:root {
  --ink: #14241f;
  --ink-soft: #3a5048;
  --muted: #6b7f76;
  --paper: #f3f6f4;
  --paper-deep: #e4ebe6;
  --sage: #5f8576;
  --sage-deep: #3d6557;
  --mist: #cdd9d2;
  --accent: #c4784a;
  --line: rgba(20, 36, 31, 0.12);
  --glow: rgba(95, 133, 118, 0.35);
  --font-brand: "Cormorant Garamond", "Songti SC", "Noto Serif SC", Georgia, serif;
  --font-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", Georgia, serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --max: 1080px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
  border: 0;
  background: none;
  cursor: pointer;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 100;
  padding: 0.6rem 1rem;
  background: var(--ink);
  color: var(--paper);
}

.skip-link:focus {
  top: 1rem;
}

/* —— Nav —— */
.site-nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.1rem clamp(1.2rem, 4vw, 3rem);
  transition: background 0.35s var(--ease), backdrop-filter 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

.site-nav.is-scrolled {
  background: rgba(243, 246, 244, 0.88);
  backdrop-filter: blur(14px);
  box-shadow: 0 1px 0 var(--line);
}

.nav-brand {
  font-family: var(--font-brand);
  font-size: 1.55rem;
  font-weight: 500;
  font-style: italic;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.5vw, 2rem);
  list-style: none;
}

.nav-links a {
  font-size: 0.92rem;
  color: var(--ink-soft);
  transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--sage-deep);
}

.nav-toggle {
  display: none;
  width: 2.5rem;
  height: 2.5rem;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 0.4rem;
}

.nav-toggle span {
  display: block;
  width: 1.1rem;
  height: 1.5px;
  background: var(--ink);
  position: relative;
}

.nav-toggle span::before,
.nav-toggle span::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 100%;
  background: inherit;
}

.nav-toggle span::before { top: -5px; }
.nav-toggle span::after { top: 5px; }

/* —— Hero —— */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  align-items: end;
  overflow: hidden;
  color: #f7faf8;
}

.hero-visual {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(14, 28, 24, 0.25) 0%, rgba(14, 28, 24, 0.55) 45%, rgba(14, 28, 24, 0.88) 100%),
    radial-gradient(ellipse 80% 60% at 70% 20%, rgba(95, 133, 118, 0.45), transparent 60%),
    radial-gradient(ellipse 50% 40% at 15% 80%, rgba(196, 120, 74, 0.22), transparent 55%),
    linear-gradient(135deg, #1c3a32 0%, #243f38 38%, #35584c 72%, #4a6b5c 100%);
  animation: heroDrift 22s ease-in-out infinite alternate;
}

.hero-visual::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(
      -12deg,
      transparent 0,
      transparent 38px,
      rgba(255, 255, 255, 0.02) 38px,
      rgba(255, 255, 255, 0.02) 39px
    );
  opacity: 0.7;
}

.hero-ornament {
  position: absolute;
  right: clamp(-4%, 2vw, 8%);
  top: 12%;
  width: min(48vw, 420px);
  height: min(55vh, 520px);
  opacity: 0.55;
  animation: ornamentFloat 14s var(--ease) infinite alternate;
}

.hero-content {
  position: relative;
  z-index: 2;
  width: min(100% - 2.4rem, var(--max));
  margin: 0 auto;
  padding: 7rem 0 5.5rem;
}

.hero-brand {
  font-family: var(--font-brand);
  font-size: clamp(3.4rem, 9vw, 6.4rem);
  font-weight: 500;
  font-style: italic;
  line-height: 0.95;
  letter-spacing: 0.02em;
  margin-bottom: 1.4rem;
  opacity: 0;
  transform: translateY(1.2rem);
  animation: riseIn 1s var(--ease) 0.15s forwards;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 3vw, 1.85rem);
  font-weight: 500;
  letter-spacing: 0.08em;
  margin-bottom: 0.85rem;
  opacity: 0;
  transform: translateY(1.2rem);
  animation: riseIn 1s var(--ease) 0.35s forwards;
}

.hero-lead {
  max-width: 28rem;
  font-size: 1.02rem;
  color: rgba(247, 250, 248, 0.82);
  margin-bottom: 2rem;
  opacity: 0;
  transform: translateY(1.2rem);
  animation: riseIn 1s var(--ease) 0.5s forwards;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  opacity: 0;
  transform: translateY(1.2rem);
  animation: riseIn 1s var(--ease) 0.65s forwards;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.85rem;
  padding: 0.65rem 1.4rem;
  border-radius: 0.2rem;
  font-size: 0.95rem;
  transition: transform 0.25s var(--ease), background 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: #f3f6f4;
  color: var(--ink);
}

.btn-primary:hover {
  background: #fff;
}

.btn-ghost {
  border: 1px solid rgba(243, 246, 244, 0.45);
  color: #f3f6f4;
}

.btn-ghost:hover {
  border-color: #f3f6f4;
  background: rgba(243, 246, 244, 0.08);
}

@keyframes riseIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes heroDrift {
  from { transform: scale(1) translate(0, 0); }
  to { transform: scale(1.06) translate(-1.5%, 1%); }
}

@keyframes ornamentFloat {
  from { transform: translateY(0) rotate(-2deg); }
  to { transform: translateY(18px) rotate(2deg); }
}

/* —— Sections —— */
.section {
  width: min(100% - 2.4rem, var(--max));
  margin: 0 auto;
  padding: clamp(3.5rem, 8vw, 5.5rem) 0;
}

.section-head {
  max-width: 36rem;
  margin-bottom: 2.4rem;
}

.section-kicker {
  display: inline-block;
  margin-bottom: 0.65rem;
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--sage);
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3.4vw, 2.15rem);
  font-weight: 600;
  line-height: 1.35;
  margin-bottom: 0.75rem;
}

.section-desc {
  color: var(--ink-soft);
  font-size: 1.02rem;
}

.reveal {
  opacity: 0;
  transform: translateY(1.4rem);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Purpose strip */
.purpose {
  background:
    linear-gradient(180deg, var(--paper) 0%, var(--paper-deep) 100%);
  border-block: 1px solid var(--line);
}

.purpose-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.purpose-item {
  padding: 0.4rem 0;
}

.purpose-item h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.55rem;
}

.purpose-item p {
  color: var(--ink-soft);
  font-size: 0.96rem;
}

.purpose-num {
  display: block;
  margin-bottom: 0.85rem;
  font-family: var(--font-brand);
  font-style: italic;
  font-size: 1.5rem;
  color: var(--sage);
}

/* Entry list (not cards — editorial list) */
.entry-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.entry {
  display: grid;
  grid-template-columns: 7rem 1fr auto;
  gap: 1.2rem;
  align-items: baseline;
  padding: 1.35rem 0;
  border-bottom: 1px solid var(--line);
  transition: padding-left 0.3s var(--ease), background 0.3s ease;
}

.entry:hover {
  padding-left: 0.5rem;
}

.entry-meta {
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  color: var(--sage);
}

.entry h3 {
  font-family: var(--font-display);
  font-size: 1.18rem;
  font-weight: 600;
  margin-bottom: 0.35rem;
}

.entry p {
  color: var(--ink-soft);
  font-size: 0.95rem;
}

.entry-arrow {
  color: var(--muted);
  font-size: 1.2rem;
  transition: transform 0.25s var(--ease), color 0.25s ease;
}

.entry:hover .entry-arrow {
  color: var(--sage-deep);
  transform: translateX(4px);
}

/* Quote block */
.quote-band {
  position: relative;
  overflow: hidden;
  background: var(--ink);
  color: #eef3f0;
}

.quote-band .section {
  position: relative;
  z-index: 1;
}

.quote-mark {
  font-family: var(--font-brand);
  font-size: 5rem;
  line-height: 0.6;
  color: var(--sage);
  opacity: 0.7;
  margin-bottom: 1rem;
}

.quote-text {
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 2.6vw, 1.7rem);
  font-weight: 500;
  line-height: 1.65;
  max-width: 40rem;
  margin-bottom: 1.2rem;
}

.quote-attr {
  color: rgba(238, 243, 240, 0.65);
  font-size: 0.92rem;
}

/* Page shell (inner pages) */
.page-hero {
  padding: 7.5rem 0 2.5rem;
  background:
    radial-gradient(ellipse 70% 80% at 100% 0%, rgba(95, 133, 118, 0.16), transparent 55%),
    linear-gradient(180deg, #e8efea 0%, var(--paper) 100%);
  border-bottom: 1px solid var(--line);
}

.page-hero-inner {
  width: min(100% - 2.4rem, var(--max));
  margin: 0 auto;
}

.page-hero .nav-brand {
  display: none;
}

.page-kicker {
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--sage);
  margin-bottom: 0.75rem;
}

.page-title {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 4vw, 2.6rem);
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.page-lead {
  max-width: 34rem;
  color: var(--ink-soft);
  font-size: 1.05rem;
}

/* Knowledge topics as editorial rows */
.topic-list {
  display: grid;
  gap: 1.25rem;
}

.topic {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.2rem;
  padding: 1.4rem 0;
  border-bottom: 1px solid var(--line);
}

.topic:first-child {
  border-top: 1px solid var(--line);
}

.topic-index {
  font-family: var(--font-brand);
  font-style: italic;
  font-size: 1.4rem;
  color: var(--sage);
  min-width: 2.2rem;
}

.topic h2 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
}

.topic p {
  color: var(--ink-soft);
  margin-bottom: 0.7rem;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.tag {
  font-size: 0.78rem;
  color: var(--sage-deep);
  letter-spacing: 0.04em;
}

.tag::before {
  content: "#";
  opacity: 0.5;
  margin-right: 0.1rem;
}

/* Notes */
.notes {
  display: grid;
  gap: 1.75rem;
}

.note {
  padding: 1.6rem 0 1.8rem;
  border-bottom: 1px solid var(--line);
}

.note:first-child {
  border-top: 1px solid var(--line);
}

.note-top {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem 1rem;
  margin-bottom: 0.9rem;
}

.note h2 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
}

.note-cat {
  font-size: 0.82rem;
  color: var(--sage);
  letter-spacing: 0.06em;
}

.note blockquote {
  font-family: var(--font-display);
  font-size: 1.15rem;
  line-height: 1.75;
  color: var(--ink);
  margin-bottom: 0.9rem;
  padding-left: 1rem;
  border-left: 2px solid var(--sage);
}

.note-source {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 0.85rem;
}

.note-thought {
  color: var(--ink-soft);
  font-size: 0.96rem;
}

.note-actions {
  margin-top: 1rem;
}

.btn-small {
  min-height: 2.2rem;
  padding: 0.4rem 0.9rem;
  font-size: 0.85rem;
  border: 1px solid var(--line);
  border-radius: 0.2rem;
  color: var(--ink-soft);
}

.btn-small:hover {
  border-color: var(--sage);
  color: var(--sage-deep);
}

/* Theme rows */
.theme-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
}

.theme {
  padding: 1.6rem 1.4rem 1.6rem 0;
  border-top: 1px solid var(--line);
}

.theme:nth-child(even) {
  padding-left: 1.4rem;
  padding-right: 0;
  border-left: 1px solid var(--line);
}

.theme h2 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.theme p {
  color: var(--ink-soft);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

/* About */
.about-prose {
  max-width: 40rem;
}

.about-prose p {
  color: var(--ink-soft);
  font-size: 1.05rem;
  margin-bottom: 1.1rem;
}

.about-list {
  margin: 1.5rem 0 0;
  padding-left: 1.1rem;
  color: var(--ink-soft);
}

.about-list li {
  margin-bottom: 0.45rem;
}

/* Footer — ICP critical */
.site-footer {
  margin-top: auto;
  padding: 2.4rem clamp(1.2rem, 4vw, 3rem) 2rem;
  background: #101c18;
  color: rgba(238, 243, 240, 0.72);
  text-align: center;
}

.footer-brand {
  font-family: var(--font-brand);
  font-style: italic;
  font-size: 1.35rem;
  color: #f3f6f4;
  margin-bottom: 0.55rem;
}

.footer-copy {
  font-size: 0.88rem;
  margin-bottom: 0.85rem;
}

.beian-link {
  display: inline-block;
  font-size: 0.9rem;
  color: rgba(238, 243, 240, 0.85);
  letter-spacing: 0.04em;
  border-bottom: 1px solid rgba(238, 243, 240, 0.28);
  padding-bottom: 1px;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.beian-link:hover {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.7);
}

/* Layout helper */
.page {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.page-main {
  flex: 1;
}

/* Mobile */
@media (max-width: 800px) {
  .nav-toggle {
    display: grid;
  }

  .nav-links {
    position: fixed;
    inset: 0 0 auto;
    top: 4.2rem;
    margin: 0 1rem;
    padding: 1rem;
    flex-direction: column;
    align-items: stretch;
    gap: 0.2rem;
    background: rgba(243, 246, 244, 0.96);
    border: 1px solid var(--line);
    border-radius: 0.4rem;
    box-shadow: 0 12px 40px rgba(20, 36, 31, 0.12);
    transform: translateY(-0.5rem);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s var(--ease);
  }

  .nav-links.is-open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .nav-links a {
    padding: 0.7rem 0.6rem;
  }

  .purpose-grid {
    grid-template-columns: 1fr;
    gap: 1.8rem;
  }

  .entry {
    grid-template-columns: 1fr;
    gap: 0.35rem;
  }

  .entry-arrow {
    display: none;
  }

  .theme-grid {
    grid-template-columns: 1fr;
  }

  .theme,
  .theme:nth-child(even) {
    padding: 1.4rem 0;
    border-left: 0;
  }

  .hero-ornament {
    opacity: 0.28;
    width: 70vw;
    right: -18%;
  }
}

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

  .reveal {
    opacity: 1;
    transform: none;
  }

  .hero-brand,
  .hero-title,
  .hero-lead,
  .hero-actions {
    opacity: 1;
    transform: none;
  }
}