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

body, td, th, tr, p, a {
  font-family: 'Lato', Verdana, Helvetica, sans-serif;
  font-size: 14px;
}

strong {
  font-family: 'Lato', Verdana, Helvetica, sans-serif;
  font-size: 14px;
}

.name {
  padding-top: 20px;
  margin: 0;
  font-family: 'Lato', Verdana, Helvetica, sans-serif;
  font-size: 32px;
}

/* ===== Section headings ===== */
.section-heading {
  margin: 0 0 16px 0;
  padding-bottom: 8px;
  font-weight: 700;
  font-family: 'Lato', Verdana, Helvetica, sans-serif;
  font-size: 22px;
  color: var(--text);
  border-bottom: 3px solid var(--section-heading-border);
  display: inline-block;
}

/* ===== Navigation bar ===== */
.nav-bar {
  position: sticky;
  top: 0;
  z-index: 999;
  background: var(--nav-bg);
  border-bottom: 1px solid var(--nav-border);
  transition: background 0.3s, border-color 0.3s;
}

.nav-inner {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  padding: 0 16px;
  gap: 4px;
  overflow-x: auto;
}

.nav-link {
  display: inline-block;
  padding: 12px 14px;
  font-size: 13px;
  font-weight: 600;
  color: var(--nav-text);
  text-decoration: none;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}

.nav-link:hover {
  color: var(--nav-active);
}

.nav-link.active {
  color: var(--nav-active);
  border-bottom-color: var(--nav-active);
}

/* ===== News cards ===== */
.news-list {
  list-style: none;
  padding: 0;
  margin: 12px 0 0 0;
}

.news-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 14px 16px;
  border: 1px solid var(--card-border);
  border-radius: 8px;
  margin-bottom: 10px;
  background: var(--card-bg);
  transition: background 0.2s, border-color 0.2s;
}

.news-item:hover {
  background: var(--card-hover);
}

.news-date {
  flex-shrink: 0;
  background: var(--badge-bg);
  color: var(--badge-text);
  font-size: 12px;
  font-weight: 700;
  padding: 6px 10px;
  border-radius: 6px;
  min-width: 80px;
  text-align: center;
  white-space: nowrap;
}

.news-text {
  font-size: 14px;
  line-height: 1.5;
  color: var(--text);
}

/* ===== Research interest tags ===== */
.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 12px 0 0 0;
  padding: 0;
  list-style: none;
}

.tag-item {
  display: inline-block;
  background: var(--tag-bg);
  color: var(--tag-text);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  transition: background 0.2s, color 0.2s;
}

.tag-item:hover {
  background: var(--badge-bg);
  color: var(--badge-text);
}

/* ===== Publication cards ===== */
.pub-list {
  padding: 0;
  margin: 0;
}

.pub-card {
  padding: 16px 18px;
  border: 1px solid var(--card-border);
  border-radius: 8px;
  margin-bottom: 12px;
  background: var(--card-bg);
  transition: background 0.2s, border-color 0.2s;
}

.pub-card:hover {
  background: var(--card-hover);
}

.pub-title {
  font-family: 'Lato', Verdana, Helvetica, sans-serif;
  font-size: 15px;
  font-weight: 700;
  color: var(--pub-title);
  line-height: 1.4;
}

.pub-authors {
  font-size: 13px;
  color: var(--pub-authors);
  margin-top: 4px;
  line-height: 1.5;
}

.pub-venue {
  display: inline-block;
  margin-top: 6px;
  background: var(--badge-bg);
  color: var(--pub-venue);
  font-size: 12px;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 4px;
}

.pub-links {
  margin-top: 8px;
  font-size: 13px;
}

.pub-links a {
  margin-right: 6px;
}

/* ===== Education cards ===== */
.edu-card {
  padding: 16px 18px;
  border: 1px solid var(--card-border);
  border-radius: 8px;
  margin-bottom: 10px;
  background: var(--card-bg);
  transition: background 0.2s, border-color 0.2s;
}

.edu-card:hover {
  background: var(--card-hover);
}

.edu-degree {
  font-size: 15px;
  font-weight: 700;
  color: var(--pub-title);
}

.edu-school {
  font-size: 13px;
  color: var(--pub-authors);
  margin-top: 2px;
}

.edu-year {
  display: inline-block;
  margin-top: 6px;
  background: var(--badge-bg);
  color: var(--badge-text);
  font-size: 12px;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
}

/* ===== Experience cards ===== */
.exp-subheading {
  font-size: 15px;
  font-weight: 700;
  color: var(--pub-title);
  margin: 16px 0 8px 0;
}

.exp-list {
  padding: 0;
  margin: 0;
  list-style: none;
}

.exp-item {
  padding: 10px 14px;
  border: 1px solid var(--card-border);
  border-radius: 6px;
  margin-bottom: 6px;
  background: var(--card-bg);
  font-size: 13px;
  line-height: 1.5;
  transition: background 0.2s;
}

.exp-item:hover {
  background: var(--card-hover);
}

.exp-item .exp-label {
  color: var(--text-secondary);
}

/* ===== Achievement cards ===== */
.achievement-list {
  padding: 0;
  margin: 12px 0 0 0;
  list-style: none;
}

.achievement-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 14px 16px;
  border: 1px solid var(--card-border);
  border-radius: 8px;
  margin-bottom: 10px;
  background: var(--card-bg);
  transition: background 0.2s, border-color 0.2s;
}

.achievement-item:hover {
  background: var(--card-hover);
}

.achievement-icon {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  background: var(--badge-accent-bg);
  color: var(--badge-accent-text);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
}

.achievement-text {
  font-size: 14px;
  line-height: 1.5;
  color: var(--text);
}

/* ===== Theme toggle button ===== */
.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: none;
  cursor: pointer;
  background: var(--toggle-bg);
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  transition: background 0.3s, transform 0.2s;
  z-index: 1000;
}

.theme-toggle:hover {
  transform: scale(1.1);
}

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  transition: opacity 0.3s;
}

[data-theme="dark"] .theme-toggle .icon-sun { display: none; }
[data-theme="light"] .theme-toggle .icon-moon,
:not([data-theme]) .theme-toggle .icon-moon { display: none; }
:not([data-theme]) .theme-toggle .icon-sun { display: inline; }

/* ===== Smooth scroll ===== */
html {
  scroll-behavior: smooth;
  scroll-padding-top: 56px;
}