:root {
  --paper: #f4f1e8;
  --paper-soft: rgba(244, 241, 232, 0.84);
  --ink: #11110f;
  --ink-100: #11110f;
  --ink-60: #55534a;
  --ink-30: rgba(17, 17, 15, 0.28);
  --lime: #c8ff00;
  --on-lime: #11110f;
  --on-lime-accent: #2447ff;
  --blue: #2447ff;
  --grid: #d8d4c8;
  --muted: #69675f;
  --white: #fffef8;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  background: var(--paper);
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink-100);
  font-family: var(--font-geist-sans), "Noto Sans SC", "Microsoft YaHei", sans-serif;
}

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

::selection {
  background: var(--blue);
  color: white;
}

.site-header {
  position: absolute;
  z-index: 20;
  top: 0;
  left: 0;
  display: flex;
  width: 100%;
  height: 104px;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(24px, 4.45vw, 72px);
  border-bottom: 1px solid var(--ink-30);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  text-transform: uppercase;
}

.brand-logo {
  width: 70px;
  height: 70px;
  object-fit: contain;
}

.brand-divider {
  width: 1px;
  height: 42px;
  background: var(--ink-100);
  transform: rotate(14deg);
}

.brand-name {
  font-size: 12px;
  font-weight: 750;
  letter-spacing: 0.02em;
  line-height: 1.12;
  max-width: 6.5em;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: clamp(24px, 3vw, 52px);
  font-size: 15px;
  font-weight: 700;
}

.main-nav a {
  position: relative;
  padding: 12px 0;
}

.main-nav a::after {
  position: absolute;
  bottom: 2px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--blue);
  content: "";
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 220ms ease;
}

.main-nav a:hover::after,
.main-nav a:focus-visible::after,
.main-nav a.active::after {
  transform: scaleX(1);
  transform-origin: left;
}

.main-nav .nav-join {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 12px 16px;
  background: var(--lime);
  color: var(--on-lime);
  border: 1px solid var(--on-lime);
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.main-nav .nav-join:hover,
.main-nav .nav-join:focus-visible {
  transform: translate(-2px, -2px);
  box-shadow: 4px 4px 0 var(--blue);
}

.main-nav .nav-join::after,
.main-nav .nav-ai::after {
  display: none;
}

.nav-join-arrow {
  width: 14px;
  height: 14px;
}

.main-nav .nav-ai {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  color: var(--blue);
}

.nav-ai-arrow {
  width: 12px;
  height: 12px;
}

.hero {
  position: relative;
  display: grid;
  min-height: calc(100dvh - 104px);
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  grid-template-rows: 1fr auto;
  overflow: hidden;
  padding: 0 clamp(24px, 4.45vw, 72px);
  background-color: var(--paper);
  background-image: linear-gradient(rgba(36, 71, 255, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 71, 255, 0.08) 1px, transparent 1px);
  background-size: 128px 128px;
}
.corner-mark {
  position: absolute;
  z-index: 2;
  width: 22px;
  height: 22px;
  border-top: 1px solid var(--ink-100);
  border-left: 1px solid var(--ink-100);
}

.corner-tl {
  top: 24px;
  left: 20px;
}

.corner-br {
  right: 20px;
  bottom: 24px;
  transform: rotate(180deg);
}

.hero-copy {
  position: relative;
  z-index: 5;
  display: flex;
  align-self: center;
  flex-direction: column;
  align-items: flex-start;
  padding: clamp(48px, 6vw, 96px) 0;
}

.eyebrow {
  margin: 0 0 24px;
  color: var(--blue);
  font-family: var(--font-geist-mono), monospace;
  font-size: clamp(13px, 1.2vw, 18px);
  font-weight: 600;
  letter-spacing: 0.11em;
}

.hero h1 {
  max-width: 920px;
  margin: 0;
  color: var(--ink-100);
  font-size: clamp(46px, 4.8vw, 84px);
  font-weight: 900;
  letter-spacing: -0.06em;
  line-height: 1;
}

.hero-intro {
  max-width: 560px;
  margin: 28px 0 0;
  color: var(--ink-60);
  font-size: clamp(16px, 1.4vw, 21px);
  font-weight: 520;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 22px;
  margin-top: 36px;
}

.hero-microcopy {
  margin: 16px 0 0;
  color: var(--ink-60);
  font-size: 13px;
  letter-spacing: 0.02em;
}

.button {
  display: inline-flex;
  min-width: 196px;
  height: 58px;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 0 22px;
  border: 1px solid var(--ink-100);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.03em;
  transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

.button-icon {
  width: 20px;
  height: 20px;
}

.button:hover,
.button:focus-visible {
  transform: translate(-2px, -2px);
}

.button-primary {
  background: var(--lime);
  color: var(--on-lime);
}

.button-primary:hover,
.button-primary:focus-visible {
  box-shadow: 7px 7px 0 var(--blue);
}

.button-ghost {
  background: transparent;
  border-width: 0 0 2px;
}

.button-ghost:hover,
.button-ghost:focus-visible {
  background: rgba(17, 17, 15, 0.06);
}

.hero-visual {
  position: relative;
  z-index: 3;
  min-height: 0;
  align-self: stretch;
  width: 100%;
  height: 100%;
  padding: 24px 0;
  overflow: hidden;
}

.robot-arm {
  position: relative;
  z-index: 2;
  display: block;
  width: 100%;
  height: 100%;
  max-width: 640px;
  max-height: 560px;
  margin: 0 auto;
  object-fit: contain;
  object-position: center;
  mix-blend-mode: normal;
  filter: contrast(1.02);
  pointer-events: none;
  animation: robot-enter 900ms cubic-bezier(0.2, 0.72, 0, 1) both;
}

.blueprint {
  position: absolute;
  z-index: 1;
  bottom: 18%;
  right: 4%;
  width: 180px;
  aspect-ratio: 1;
  border: 1px dashed var(--blue);
  border-radius: 50%;
  color: var(--blue);
  opacity: 0.35;
  animation: rotate-blueprint 26s linear infinite;
  pointer-events: none;
}

.blueprint::before,
.blueprint::after,
.blueprint span {
  position: absolute;
  border: 1px solid currentColor;
  border-radius: 50%;
  content: "";
}

.blueprint::before {
  inset: 24px;
}

.blueprint::after {
  inset: 62px;
}

.blueprint span:nth-child(1) {
  top: 50%;
  right: -28px;
  width: 56px;
  height: 1px;
  border: 0;
  border-top: 1px solid currentColor;
  border-radius: 0;
}

.blueprint span:nth-child(2) {
  top: -24px;
  left: 50%;
  width: 1px;
  height: 220px;
  border: 0;
  border-left: 1px solid currentColor;
  border-radius: 0;
}

.hero-proof {
  position: relative;
  z-index: 8;
  display: grid;
  min-height: 72px;
  grid-column: 1 / -1;
  grid-template-columns: repeat(3, 1fr);
  align-items: center;
  border-top: 1px solid var(--ink-30);
  background: var(--paper-soft);
  font-family: var(--font-geist-mono), monospace;
  font-size: 12px;
  letter-spacing: 0.08em;
}

.hero-proof span {
  border-left: 1px solid var(--grid);
  padding-left: 32px;
}

.hero-proof span:first-child {
  border-left: 0;
  padding-left: 32px;
}

.section {
  padding: 110px clamp(24px, 5.5vw, 88px);
  border-top: 1px solid var(--ink-30);
}

.section-kicker {
  display: grid;
  grid-template-columns: 86px 1fr;
  margin-bottom: 86px;
  color: var(--blue);
  font-family: var(--font-geist-mono), monospace;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
}

.section-kicker span:first-child {
  position: relative;
}

.section-kicker span:first-child::after {
  position: absolute;
  top: 8px;
  left: 32px;
  width: 28px;
  height: 1px;
  background: currentColor;
  content: "";
}

.about-grid {
  display: grid;
  grid-template-columns: 0.82fr 1.18fr;
  gap: 8vw;
}

.about-grid > h2,
.projects-heading h2,
.activities-heading h2,
.section-join h2 {
  margin: 0;
  font-size: clamp(50px, 6.4vw, 98px);
  font-weight: 880;
  letter-spacing: -0.065em;
  line-height: 1.02;
}

.about-grid > h2,
.projects-heading h2 {
  color: var(--ink-100);
}

.activities-heading h2 {
  color: #f4f1e8;
}

.section-join h2 {
  color: var(--on-lime);
}

.about-lead {
  max-width: 760px;
  margin: 0 0 72px;
  color: var(--ink-60);
  font-size: clamp(20px, 2vw, 30px);
  font-weight: 550;
  line-height: 1.6;
}

.principles {
  border-top: 1px solid var(--ink-30);
}

.principles article {
  display: grid;
  grid-template-columns: 106px 0.62fr 1fr;
  gap: 24px;
  align-items: baseline;
  padding: 26px 0;
  border-bottom: 1px solid var(--ink-30);
}

.principles span,
.project-index,
.project-tags,
.project-status,
.activity-grid article > span {
  color: var(--blue);
  font-family: var(--font-geist-mono), monospace;
  font-size: 11px;
  letter-spacing: 0.06em;
}

.principles h3,
.principles p,
.project-row h3,
.project-summary,
.activity-grid h3,
.activity-grid p,
.join-steps h3,
.join-steps p {
  margin: 0;
}

.principles h3 {
  font-size: 18px;
}

.principles p {
  color: var(--ink-60);
  line-height: 1.7;
}

.section-projects {
  background: var(--white);
}

.projects-heading {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(300px, 0.6fr);
  gap: 8vw;
  align-items: end;
  margin-bottom: 88px;
}

.projects-heading h2 {
  max-width: 900px;
}

.projects-heading > p,
.activities-heading > p {
  margin: 0;
  color: var(--ink-60);
  font-size: 18px;
  line-height: 1.8;
}

.project-list {
  border-top: 2px solid var(--ink-30);
}

.project-row {
  display: grid;
  grid-template-columns: 70px 1.1fr 1fr 170px;
  gap: 30px;
  align-items: center;
  min-height: 178px;
  border-bottom: 1px solid var(--ink-30);
  transition: background 200ms ease, padding 200ms ease;
  cursor: pointer;
}

.project-row:hover {
  padding: 0 18px;
  background: var(--lime);
}

.project-row:hover .project-index,
.project-row:hover .project-tags,
.project-row:hover .project-status {
  color: var(--on-lime);
}

.project-row h3 {
  font-size: clamp(26px, 2.8vw, 44px);
  letter-spacing: -0.04em;
}

.project-title-wrap {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.project-tags span + span::before {
  margin-right: 12px;
  content: "/";
}

.project-summary {
  color: var(--ink-60);
  line-height: 1.7;
}

.project-meta {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 22px;
}

.project-status {
  color: var(--ink-60);
}

.project-arrow {
  display: inline-flex;
  color: var(--ink-100);
}

.project-arrow-icon {
  width: 26px;
  height: 26px;
}

.section-activities {
  background: #11110f;
  color: #f4f1e8;
}

.section-kicker-light {
  color: var(--lime);
}

.activities-heading {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 8vw;
  align-items: end;
  margin-bottom: 100px;
}

.activities-heading > p {
  max-width: 560px;
  color: #aeaca4;
}

.activity-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid rgba(244, 241, 232, 0.45);
}

.activity-grid article {
  position: relative;
  min-height: 360px;
  padding: 30px 44px 44px;
  border-right: 1px solid rgba(244, 241, 232, 0.28);
}

.activity-grid article:first-child {
  padding-left: 0;
}

.activity-grid article:last-child {
  border-right: 0;
}

.activity-grid article > span {
  color: var(--lime);
}

.activity-grid h3 {
  margin-top: 86px;
  font-size: clamp(28px, 3vw, 46px);
}

.activity-grid p {
  max-width: 340px;
  margin-top: 22px;
  color: #aeaca4;
  line-height: 1.75;
}

.activity-line {
  position: absolute;
  right: 44px;
  bottom: 44px;
  left: 44px;
  height: 3px;
  background: rgba(244, 241, 232, 0.18);
}

.activity-grid article:first-child .activity-line {
  left: 0;
}

.activity-line::after {
  display: block;
  width: 38%;
  height: 100%;
  background: var(--lime);
  content: "";
  transition: width 400ms ease;
}

.activity-grid article:hover .activity-line::after {
  width: 100%;
}

.section-join {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 9vw;
  min-height: 760px;
  align-items: center;
  background: var(--lime);
}

.wechat-card {
  width: min(100%, 440px);
  justify-self: end;
  border: 2px solid var(--ink-100);
  background: var(--paper);
  box-shadow: 14px 14px 0 var(--blue);
}

.wechat-card-head,
.wechat-card-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 18px;
  font-family: var(--font-geist-mono), monospace;
  font-size: 11px;
  letter-spacing: 0.06em;
}

.wechat-card-head {
  border-bottom: 1px solid var(--ink-100);
}

.wechat-card-scan {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.wechat-card-scan-icon {
  width: 12px;
  height: 12px;
}

.wechat-qr-wrap {
  position: relative;
  padding: 30px;
  background-image: linear-gradient(rgba(36, 71, 255, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 71, 255, 0.08) 1px, transparent 1px);
  background-size: 24px 24px;
}

.wechat-qr-wrap img {
  display: block;
  width: 100%;
  aspect-ratio: 1;
  border: 1px solid var(--ink-100);
  object-fit: cover;
}

.wechat-qr-wrap .corner {
  position: absolute;
  width: 25px;
  height: 25px;
  border-color: var(--blue);
}

.wechat-qr-wrap .corner-a {
  top: 18px;
  left: 18px;
  border-top: 3px solid var(--blue);
  border-left: 3px solid var(--blue);
}

.wechat-qr-wrap .corner-b {
  right: 18px;
  bottom: 18px;
  border-right: 3px solid var(--blue);
  border-bottom: 3px solid var(--blue);
}

.wechat-card-foot {
  border-top: 1px solid var(--ink-100);
}

.wechat-card-foot strong {
  font-size: 18px;
}

.section-join .eyebrow {
  color: var(--on-lime-accent);
}

.join-intro {
  max-width: 720px;
  margin: 38px 0 40px;
  color: var(--on-lime);
  opacity: 0.86;
  font-size: clamp(18px, 1.7vw, 24px);
  font-weight: 550;
  line-height: 1.7;
}

.join-status {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  border: 1px solid var(--on-lime);
  color: var(--on-lime);
  font-family: var(--font-geist-mono), monospace;
  font-size: 13px;
  font-weight: 600;
}

.pulse {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--blue);
  box-shadow: 0 0 0 0 rgba(36, 71, 255, 0.5);
  animation: pulse 2s infinite;
}

.join-placeholder {
  max-width: 610px;
  margin: 18px 0 0;
  color: var(--on-lime);
  font-size: 13px;
  line-height: 1.6;
  opacity: 0.72;
}

footer {
  background: #11110f;
  color: #f4f1e8;
  font-family: var(--font-geist-mono), monospace;
  font-size: 11px;
  letter-spacing: 0.08em;
  padding: 0 clamp(24px, 5.5vw, 88px);
}

.footer-top {
  display: grid;
  grid-template-columns: 1fr 1.8fr;
  gap: 8vw;
  align-items: start;
  padding: 72px 0 56px;
  border-bottom: 1px solid rgba(244, 241, 232, 0.18);
}

.footer-brand .brand-logo {
  width: 62px;
  height: 62px;
  padding: 3px;
  background: #f4f1e8;
}

.footer-brand .brand-divider {
  height: 30px;
  background: #f4f1e8;
}

.footer-brand .brand-name {
  font-size: 10px;
}

.footer-tagline {
  margin: 18px 0 0;
  color: var(--lime);
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 48px;
}

.footer-col {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 14px;
}

.footer-col-title {
  margin-bottom: 6px;
  color: var(--lime);
  font-size: 10px;
  letter-spacing: 0.14em;
}

.footer-col a {
  color: #f4f1e8;
  opacity: 0.85;
  transition: opacity 180ms ease, color 180ms ease;
}

.footer-col a:hover {
  opacity: 1;
  color: var(--lime);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  color: rgba(244, 241, 232, 0.6);
}

.back-to-top {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #f4f1e8;
  transition: color 180ms ease;
}

.back-to-top:hover {
  color: var(--lime);
}

.back-to-top-icon {
  width: 14px;
  height: 14px;
}

:focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 5px;
}

@keyframes rotate-blueprint {
  to {
    transform: rotate(360deg);
  }
}

@keyframes robot-enter {
  from {
    opacity: 0;
    transform: translate(70px, 30px) rotate(1deg);
  }
  to {
    opacity: 1;
    transform: translate(0, 0) rotate(0);
  }
}

@keyframes pulse {
  70% {
    box-shadow: 0 0 0 9px rgba(36, 71, 255, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(36, 71, 255, 0);
  }
}

@media (max-width: 1080px) {
  .site-header {
    height: 88px;
  }

  .main-nav {
    gap: 20px;
  }

  .main-nav a:not(.nav-join):not(.nav-ai) {
    display: none;
  }

  .hero {
    min-height: auto;
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto;
    padding-top: 88px;
  }

  .hero-copy {
    width: 80%;
    padding: 56px 0 24px;
  }

  .hero h1 {
    font-size: clamp(56px, 9vw, 96px);
  }

  .hero-visual {
    position: relative;
    width: 100%;
    height: min(420px, 50vh);
    min-height: 280px;
    opacity: 0.88;
  }

  .robot-arm {
    width: min(100%, 560px);
    max-height: 100%;
  }

  .blueprint {
    top: 4%;
    left: 6%;
    width: 160px;
  }

  .blueprint span:nth-child(2) {
    height: 200px;
  }

  .projects-heading,
  .activities-heading {
    grid-template-columns: 1fr;
  }

  .projects-heading > p,
  .activities-heading > p {
    max-width: 660px;
  }

  .project-row {
    grid-template-columns: 56px 1fr 1fr 150px;
  }

  .section-join {
    gap: 5vw;
  }
}

@media (max-width: 900px) {
  .project-row {
    grid-template-columns: 44px 1fr auto;
    grid-template-areas:
      "index title meta"
      "index summary meta";
    row-gap: 12px;
    column-gap: 22px;
    align-items: start;
    min-height: 0;
    padding: 28px 0;
  }

  .project-index {
    grid-area: index;
  }

  .project-title-wrap {
    grid-area: title;
  }

  .project-summary {
    grid-area: summary;
  }

  .project-meta {
    grid-area: meta;
    flex-direction: column;
    align-items: flex-end;
    gap: 10px;
  }

  .project-row:hover {
    padding: 28px 14px;
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 48px;
  }
}

@media (max-width: 760px) {
  .site-header {
    position: absolute;
    padding: 0 20px;
  }

  .brand {
    gap: 10px;
  }

  .brand-name,
  .site-header .brand-divider {
    display: none;
  }

  .site-header .brand-logo {
    width: 58px;
    height: 58px;
  }

  .main-nav .nav-join {
    padding: 10px 12px;
    font-size: 13px;
  }

  .main-nav {
    gap: 12px;
  }

  .main-nav .nav-ai {
    padding: 10px 0;
    font-size: 13px;
  }

  .hero {
    min-height: auto;
    padding-right: 20px;
    padding-left: 20px;
    background-size: 72px 72px;
  }

  .hero-copy {
    width: 100%;
    justify-content: flex-start;
    padding: 48px 0 16px;
  }

  .eyebrow {
    margin-bottom: 20px;
  }

  .hero h1 {
    font-size: clamp(44px, 13vw, 72px);
    line-height: 1;
  }

  .hero-intro {
    max-width: 88%;
    margin-top: 22px;
    font-size: 15px;
    line-height: 1.7;
  }

  .hero-actions {
    width: 100%;
    gap: 12px;
    margin-top: 28px;
  }

  .button {
    min-width: 0;
    height: 52px;
    flex: 1;
    padding: 0 16px;
    font-size: 15px;
  }

  .button-icon {
    width: 18px;
    height: 18px;
  }

  .hero-visual {
    height: min(320px, 42vh);
    min-height: 240px;
    opacity: 0.78;
  }

  .robot-arm {
    width: min(100%, 420px);
  }

  .blueprint {
    top: 0;
    left: 8%;
    width: 130px;
  }

  .blueprint span:nth-child(2) {
    height: 160px;
  }

  .hero-proof {
    min-height: 54px;
    grid-template-columns: repeat(3, 1fr);
    font-size: 9px;
    text-align: center;
  }

  .hero-proof span {
    padding: 0 6px;
  }

  .section {
    padding: 80px 20px;
  }

  .section-kicker {
    grid-template-columns: 62px 1fr;
    margin-bottom: 54px;
  }

  .section-kicker span:first-child::after {
    width: 18px;
  }

  .about-grid,
  .section-join {
    grid-template-columns: 1fr;
  }

  .about-grid {
    gap: 64px;
  }

  .about-grid > h2,
  .projects-heading h2,
  .activities-heading h2,
  .section-join h2 {
    font-size: clamp(44px, 14vw, 68px);
  }

  .about-lead {
    margin-bottom: 48px;
    font-size: 18px;
  }

  .principles article {
    grid-template-columns: 72px 1fr;
    gap: 12px;
  }

  .principles p {
    grid-column: 2;
  }

  .projects-heading,
  .activities-heading {
    gap: 32px;
    margin-bottom: 64px;
  }

  .project-row {
    grid-template-columns: 40px 1fr auto;
    row-gap: 8px;
    column-gap: 12px;
    padding: 24px 0;
  }

  .project-row:hover {
    padding: 24px 8px;
  }

  .project-summary {
    font-size: 14px;
  }

  .project-tags {
    gap: 6px;
  }

  .project-tags span + span::before {
    margin-right: 6px;
  }

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

  .activity-grid article,
  .activity-grid article:first-child {
    min-height: 280px;
    padding: 30px 0;
    border-right: 0;
    border-bottom: 1px solid rgba(244, 241, 232, 0.28);
  }

  .activity-grid h3 {
    margin-top: 54px;
  }

  .activity-line,
  .activity-grid article:first-child .activity-line {
    right: 0;
    bottom: 30px;
    left: 0;
  }

  .section-join {
    gap: 70px;
  }

  .wechat-card {
    width: 100%;
    justify-self: stretch;
    box-shadow: 8px 8px 0 var(--blue);
  }

  .join-intro {
    font-size: 17px;
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 40px;
    padding-top: 48px;
    padding-bottom: 40px;
  }

  .footer-cols {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-bottom {
    align-items: flex-start;
    flex-direction: column;
    gap: 16px;
    padding-top: 24px;
    padding-bottom: 32px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}


.page {
  height: 100dvh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background-color: var(--paper);
  background-image: linear-gradient(rgba(36, 71, 255, 0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 71, 255, 0.08) 1px, transparent 1px);
  background-size: 96px 96px;
}

.header {
  display: flex;
  min-height: 92px;
  align-items: center;
  justify-content: space-between;
  padding: 12px clamp(20px, 4.5vw, 72px);
  border-bottom: 1px solid var(--ink-30);
  background: var(--paper-soft);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 13px;
  color: var(--ink);
  font-family: var(--font-geist-mono), monospace;
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.08em;
}

.brand img {
  width: 58px;
  height: 58px;
  object-fit: contain;
}

.brand span {
  display: grid;
  gap: 4px;
}

.brand small {
  color: var(--muted);
  font-size: 9px;
  font-weight: 650;
  letter-spacing: 0.04em;
}

.backLink,
.newChatButton,
.sendButton {
  border: 1px solid var(--ink);
  font: inherit;
  font-weight: 800;
}

.backLink {
  padding: 12px 16px;
  font-size: 14px;
}

.backLink:hover,
.backLink:focus-visible {
  background: var(--lime);
  color: var(--on-lime);
}

.chatShell {
  display: grid;
  flex: 1 1 auto;
  min-height: 0;
  width: min(1440px, calc(100% - clamp(32px, 7vw, 128px)));
  margin: clamp(12px, 1.5vw, 20px) auto;
  grid-template-columns: minmax(260px, 0.36fr) minmax(0, 1fr);
  border: 1px solid var(--ink);
  background: var(--paper);
  box-shadow: 14px 14px 0 var(--blue);
}

.sidebar {
  display: flex;
  min-height: 100%;
  flex-direction: column;
  gap: 20px;
  padding: clamp(20px, 2.5vw, 40px);
  border-right: 1px solid var(--ink);
  background: var(--lime);
  width: 268px;
  flex-shrink: 0;
  overflow: hidden;
}

.sectionCode,
.panelHeader,
.messageLabel,
.composerLabel,
.composerHint,
.statusCard span,
.typing {
  font-family: var(--font-geist-mono), monospace;
  letter-spacing: 0.08em;
}

.sectionCode {
  margin: 0 0 30px;
  color: var(--on-lime-accent);
  font-size: 11px;
  font-weight: 800;
}

.sidebar h1 {
  margin: 0;
  color: var(--on-lime);
  font-size: clamp(52px, 5.5vw, 88px);
  font-weight: 900;
  letter-spacing: -0.08em;
  line-height: 0.9;
}

.description {
  max-width: 320px;
  margin: 28px 0 0;
  color: var(--on-lime);
  opacity: 0.86;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.7;
}

.statusCard {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px;
  border: 1px solid var(--ink);
  background: var(--paper-soft);
}

.statusDot {
  width: 10px;
  height: 10px;
  margin-top: 5px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--blue);
}

.statusChecking {
  animation: statusPulse 900ms ease-in-out infinite alternate;
}

.statusOnline {
  background: #3f9d31;
}

.statusOffline {
  background: var(--muted);
}

.statusCard div {
  display: grid;
  gap: 5px;
}

.statusCard strong {
  font-size: 13px;
}

.statusCard span:not(.statusDot) {
  color: var(--muted);
  font-size: 10px;
  font-weight: 700;
}

.newChatButton {
  display: flex;
  min-height: 52px;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: #11110f;
  color: #f4f1e8;
  cursor: pointer;
}

.newChatButton span {
  color: var(--lime);
  font-size: 22px;
}

.newChatButton:hover,
.newChatButton:focus-visible {
  background: var(--blue);
}

.sidebarHeader {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.sidebarClose {
  display: none;
  width: 32px;
  height: 32px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--ink);
  background: transparent;
  color: var(--on-lime);
  font-size: 16px;
  cursor: pointer;
}

.headerRight {
  display: flex;
  align-items: center;
  gap: 12px;
}

.sidebarToggle {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--ink);
  background: transparent;
  color: var(--ink);
  font-size: 18px;
  cursor: pointer;
}

.historyLabel {
  color: var(--on-lime);
  opacity: 0.6;
  font-family: var(--font-geist-mono), monospace;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.1em;
  padding: 4px 4px 2px;
}

.historyList {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
  gap: 2px;
  overflow-y: auto;
  min-height: 0;
  padding-bottom: 8px;
}

.historyEmpty {
  color: var(--on-lime);
  opacity: 0.5;
  font-size: 12px;
  padding: 8px 4px;
}

.historyItem {
  display: flex;
  align-items: stretch;
  gap: 0;
  transition: background 150ms ease;
}

.historyItem:hover {
  background: rgba(17, 17, 15, 0.08);
}

.historyItemActive {
  background: rgba(17, 17, 15, 0.14);
}

.historyItemMain {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
  padding: 9px 8px;
  border: 0;
  background: transparent;
  text-align: left;
  cursor: pointer;
  font: inherit;
}

.historyItemTitle {
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--on-lime);
  font-size: 13px;
  font-weight: 700;
}

.historyItemTime {
  color: var(--on-lime);
  opacity: 0.5;
  font-size: 10px;
  font-weight: 500;
}

.historyItemDelete {
  display: none;
  flex: 0 0 auto;
  padding: 9px 10px;
  border: 0;
  background: transparent;
  color: var(--on-lime);
  opacity: 0.5;
  font-size: 16px;
  cursor: pointer;
}

.historyItem:hover .historyItemDelete {
  display: block;
}

.historyItemDelete:hover {
  opacity: 1;
}

.backdrop {
  display: none;
}

.modalBackdrop {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(17, 17, 15, 0.5);
}

.modal {
  width: min(360px, calc(100% - 48px));
  padding: 28px 24px 20px;
  border: 1px solid var(--ink);
  background: var(--paper);
  box-shadow: 8px 8px 0 var(--blue);
}

.modalTitle {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 800;
}

.modalDesc {
  margin: 0 0 24px;
  color: var(--ink-60);
  font-size: 14px;
  line-height: 1.6;
}

.modalActions {
  display: flex;
  justify-content: flex-end;
  gap: 12px;
}

.modalCancel {
  padding: 10px 16px;
  border: 1px solid var(--ink);
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

.modalConfirm {
  padding: 10px 16px;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

.modalConfirm:hover {
  background: var(--blue);
  color: var(--paper);
}

.chatPanel {
  position: relative;
  display: grid;
  min-width: 0;
  min-height: 0;
  grid-template-rows: auto minmax(0, 1fr) auto;
}

.panelHeader {
  display: flex;
  min-height: 64px;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 0 clamp(20px, 3vw, 40px);
  border-bottom: 1px solid var(--ink);
  color: var(--muted);
  font-size: 10px;
  font-weight: 750;
}

.messages {
  min-height: 0;
  overflow-y: auto;
  padding: clamp(22px, 3vw, 44px);
}

.emptyState {
  display: grid;
  min-height: 100%;
  max-width: 620px;
  align-content: center;
  justify-items: start;
  margin: auto;
}

.emptyMark {
  padding: 8px 10px;
  border: 1px solid var(--blue);
  color: var(--blue);
  font-family: var(--font-geist-mono), monospace;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.1em;
}

.emptyState h2 {
  margin: 26px 0 0;
  font-size: clamp(36px, 4.5vw, 66px);
  font-weight: 900;
  letter-spacing: -0.07em;
  line-height: 0.98;
}

.emptyState p {
  max-width: 520px;
  margin: 22px 0 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.8;
}

.messageRow {
  display: grid;
  gap: 9px;
  margin-bottom: 28px;
}

.assistantMessageRow {
  justify-items: start;
}

.userMessageRow {
  justify-items: end;
}

.messageLabel {
  color: var(--blue);
  font-size: 10px;
  font-weight: 800;
}

.thinkingLine {
  color: var(--muted);
  font-family: var(--font-geist-mono), monospace;
  font-size: 10px;
  font-weight: 750;
  letter-spacing: 0.07em;
}

.messageBubble {
  max-width: min(560px, 86%);
  margin: 0;
  padding: 16px 18px;
  border: 1px solid var(--ink);
  background: var(--white);
  font-size: 16px;
  font-weight: 550;
  line-height: 1.7;
  white-space: pre-wrap;
}

.userBubble {
  background: var(--lime);
  color: var(--on-lime);
}

.typing {
  display: flex;
  align-items: center;
  gap: 7px;
  margin-top: 4px;
  color: var(--muted);
  font-size: 10px;
  font-weight: 800;
}

.typing i {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--blue);
  animation: typingPulse 800ms ease-in-out infinite alternate;
}

.typing i:nth-of-type(2) {
  animation-delay: 120ms;
}

.typing i:nth-of-type(3) {
  animation-delay: 240ms;
}

.streamNotice {
  margin: 8px 0 0;
  color: var(--muted);
  font-family: var(--font-geist-mono), monospace;
  font-size: 11px;
  line-height: 1.6;
}

.composer {
  padding: 16px clamp(20px, 3vw, 40px) 18px;
  border-top: 1px solid var(--ink);
  background: var(--paper);
}

.composerLabel,
.composerHint {
  display: block;
  color: var(--muted);
  font-size: 9px;
  font-weight: 750;
}

.composerControls {
  display: flex;
  align-items: stretch;
  gap: 10px;
  margin-top: 9px;
}

.composerToolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.thinkingToggle {
  display: inline-flex;
  height: 32px;
  align-items: center;
  gap: 7px;
  padding: 0 11px;
  border: 1px solid var(--ink);
  border-radius: 6px;
  background: rgba(244, 241, 232, 0.56);
  color: var(--muted);
  cursor: pointer;
  font-family: var(--font-geist-mono), monospace;
  font-size: 12px;
  font-weight: 750;
  letter-spacing: 0.06em;
}

.thinkingToggleActive {
  border-color: var(--blue);
  background: rgba(36, 71, 255, 0.1);
  color: var(--blue);
}

.thinkingToggle span {
  color: var(--blue);
  font-size: 14px;
  line-height: 1;
}

.thinkingToggle:disabled {
  cursor: not-allowed;
  opacity: 0.6;
}

.composerInput {
  min-width: 0;
  min-height: 54px;
  flex: 1;
  resize: vertical;
  padding: 15px 16px;
  border: 1px solid var(--ink);
  border-radius: 0;
  background: var(--white);
  color: var(--ink);
  font: inherit;
  line-height: 1.4;
}

.composerInput::placeholder {
  color: var(--muted);
}

.sendButton {
  min-width: 112px;
  padding: 0 16px;
  background: var(--lime);
  color: var(--on-lime);
  cursor: pointer;
}

.sendButton:hover:not(:disabled),
.sendButton:focus-visible:not(:disabled) {
  background: var(--blue);
  color: var(--paper);
}

.sendButton:disabled,
.composerInput:disabled {
  cursor: not-allowed;
  opacity: 0.56;
}

.composerHint {
  margin: 8px 0 0;
}

.messages,
.historyList {
  scrollbar-width: thin;
  scrollbar-color: rgba(17, 17, 15, 0.2) transparent;
}

.messages::-webkit-scrollbar,
.historyList::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

.messages::-webkit-scrollbar-track,
.historyList::-webkit-scrollbar-track {
  background: transparent;
}

.messages::-webkit-scrollbar-thumb,
.historyList::-webkit-scrollbar-thumb {
  background: rgba(17, 17, 15, 0.18);
  border-radius: 3px;
}

.messages::-webkit-scrollbar-thumb:hover,
.historyList::-webkit-scrollbar-thumb:hover {
  background: rgba(17, 17, 15, 0.32);
}

.scrollToBottom {
  position: absolute;
  bottom: 14px;
  right: 18px;
  z-index: 10;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 7px 12px;
  border: 1px solid var(--ink);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-geist-mono), monospace;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  cursor: pointer;
  box-shadow: 4px 4px 0 var(--blue);
}

.scrollToBottom:hover {
  background: var(--lime);
}

@keyframes typingPulse {
  to {
    opacity: 0.3;
    transform: translateY(-2px);
  }
}

@keyframes statusPulse {
  to {
    opacity: 0.35;
    transform: scale(0.75);
  }
}

@media (max-width: 900px) {
  .chatShell {
    width: min(100% - 40px, 760px);
    grid-template-columns: 1fr;
    box-shadow: 9px 9px 0 var(--blue);
  }

  .sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 30;
    width: min(280px, 80vw);
    transform: translateX(-100%);
    transition: transform 220ms ease;
    border-right: 1px solid var(--ink);
    border-bottom: 0;
  }

  .sidebarOpen,
  .chatShellShifted .sidebar {
    transform: translateX(0);
  }

  .sidebarClose {
    display: flex;
  }

  .sidebarToggle {
    display: flex;
  }

  .backdrop {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 20;
    background: rgba(17, 17, 15, 0.4);
    opacity: 0;
    pointer-events: none;
    transition: opacity 220ms ease;
  }

  .backdropVisible,
  .chatShellShifted .backdrop {
    opacity: 1;
    pointer-events: auto;
  }
}

@media (max-width: 620px) {
  .header {
    min-height: 76px;
    padding: 8px 16px;
  }

  .brand img {
    width: 46px;
    height: 46px;
  }

  .brand {
    font-size: 14px;
  }

  .brand small {
    display: none;
  }

  .backLink {
    padding: 9px 10px;
    font-size: 12px;
  }

  .chatShell {
    width: 100%;
    margin: 0;
    border-right: 0;
    border-left: 0;
    box-shadow: none;
  }

  .sidebar {
    width: min(260px, 82vw);
  }

  .statusCard {
    min-width: 0;
    padding: 10px;
  }

  .statusCard strong {
    font-size: 11px;
  }

  .statusCard span:not(.statusDot) {
    font-size: 8px;
  }

  .newChatButton {
    min-width: 104px;
    font-size: 13px;
  }

  .panelHeader {
    min-height: 46px;
    padding: 0 16px;
    font-size: 8px;
  }

  .messages {
    padding: 24px 16px;
  }

  .emptyState h2 {
    font-size: 42px;
  }

  .emptyState p,
  .messageBubble {
    font-size: 15px;
  }

  .composer {
    padding: 14px 16px calc(14px + env(safe-area-inset-bottom));
  }

  .composerControls {
    gap: 8px;
  }

  .composerInput {
    min-height: 50px;
    padding: 14px 12px;
  }

  .sendButton {
    min-width: 76px;
    padding: 0 10px;
  }

  .composerHint {
    display: none;
  }
}