/* ==========================================================================
   VueIC · 篇章层（首页六个篇章的版式与视觉）
   ========================================================================== */

/* ============================== 篇章一 · Hero ============================== */
.hero {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 100vh;
  min-height: 100svh;
  padding-top: calc(var(--header-h) + 40px);
  padding-bottom: 120px;
  overflow: hidden;
  isolation: isolate;
}

.hero__canvas {
  position: absolute;
  inset: 0;
  z-index: -3;
}
.hero__canvas canvas {
  position: absolute;
  inset: 0;
  width: 100% !important;
  height: 100% !important;
}

/* WebGL 不可用时的降级：CSS 渐变背景 + 静态微光（方案 7.2） */
.hero__fallback {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(720px 460px at 20% 26%, rgba(59, 125, 216, 0.14) 0%, rgba(8, 9, 13, 0) 70%),
    radial-gradient(600px 420px at 80% 68%, rgba(212, 165, 116, 0.12) 0%, rgba(8, 9, 13, 0) 72%),
    linear-gradient(180deg, #0A0C12 0%, var(--bg) 70%);
}

.hero__vignette {
  position: absolute;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(124% 84% at 50% 42%, rgba(8, 9, 13, 0) 42%, rgba(8, 9, 13, 0.58) 100%),
    linear-gradient(180deg, rgba(8, 9, 13, 0.42) 0%, rgba(8, 9, 13, 0) 28%, rgba(8, 9, 13, 0.8) 100%);
  pointer-events: none;
}

.hero__grid {
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(90deg, var(--text-04) 1px, transparent 1px),
    linear-gradient(180deg, var(--text-04) 1px, transparent 1px);
  background-size: 96px 96px;
  mask-image: radial-gradient(70% 60% at 50% 45%, #000 0%, transparent 78%);
  -webkit-mask-image: radial-gradient(70% 60% at 50% 45%, #000 0%, transparent 78%);
  pointer-events: none;
}

.hero__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}
.hero__title {
  font-family: var(--font-heading);
  font-size: clamp(48px, 2rem + 6vw, 64px);
  font-weight: 400;
  line-height: 1.05;
  letter-spacing: 0.01em;
}
.hero__subtitle {
  margin-top: var(--space-2);
  font-family: var(--font-body);
  font-size: 20px;
  font-weight: 300;
  letter-spacing: 0.06em;
  color: var(--text-2);
}
.hero__desc {
  margin-top: var(--space-4);
  max-width: 600px;
  font-size: 16px;
  line-height: 1.95;
  color: var(--text-2);
}
.hero__cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-5);
}

.hero__scroll {
  position: absolute;
  left: 50%;
  bottom: 40px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  transform: translateX(-50%);
}
.hero__scroll-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.28em;
  color: var(--text-3);
}
.hero__scroll-line {
  position: relative;
  display: block;
  width: 1px;
  height: 48px;
  background: var(--border);
  overflow: hidden;
}
.hero__scroll-line::after {
  content: "";
  position: absolute;
  inset: 0 auto auto 0;
  width: 1px;
  height: 40%;
  background: var(--brand);
  animation: scroll-cue 2.4s var(--ease-in-out) infinite;
}

/* ============================== 篇章二 · About ============================== */
.section--about { padding-top: calc(var(--section-y) + 24px); }

.about__copy {
  max-width: var(--container-text);
  display: grid;
  gap: var(--space-3);
}
.about__copy p {
  font-size: 16px;
  line-height: 1.9;
  color: var(--text);
}
.about__divider {
  width: 100%;
  max-width: var(--container-text);
  height: 1px;
  margin: var(--space-8) 0;
  background: linear-gradient(90deg, var(--border) 0%, rgba(30, 35, 48, 0.05) 100%);
}

.research-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-3);
}
.research-card {
  position: relative;
  padding: var(--card-pad);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(22, 26, 36, 0.5) 0%, rgba(15, 17, 24, 0.35) 100%);
  transition: border-color var(--dur-card) var(--ease-out),
              transform var(--dur-card) var(--ease-out),
              background-color var(--dur-card) var(--ease-out);
}
.research-card:hover {
  border-color: var(--brand-40);
  transform: translateY(-3px);
}
.research-card__icon { display: block; margin-bottom: var(--space-3); }
.research-card__title {
  margin-bottom: 10px;
  font-family: var(--font-heading);
  font-size: 21px;
}
.research-card__desc {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-2);
}

/* ============================== 篇章三 · Projects ========================== */
.section--projects .section__title { margin-bottom: var(--block-y); }

.featured-card {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  align-items: center;
  gap: var(--space-6);
  padding: clamp(28px, 3.4vw, 44px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(520px 320px at var(--mx, 82%) var(--my, 12%), var(--brand-08) 0%, rgba(8, 9, 13, 0) 62%),
    linear-gradient(180deg, rgba(22, 26, 36, 0.72) 0%, rgba(15, 17, 24, 0.82) 100%);
  overflow: hidden;
  transition: border-color var(--dur-card) var(--ease-out),
              box-shadow var(--dur-card) var(--ease-out),
              transform var(--dur-card) var(--ease-out);
}
.featured-card__rule {
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--brand) 0%, var(--brand-deep) 100%);
  transition: width var(--dur-card) var(--ease-out);
}
.featured-card:hover {
  border-color: var(--brand);
  box-shadow: var(--shadow-card);
  transform: translateY(-2px);
}
.featured-card:hover .featured-card__rule { width: 3px; }

.featured-card__tag {
  margin-bottom: var(--space-3);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--warm);
}
.featured-card__title {
  margin-bottom: 14px;
  font-family: var(--font-heading);
  font-size: clamp(26px, 1.4rem + 1.4vw, 32px);
  line-height: 1.25;
}
.featured-card__title-en {
  display: inline-block;
  margin-left: 6px;
  font-style: italic;
  color: var(--text-2);
}
.featured-card__desc {
  margin-bottom: var(--space-3);
  max-width: 520px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-2);
}
.featured-card__body .tag-list { margin-bottom: var(--space-5); }
.featured-card:hover .tag-list li { border-color: var(--border); color: var(--text); }

.featured-card__visual {
  color: var(--brand);
  opacity: 0.9;
}
.featured-card__visual svg { width: 100%; height: auto; }
.fcv-nodes circle {
  fill: rgba(59, 125, 216, 0.12);
  stroke: var(--brand);
  stroke-width: 1.1;
}
.fcv-nodes .fcv-core {
  fill: var(--brand);
  stroke: none;
  filter: drop-shadow(0 0 12px rgba(59, 125, 216, 0.65));
  transform-origin: 160px 130px;
  animation: core-pulse 4.4s var(--ease-in-out) infinite;
}
.featured-card__visual svg { animation: slow-spin 90s linear infinite; }

/* 区块二：社会痛点 */
.project-detail { margin-top: clamp(72px, 9vw, 120px); }
.section--projects .section__subtitle { margin-top: var(--space-2); }
.pain-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-3);
  margin-top: var(--block-y);
}
.pain-card {
  padding: var(--card-pad);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: rgba(15, 17, 24, 0.6);
  transition: border-color var(--dur-card) var(--ease-out), transform var(--dur-card) var(--ease-out);
}
.pain-card:hover { border-color: var(--brand-40); transform: translateY(-3px); }
.pain-card__icon { display: block; margin-bottom: var(--space-3); }
.pain-card__title {
  margin-bottom: 10px;
  font-family: var(--font-heading);
  font-size: 19px;
}
.pain-card__desc {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-2);
}

/* 区块二：解决方案（暖色强调，与痛点的冷色形成对照） */
.solution {
  position: relative;
  margin-top: clamp(72px, 9vw, 120px);
  padding: clamp(28px, 3.4vw, 48px);
  border: 1px solid var(--warm-16);
  border-radius: var(--radius-lg);
  background:
    radial-gradient(680px 320px at 12% 0%, var(--warm-08) 0%, rgba(8, 9, 13, 0) 60%),
    linear-gradient(180deg, rgba(22, 26, 36, 0.6) 0%, rgba(15, 17, 24, 0.5) 100%);
}
.solution__title { color: var(--text); }
.solution__title::after {
  content: "";
  display: block;
  width: 48px;
  height: 1px;
  margin-top: 18px;
  background: var(--warm);
}

.flow {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-5);
  margin-top: var(--space-6);
}
.flow__step {
  position: relative;
  padding-top: var(--space-3);
  border-top: 1px solid var(--warm-16);
}
/* 步骤之间的连接线 */
.flow__step + .flow__step::before {
  content: "";
  position: absolute;
  left: calc(-1 * var(--space-5));
  top: -1px;
  width: var(--space-5);
  height: 1px;
  background: linear-gradient(90deg, var(--warm-32) 0%, rgba(212, 165, 116, 0) 100%);
}
.flow__step + .flow__step::after {
  content: "";
  position: absolute;
  left: calc(-1 * var(--space-5) - 1px);
  top: -3.5px;
  width: 6px; height: 6px;
  border-top: 1px solid var(--warm-32);
  border-right: 1px solid var(--warm-32);
  transform: rotate(45deg) translateY(3.6px);
}
.flow__index {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--warm);
}
.flow__title {
  margin-bottom: 10px;
  font-family: var(--font-heading);
  font-size: 20px;
}
.flow__desc {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-2);
}
.solution__value {
  max-width: 640px;
  margin-top: var(--block-y);
  padding-left: var(--space-3);
  border-left: 2px solid var(--warm);
  font-family: var(--font-heading);
  font-size: clamp(18px, 1rem + 0.7vw, 22px);
  line-height: 1.7;
  color: var(--text);
}

/* ============================== 篇章四 · Lab ============================== */
.section--lab { padding-block: 0; padding-inline: 0; }
.lab-banner {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 60vh;
  padding: clamp(64px, 9vw, 96px) var(--pad-x);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  background: var(--bg-2);
  overflow: hidden;
}
.lab-banner__glow {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(520px 320px at 14% 34%, rgba(59, 125, 216, 0.16) 0%, rgba(15, 17, 24, 0) 70%),
    radial-gradient(460px 300px at 86% 62%, rgba(212, 165, 116, 0.10) 0%, rgba(15, 17, 24, 0) 72%);
  pointer-events: none;
}
/* 微弱的粒子（密度远低于 Hero）：两层错位的点阵缓慢漂移 */
.lab-banner__dust {
  position: absolute;
  inset: -8% -4%;
  background-image:
    radial-gradient(rgba(90, 154, 240, 0.55) 1px, transparent 1.4px),
    radial-gradient(rgba(212, 165, 116, 0.5) 1px, transparent 1.4px);
  background-size: 139px 113px, 197px 167px;
  background-position: 0 0, 53px 67px;
  opacity: 0.16;
  animation: dust-drift 90s linear infinite;
  mask-image: radial-gradient(82% 74% at 50% 50%, #000 0%, transparent 86%);
  -webkit-mask-image: radial-gradient(82% 74% at 50% 50%, #000 0%, transparent 86%);
  pointer-events: none;
}
.lab-banner__inner {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}
.lab-banner__icon {
  display: block;
  margin-bottom: var(--space-4);
  color: var(--brand);
}
.lab-banner__icon svg { width: 48px; height: 48px; }
.lab-banner__title {
  font-family: var(--font-heading);
  font-size: clamp(28px, 1.5rem + 1.6vw, 36px);
  line-height: 1.2;
}
.lab-banner__subtitle {
  margin-top: 10px;
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 300;
  letter-spacing: 0.04em;
  color: var(--text-2);
}
.lab-banner__desc {
  margin-top: var(--space-3);
  max-width: 560px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-2);
}
.lab-banner .btn-lab { margin-top: var(--space-5); }
.lab-banner__hint {
  margin-top: var(--space-2);
  font-size: 13px;
  color: var(--text-2);
}

/* ============================== 篇章五 · Contact ========================== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(272px, 1fr));
  align-items: stretch;
  gap: var(--space-3);
  margin-top: var(--block-y);
}
.contact-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: var(--card-pad);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(22, 26, 36, 0.5) 0%, rgba(15, 17, 24, 0.4) 100%);
  transition: border-color var(--dur-card) var(--ease-out),
              transform var(--dur-card) var(--ease-out),
              background-color var(--dur-card) var(--ease-out);
}
.contact-card:not(.contact-card--skeleton):hover {
  border-color: var(--brand-40);
  transform: translateY(-2px);
}
.contact-card__icon {
  display: grid;
  place-items: center;
  width: 34px; height: 34px;
  margin-bottom: 6px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--brand);
}
.contact-card__icon svg { width: 18px; height: 18px; }
.contact-card__label {
  font-size: 14px;
  color: var(--text-2);
}
.contact-card__value {
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  word-break: break-word;
}
a.contact-card__value { transition: color var(--dur-hover) var(--ease-out); }
a.contact-card__value:hover { color: var(--brand-bright); }
.contact-card__qr {
  width: 120px;
  height: 120px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  object-fit: contain;
}
.contact-card__copy {
  align-self: flex-start;
  margin-top: 6px;
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  font-size: 12px;
  font-family: var(--font-mono);
  color: var(--text-2);
  transition: border-color var(--dur-hover) var(--ease-out), color var(--dur-hover) var(--ease-out);
}
.contact-card__copy:hover { border-color: var(--brand-40); color: var(--text); }

.contact-card--skeleton { gap: 14px; }
.contact-empty {
  margin-top: var(--block-y);
  font-family: var(--font-heading);
  font-size: 20px;
  color: var(--text-2);
  animation: breathe 2s var(--ease-in-out) infinite;
}

/* ============================== 篇章六 · Footer =========================== */
.site-footer {
  padding-block: clamp(64px, 8vw, 96px) 40px;
  border-top: 1px solid var(--border);
  background: linear-gradient(180deg, var(--bg-2) 0%, var(--bg) 100%);
}
.site-footer__top {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: var(--space-6);
}
.site-footer__brand-name {
  display: block;
  font-family: var(--font-heading);
  font-size: 26px;
  letter-spacing: 0.02em;
}
.site-footer__brand-sub {
  margin-top: 8px;
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--text-2);
}
.site-footer__brand-note {
  margin-top: var(--space-2);
  max-width: 360px;
  font-size: 14px;
  line-height: 1.85;
  color: var(--text-2);
}
.site-footer__col-title {
  margin-bottom: var(--space-2);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-2);
}
.site-footer__col ul { display: grid; gap: 10px; }
.site-footer__col a {
  font-size: 15px;
  color: var(--text-2);
}
.site-footer__col a:hover { color: var(--text); }
.site-footer__col a[target="_blank"]::after { content: ""; }
.site-footer__pending { color: var(--text-3); }

.site-footer__divider {
  height: 1px;
  margin: var(--space-8) 0 var(--space-4);
  background: linear-gradient(90deg, var(--border) 0%, rgba(30, 35, 48, 0.08) 100%);
}
.site-footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  flex-wrap: wrap;
  font-size: 13px;
  /* 方案 2.1 将「版权信息」归入文字弱化色；此处为保证 ≥4.5:1 的可读性
     使用文字次级色 --text-2，弱化色仅用于纯装饰元素。 */
  color: var(--text-2);
}
.site-footer__icp a {
  color: var(--text-2);
  border-bottom: 1px solid transparent;
  transition: color var(--dur-hover) var(--ease-out), border-color var(--dur-hover) var(--ease-out);
}
.site-footer__icp a:hover { color: var(--brand-bright); border-bottom-color: var(--brand); }

/* ============================== 响应式断点 ================================
   方案 7.3：≥1280 完整布局；1024–1279 边距与字号微调；
   768–1023 两栏变单栏、粒子数量降低；<768 移动端布局
   ======================================================================== */
@media (max-width: 1279px) {
  .featured-card { grid-template-columns: minmax(0, 1fr) 240px; }
  .brand__sub { display: none; }
}

@media (max-width: 1023px) {
  .site-nav, .site-header__cta { display: none; }
  .nav-toggle { display: grid; }
  .featured-card { grid-template-columns: minmax(0, 1fr); }
  .featured-card__visual { display: none; }
  .research-grid, .pain-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .flow { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .tech__grid { grid-template-columns: minmax(0, 1fr); }
  .site-footer__top { grid-template-columns: 1fr 1fr; gap: var(--space-5); }
}

@media (max-width: 767px) {
  body { font-size: 15.5px; }
  .hero { padding-bottom: 96px; }
  .hero__desc br { display: none; }
  .hero__cta { width: 100%; flex-direction: column; }
  .hero__cta .btn { width: 100%; }
  .research-grid, .pain-grid, .flow { grid-template-columns: minmax(0, 1fr); }
  .flow { gap: var(--space-4); }
  .flow__step + .flow__step::before {
    left: 0; top: calc(-1 * var(--space-4));
    width: 24px;
    background: linear-gradient(90deg, var(--warm-32) 0%, rgba(212, 165, 116, 0) 100%);
  }
  .flow__step + .flow__step::after { left: 22px; top: calc(-1 * var(--space-4) - 2.5px); }
  .site-footer__top { grid-template-columns: minmax(0, 1fr); }
  .site-footer__bottom { flex-direction: column; align-items: flex-start; }
  .lab-banner { min-height: auto; }
  .btn-lab { width: 100%; }
  .tech__toggle-hint { display: none; }
  .contact-grid { grid-template-columns: minmax(0, 1fr); }
}