:root {
  --ink: #17231f;
  --muted: #63716c;
  --paper: #f6f3ea;
  --surface: #fffdf7;
  --line: rgba(23, 35, 31, 0.15);
  --green: #174f3d;
  --green-soft: #dce9de;
  --gold: #ba8744;
  --shadow: 0 22px 60px rgba(32, 48, 42, 0.10);
  --serif: "Iowan Old Style", "Palatino Linotype", "Noto Serif SC", "Songti SC", serif;
  --sans: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 88% 5%, rgba(186, 135, 68, 0.11), transparent 24rem),
    var(--paper);
  font-family: var(--sans);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
img, video, iframe { max-width: 100%; height: auto; }

.skip-link {
  position: fixed;
  z-index: 100;
  top: 12px;
  left: 12px;
  padding: 8px 12px;
  color: white;
  background: var(--green);
  transform: translateY(-150%);
}
.skip-link:focus { transform: none; }

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  border-bottom: 1px solid var(--line);
  background: rgba(246, 243, 234, 0.91);
  backdrop-filter: blur(14px);
}
.header-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  width: min(1240px, calc(100% - 40px));
  min-height: 76px;
  margin: auto;
}
.brand {
  display: inline-flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}
.brand-mark {
  display: grid;
  width: 40px;
  height: 40px;
  place-items: center;
  border-radius: 50%;
  color: var(--paper);
  background: var(--green);
  font: italic 27px/1 Georgia, serif;
}
.brand strong { display: block; font-family: var(--serif); font-size: 17px; line-height: 1.25; }
.brand small { display: block; color: var(--muted); font-size: 8px; letter-spacing: 0.13em; }
.site-nav {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 5px;
  margin-left: auto;
}
.site-nav a {
  padding: 7px 8px;
  border-radius: 7px;
  color: #43504b;
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
}
.site-nav a:hover, .site-nav a:focus-visible { color: var(--green); background: rgba(23, 79, 61, 0.08); }
.nav-toggle { display: none; }

.section-shell, .article-shell { width: min(1120px, calc(100% - 40px)); margin-inline: auto; }
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.22fr) minmax(300px, 0.78fr);
  gap: clamp(36px, 7vw, 110px);
  align-items: center;
  width: min(1120px, calc(100% - 40px));
  min-height: 650px;
  margin: auto;
  padding: 86px 0 96px;
}
.eyebrow { margin: 0 0 13px; color: var(--gold); font-size: 11px; font-weight: 750; letter-spacing: 0.2em; }
.hero h1, .archive-hero h1, .article-header h1, .not-found h1 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 600;
  line-height: 1.13;
  letter-spacing: -0.035em;
}
.hero h1 { font-size: clamp(46px, 6.6vw, 82px); }
.hero-lead { max-width: 650px; margin: 27px 0 0; color: #50605a; font-size: 17px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.primary-button, .secondary-button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border: 1px solid var(--green);
  border-radius: 999px;
  cursor: pointer;
  font-weight: 650;
  text-decoration: none;
}
.primary-button { color: white; background: var(--green); }
.primary-button:hover { background: #0f3e2f; }
.secondary-button { color: var(--green); background: transparent; }
.secondary-button:hover { background: rgba(23, 79, 61, 0.07); }
.hero-aside {
  position: relative;
  padding: 34px;
  border: 1px solid var(--line);
  border-radius: 2px 56px 2px 2px;
  background: rgba(255, 253, 247, 0.72);
  box-shadow: var(--shadow);
}
.hero-aside::before {
  position: absolute;
  width: 95px;
  height: 95px;
  border: 1px solid rgba(186, 135, 68, 0.55);
  border-radius: 50%;
  content: "";
  inset: -25px -25px auto auto;
}
.formula { display: block; padding: 42px 8px 50px; font: italic 38px/1.2 Georgia, serif; text-align: center; }
.hero-aside dl { margin: 0; border-top: 1px solid var(--line); }
.hero-aside dl div { display: grid; grid-template-columns: 100px 1fr; align-items: baseline; padding: 16px 0; border-bottom: 1px solid var(--line); }
.hero-aside dt { color: var(--green); font-family: var(--serif); font-size: 25px; }
.hero-aside dd { margin: 0; color: var(--muted); font-size: 13px; }

.subject-section, .latest-section { padding: 90px 0; }
.subject-section { border-top: 1px solid var(--line); }
.latest-section { padding-top: 20px; }
.section-heading { display: grid; grid-template-columns: 1fr minmax(260px, 0.48fr); gap: 40px; align-items: end; margin-bottom: 34px; }
.section-heading h2 { margin: 0; font-family: var(--serif); font-size: clamp(34px, 5vw, 50px); font-weight: 600; }
.section-heading > p { margin: 0; color: var(--muted); }
.subject-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 12px; }
.subject-card {
  display: flex;
  min-height: 185px;
  flex-direction: column;
  padding: 22px;
  border: 1px solid var(--line);
  background: rgba(255, 253, 247, 0.55);
  text-decoration: none;
  transition: transform 160ms ease, background 160ms ease;
}
.subject-card:hover { background: var(--surface); transform: translateY(-3px); }
.subject-card strong { margin: auto 0 9px; font-family: var(--serif); font-size: 23px; }
.subject-card > span:last-child { color: var(--muted); font-size: 12px; line-height: 1.55; }
.subject-count { color: var(--gold); font-size: 11px; letter-spacing: 0.08em; }
.post-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.post-card { display: flex; min-height: 260px; overflow: hidden; flex-direction: column; border: 1px solid var(--line); background: rgba(255, 253, 247, 0.58); }
.post-card-media { display: block; aspect-ratio: 16 / 7; overflow: hidden; border-bottom: 1px solid var(--line); background: var(--green-soft); }
.post-card-media img { width: 100%; height: 100%; object-fit: cover; transition: transform 240ms ease; }
.post-card:hover .post-card-media img { transform: scale(1.025); }
.post-card-body { display: flex; flex: 1; flex-direction: column; padding: clamp(24px, 4vw, 36px); }
.post-card h3 { margin: 18px 0 13px; font-family: var(--serif); font-size: 26px; font-weight: 600; line-height: 1.35; }
.post-card h3 a { text-decoration: none; }
.post-card h3 a:hover { color: var(--green); }
.post-card-body > p { margin: 0 0 24px; color: var(--muted); }
.post-meta { display: flex; flex-wrap: wrap; gap: 7px; align-items: center; color: var(--muted); font-size: 12px; }
.post-meta time { margin-right: 5px; font-variant-numeric: tabular-nums; }
.chip { padding: 2px 8px; border-radius: 999px; color: var(--green); background: var(--green-soft); text-decoration: none; }
.read-more { margin-top: auto; color: var(--green); font-weight: 650; text-decoration: none; }
.center-action { display: flex; justify-content: center; margin-top: 30px; }

.archive-hero { padding: 90px 0 50px; }
.archive-hero h1 { margin-top: 20px; font-size: clamp(48px, 7vw, 76px); }
.archive-hero > p:last-child { color: var(--muted); }
.archive-page main > .section-shell:last-child { padding-bottom: 100px; }
.back-link { color: var(--green); font-size: 13px; font-weight: 650; text-decoration: none; }

.article-shell { max-width: 1050px; padding: 80px 0 110px; }
.article-header { max-width: 850px; margin: auto; padding-bottom: 52px; border-bottom: 1px solid var(--line); }
.article-header .post-meta { margin-top: 45px; }
.article-header h1 { margin-top: 20px; font-size: clamp(43px, 7vw, 72px); }
.article-header > p { max-width: 700px; margin: 24px 0 0; color: var(--muted); font-size: 17px; }
.article-layout { display: grid; grid-template-columns: 112px minmax(0, 720px); gap: 58px; justify-content: center; padding-top: 56px; }
.article-rail { color: #87918d; font-size: 10px; letter-spacing: 0.12em; writing-mode: vertical-rl; }
.article-rail span { display: inline-block; height: 90px; margin: 12px 0; border-left: 1px solid var(--line); }
.article-content { min-width: 0; font-family: var(--serif); font-size: 17px; line-height: 1.9; overflow-wrap: anywhere; }
.article-content h2, .article-content h3, .article-content h4 { margin: 2.1em 0 0.75em; color: var(--ink); line-height: 1.35; }
.article-content h2 { font-size: 1.7em; }
.article-content h3 { font-size: 1.35em; }
.article-content p { margin: 1.05em 0; }
.article-content a { color: #0f6046; }
.article-content blockquote { margin: 1.7em 0; padding: 0.3em 0 0.3em 1.4em; border-left: 3px solid var(--gold); color: #51605a; }
.article-content pre, .article-content code { font-family: "SFMono-Regular", Consolas, monospace; }
.article-content pre { max-width: 100%; padding: 18px; overflow: auto; border-radius: 8px; color: #edf3ef; background: #17231f; font-size: 13px; line-height: 1.65; }
.article-content :not(pre) > code { padding: 0.15em 0.35em; border-radius: 4px; background: rgba(23, 79, 61, 0.09); font-size: 0.88em; }
.article-content table { display: block; max-width: 100%; overflow-x: auto; border-collapse: collapse; }
.article-content th, .article-content td { padding: 8px 10px; border: 1px solid var(--line); }
.article-content img { display: block; margin: 2em auto; border-radius: 4px; box-shadow: 0 12px 35px rgba(24, 38, 32, 0.1); }
.article-content .MathJax_Display { max-width: 100%; overflow-x: auto; overflow-y: hidden; }
.math-preamble { display: none; }
.post-navigation { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; max-width: 850px; margin: 70px auto 0; }
.post-navigation a { min-height: 120px; padding: 22px; border: 1px solid var(--line); background: rgba(255, 253, 247, 0.55); text-decoration: none; }
.post-navigation span { display: block; margin-bottom: 10px; color: var(--muted); font-size: 11px; }
.post-navigation strong { font-family: var(--serif); font-size: 17px; }
.page-shell .article-content { max-width: 720px; margin: 50px auto 0; }
.static-notice { margin-top: 36px; padding: 18px 20px; border-left: 3px solid var(--gold); background: rgba(186, 135, 68, 0.1); }

.search-dialog {
  width: min(760px, calc(100% - 28px));
  max-height: min(82vh, 820px);
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 18px;
  color: var(--ink);
  background: var(--surface);
  box-shadow: 0 30px 100px rgba(12, 28, 22, 0.3);
}
.search-dialog::backdrop { background: rgba(17, 29, 24, 0.58); backdrop-filter: blur(4px); }
.search-head { display: flex; align-items: start; justify-content: space-between; gap: 20px; }
.search-head h2 { margin: 0; font-family: var(--serif); font-size: 32px; }
.close-button { width: 38px; height: 38px; border: 0; border-radius: 50%; cursor: pointer; color: var(--green); background: var(--green-soft); font-size: 25px; }
.search-field { display: block; margin-top: 24px; }
.search-field input { width: 100%; padding: 13px 15px; border: 1px solid var(--line); border-radius: 9px; color: var(--ink); background: white; outline: none; }
.search-field input:focus { border-color: var(--green); box-shadow: 0 0 0 3px rgba(23, 79, 61, 0.12); }
.search-status { color: var(--muted); font-size: 12px; }
.search-results { max-height: 50vh; overflow: auto; }
.search-result { display: block; padding: 15px 4px; border-top: 1px solid var(--line); text-decoration: none; }
.search-result strong { display: block; font-family: var(--serif); font-size: 18px; }
.search-result span { color: var(--muted); font-size: 12px; }
.search-empty { padding: 40px 0; color: var(--muted); text-align: center; }

.site-footer { display: flex; justify-content: space-between; gap: 20px; width: min(1120px, calc(100% - 40px)); margin: auto; padding: 32px 0 45px; border-top: 1px solid var(--line); color: var(--muted); font-size: 12px; }
.site-footer p { margin: 0; }
.not-found { min-height: 70vh; padding: 120px 0; text-align: center; }
.not-found h1 { margin-bottom: 22px; font-size: clamp(45px, 7vw, 72px); }
.not-found > p:not(.eyebrow) { margin-bottom: 30px; color: var(--muted); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

@media (max-width: 1040px) {
  .nav-toggle { display: inline-flex; margin-left: auto; padding: 7px 13px; border: 1px solid var(--line); border-radius: 999px; color: var(--green); background: transparent; }
  .site-nav { position: absolute; top: calc(100% + 1px); right: 20px; left: 20px; display: none; max-height: calc(100vh - 100px); padding: 12px; overflow: auto; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); box-shadow: var(--shadow); }
  .site-nav.is-open { display: grid; grid-template-columns: repeat(3, 1fr); }
  .site-nav a { padding: 10px; }
  .subject-grid { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 760px) {
  .header-inner { width: min(100% - 28px, 1120px); min-height: 68px; }
  .brand small { display: none; }
  .site-nav { right: 14px; left: 14px; }
  .site-nav.is-open { grid-template-columns: repeat(2, 1fr); }
  .hero { grid-template-columns: 1fr; min-height: auto; padding: 65px 0 75px; }
  .hero h1 { font-size: clamp(42px, 13.2vw, 67px); }
  .hero-aside { padding: 24px; }
  .formula { padding: 28px 0 35px; font-size: 32px; }
  .section-heading { grid-template-columns: 1fr; gap: 14px; }
  .subject-grid { grid-template-columns: repeat(2, 1fr); }
  .subject-card { min-height: 160px; padding: 18px; }
  .post-grid { grid-template-columns: 1fr; }
  .article-shell { width: min(100% - 30px, 1050px); padding-top: 55px; }
  .article-header { padding-bottom: 38px; }
  .article-header h1 { font-size: clamp(38px, 12vw, 58px); }
  .article-layout { display: block; padding-top: 40px; }
  .article-rail { display: none; }
  .article-content { font-size: 16px; line-height: 1.85; }
  .post-navigation { grid-template-columns: 1fr; }
  .search-dialog { padding: 22px 18px; }
  .site-footer { display: block; }
  .site-footer p + p { margin-top: 8px; }
}

@media (max-width: 430px) {
  .subject-grid { grid-template-columns: 1fr; }
  .subject-card { min-height: 135px; }
  .hero-actions > * { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}


/* Preserved mathematical article styles from WordPress. */
.latex_lem, .latex_cor, .latex_prop, .latex_rem{
    background-color: rgba(114, 205, 136, 0.1);
    padding-top: 0.2cm;
    padding-bottom: 0.2cm;
    padding-left: 5pt;
    margin: 5pt;
}
.latex_defn {
    background-color: floralwhite;
    padding-top: 0.2cm;
    padding-bottom: 0.2cm;
    padding-left: 5pt;
    margin: 5pt;
}

.latex_thm{
    background-color: rgb(248, 249, 250);
    padding-top: 0.2cm;
    padding-bottom: 0.2cm;
    padding-left: 5pt;
    margin: 5pt;
}

.latex_em, .latex_it{
  font-style: italic;
}
.latex_bf{
  font-weight:bold;
}
.bibtex_title{
  font-weight:bold;
  color: #004b33;
}
a.bibtex_title{
  text-decoration: none;
}
.latex_proof {
  position: relative; /* 确保父容器相对定位 */
  padding-right: 1.5em; /* 确保内容不会被符号遮挡 */
}

.latex_proof::after {
  content: "\220E";
  color: gray;
  font-size: 1.2em;
  position: absolute;
  right: 0;
  bottom: 0;
}

.latex_flushright {
  text-align: right;
}
.latex_leftright {
  text-align: left;
}
.latex_quotation {
  border-left: 2px solid #333; /* Left border for the quotation */
  padding-left: 10px; /* Left padding to separate text from the border */
  margin: 10px 0; /* Margin around the quotation */
  font-style: italic; /* Italics for the text */
  color: #666; /* Text color for the quotation */
}