:root {
  --bg: #03070f;
  --bg-2: #07111f;
  --panel: rgba(12, 22, 41, 0.78);
  --line: rgba(128, 180, 254, 0.2);
  --line-strong: rgba(22, 100, 255, 0.72);
  --text: #f7fbff;
  --soft: #c7d4ea;
  --muted: #8e9bb1;
  --blue: #1664ff;
  --cyan: #15dccd;
  --violet: #6c4cff;
  --shadow: 0 42px 120px rgba(0, 0, 0, 0.52);
  --title-font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Arial Black", sans-serif;
  --page-gutter: clamp(56px, 6.8vw, 112px);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  overflow-x: hidden;
  color: var(--text);
  background:
    radial-gradient(ellipse at 78% 0%, rgba(22, 100, 255, 0.26), transparent 34rem),
    radial-gradient(ellipse at 5% 8%, rgba(108, 76, 255, 0.18), transparent 30rem),
    radial-gradient(ellipse at 88% 58%, rgba(21, 220, 205, 0.08), transparent 36rem),
    linear-gradient(180deg, #02050b 0%, #07101d 48%, #02050b 100%);
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

body::before,
body::after {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
}

body::before {
  z-index: -2;
  opacity: 0.22;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: linear-gradient(180deg, #000, transparent 78%);
}

body::after {
  z-index: -1;
  opacity: 0.18;
  background-image: radial-gradient(rgba(255, 255, 255, 0.95) 0.7px, transparent 0.7px);
  background-size: 6px 6px;
  mask-image: radial-gradient(ellipse at 40% 0%, #000 0%, transparent 44%);
}

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

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

.progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 80;
  width: 0%;
  height: 2px;
  background: linear-gradient(90deg, var(--blue), var(--cyan));
  box-shadow: 0 0 18px rgba(21, 220, 205, 0.75);
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 70;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 18px var(--page-gutter);
  background: rgba(3, 7, 15, 0.72);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  font-weight: 800;
  white-space: nowrap;
}

.brand img {
  width: 30px;
  height: 30px;
}

.tiktok-brand img {
  width: 132px;
  height: auto;
}

.page-nav {
  display: flex;
  gap: 4px;
}

.page-nav a {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 36px;
  padding: 0 13px;
  border-radius: 8px;
  color: var(--muted);
  font-size: 13px;
  transition: color 0.2s ease, background 0.2s ease;
}

.page-nav a span {
  color: rgba(142, 155, 177, 0.68);
  font-size: 11px;
  font-variant-numeric: tabular-nums;
}

.page-nav a:hover,
.page-nav a.active {
  color: #fff;
  background: rgba(22, 100, 255, 0.16);
}

main {
  position: relative;
  z-index: 1;
  counter-reset: case-section;
}

.hero,
.section {
  width: min(1360px, calc(100vw - (var(--page-gutter) * 2)));
  margin: 0 auto;
}

.hero {
  position: relative;
  min-height: 100vh;
  padding: 128px 0 80px;
}

.hero > *:not(.hero-mark) {
  position: relative;
  z-index: 1;
}

.hero-mark {
  position: absolute;
  top: 126px;
  right: -9vw;
  width: 48vw;
  max-width: 640px;
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  z-index: 0;
  opacity: 0.2;
  transform: translate3d(var(--mark-x, 0), var(--mark-y, 0), 0);
  transition: opacity 0.28s ease, transform 0.28s ease;
  animation: markFloat 8s ease-in-out infinite;
}

.hero-mark img {
  width: 100%;
  height: 100%;
  filter: brightness(1.35) saturate(0.82);
  transform: rotate(-4deg) scale(1);
  transition: transform 0.32s ease, filter 0.32s ease;
}

.hero-mark:hover {
  opacity: 0.32;
}

.hero-mark:hover img {
  filter: brightness(1.55) saturate(0.95) drop-shadow(0 0 34px rgba(128, 180, 254, 0.24));
  transform: rotate(-2deg) scale(1.035);
}

@keyframes markFloat {
  0%, 100% {
    translate: 0 0;
  }
  50% {
    translate: 0 -12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .hero-mark {
    animation: none;
  }

  .hero-mark,
  .hero-mark img,
  .image-frame {
    transition: none;
  }
}

.hero-eyebrow,
.kicker {
  margin: 0 0 18px;
  color: #2f8cff;
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.hero-intro {
  max-width: 960px;
  margin-bottom: 30px;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 24px;
  font-family: var(--title-font);
  font-size: 40px;
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: 0;
}

.hero h1 {
  max-width: 980px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 40px;
  font-weight: 900;
}

h2 {
  margin-bottom: 16px;
  font-family: var(--title-font);
  font-size: 40px;
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 14px;
  font-family: var(--title-font);
  font-size: 40px;
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: 0;
}

.hero-intro p,
.section-head p,
.solution-copy p {
  max-width: 940px;
  color: var(--soft);
  font-size: clamp(16px, 1.28vw, 20px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.primary-link,
.secondary-link {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 0 18px;
  border-radius: 8px;
  font-weight: 800;
}

.primary-link {
  background: linear-gradient(135deg, var(--blue), #1bbfff);
  box-shadow: 0 18px 44px rgba(22, 100, 255, 0.32);
}

.secondary-link {
  color: #b9d2ff;
  border: 1px solid var(--line-strong);
  background: rgba(22, 100, 255, 0.12);
}

.project-strip {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  margin: 0 0 28px;
  border: 1px solid rgba(128, 180, 254, 0.18);
  border-radius: 8px;
  background: rgba(3, 7, 15, 0.36);
  backdrop-filter: blur(16px);
}

.project-strip article {
  min-height: 86px;
  padding: 18px 20px;
}

.project-strip article + article {
  border-left: 1px solid rgba(128, 180, 254, 0.14);
}

.project-strip span {
  display: block;
  margin-bottom: 8px;
  color: #55a5ff;
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.project-strip strong {
  color: #fff;
  font-size: 16px;
  line-height: 1.35;
}

.thesis-panel {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin: 0 0 34px;
}

.thesis-panel article,
.evidence-grid article,
.decision-trail article,
.comparison-strip article,
.credit-grid article {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: linear-gradient(145deg, rgba(16, 35, 70, 0.74), rgba(5, 11, 21, 0.72));
}

.thesis-panel article {
  min-height: 176px;
  padding: 24px;
}

.thesis-panel span,
.decision-trail span,
.comparison-strip span {
  display: inline-block;
  margin-bottom: 10px;
  color: #55a5ff;
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.thesis-panel strong {
  display: block;
  margin-bottom: 12px;
  color: #fff;
  font-size: 22px;
  line-height: 1.28;
}

.thesis-panel p,
.evidence-grid p,
.decision-trail p,
.why-list dd,
.demo-guide p,
.credit-grid p {
  margin-bottom: 0;
  color: var(--muted);
}

.section {
  position: relative;
  counter-increment: case-section;
  padding: 90px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.07);
}

.section-head {
  position: relative;
  display: grid;
  grid-template-columns: minmax(280px, 0.78fr) minmax(360px, 1fr);
  column-gap: clamp(32px, 5vw, 76px);
  align-items: start;
  margin-bottom: 34px;
  padding-left: 90px;
}

.section-head::before {
  content: counter(case-section, decimal-leading-zero);
  position: absolute;
  top: -10px;
  left: 0;
  color: rgba(128, 180, 254, 0.18);
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 76px;
  font-weight: 900;
  line-height: 0.88;
  letter-spacing: 0;
}

.section-head .kicker {
  grid-column: 1 / -1;
}

.section-head.wide,
.solutions .section-head {
  display: block;
  max-width: 1060px;
}

.section:nth-of-type(3n + 1) {
  --section-accent: #15dccd;
}

.section:nth-of-type(3n + 2) {
  --section-accent: #7d5cff;
}

.section:nth-of-type(3n) {
  --section-accent: #2f8cff;
}

.section::after {
  content: "";
  position: absolute;
  top: 120px;
  right: calc(var(--page-gutter) * -0.5);
  width: 180px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--section-accent, #2f8cff));
  opacity: 0.65;
  pointer-events: none;
}

.image-frame {
  position: relative;
  overflow: hidden;
  margin: 0;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 8px;
  background:
    radial-gradient(ellipse at 50% 0%, rgba(255, 255, 255, 0.13), transparent 34%),
    linear-gradient(145deg, #06090f, #111c2e);
  box-shadow: var(--shadow);
  transition: transform 0.28s ease, border-color 0.28s ease, box-shadow 0.28s ease;
}

.image-frame:has(img) {
  cursor: zoom-in;
}

.image-frame:has(img):hover {
  transform: translateY(-4px);
  border-color: rgba(128, 180, 254, 0.34);
  box-shadow: 0 52px 150px rgba(0, 0, 0, 0.62), 0 0 0 1px rgba(22, 100, 255, 0.08) inset;
}

.image-frame:has(img)::after {
  content: "点击放大";
  position: absolute;
  right: 16px;
  bottom: 16px;
  z-index: 2;
  padding: 6px 10px;
  border: 1px solid rgba(128, 180, 254, 0.35);
  border-radius: 8px;
  color: #d9e7ff;
  background: rgba(3, 7, 15, 0.62);
  backdrop-filter: blur(10px);
  font-size: 12px;
  font-weight: 800;
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 0.18s ease, transform 0.18s ease;
}

.image-frame:has(img):hover::after {
  opacity: 1;
  transform: translateY(0);
}

.image-frame img {
  width: 100%;
  height: auto;
}

.evidence-grid,
.comparison-strip,
.credit-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 22px;
}

.evidence-grid article,
.comparison-strip article,
.credit-grid article {
  min-height: 144px;
  padding: 22px;
}

.evidence-grid strong,
.comparison-strip strong,
.credit-grid strong {
  display: block;
  margin-bottom: 10px;
  color: #fff;
  font-size: 20px;
  line-height: 1.25;
}

.decision-trail {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin: 0 0 26px;
}

.decision-trail article {
  position: relative;
  min-height: 210px;
  padding: 24px;
}

.decision-trail h3 {
  font-size: 28px;
  line-height: 1.18;
}

.decision-trail article::before {
  content: "";
  position: absolute;
  top: 24px;
  right: 24px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 18px rgba(21, 220, 205, 0.7);
}

.why-list {
  display: grid;
  gap: 12px;
  margin: 24px 0 0;
}

.why-list div {
  padding-top: 14px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.why-list dt {
  margin-bottom: 4px;
  color: #8edfff;
  font-weight: 900;
}

.why-list dd {
  margin-left: 0;
}

.solutions {
  width: min(1360px, calc(100vw - (var(--page-gutter) * 2)));
}

.solution-block {
  position: relative;
  display: grid;
  grid-template-columns: minmax(310px, 0.42fr) minmax(0, 1fr);
  gap: clamp(28px, 4vw, 58px);
  align-items: center;
  margin-top: 48px;
  padding: clamp(20px, 3vw, 42px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 8px;
  background: linear-gradient(135deg, rgba(10, 20, 38, 0.9), rgba(4, 9, 17, 0.72));
}

.solution-block::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 4px;
  background: linear-gradient(180deg, var(--cyan), var(--blue));
  opacity: 0.72;
}

.solution-block.reverse {
  grid-template-columns: minmax(0, 1fr) minmax(310px, 0.42fr);
}

.solution-block.reverse .solution-copy {
  order: 2;
}

.solution-copy span {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  margin-bottom: 20px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--violet), var(--blue));
  font-weight: 900;
}

.tall-image {
  align-self: start;
}

.demo-section {
  width: min(1500px, calc(100vw - var(--page-gutter)));
}

.demo-section::before {
  content: "";
  position: absolute;
  inset: 54px calc(var(--page-gutter) * -0.35) auto;
  height: 620px;
  z-index: -1;
  border-radius: 8px;
  background:
    radial-gradient(ellipse at 50% 20%, rgba(22, 100, 255, 0.2), transparent 58%),
    linear-gradient(180deg, rgba(21, 220, 205, 0.05), transparent);
}

.demo-entry {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin: 0 0 18px;
  padding: 20px 22px;
  border: 1px solid rgba(21, 220, 205, 0.32);
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(22, 100, 255, 0.2), rgba(21, 220, 205, 0.09)),
    rgba(4, 10, 20, 0.82);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.34);
}

.demo-entry span {
  display: block;
  margin-bottom: 6px;
  color: #55a5ff;
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.demo-entry strong {
  display: block;
  color: #fff;
  font-family: var(--title-font);
  font-size: 24px;
  line-height: 1.24;
}

.demo-entry a {
  flex: 0 0 auto;
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  padding: 0 22px;
  border-radius: 8px;
  color: #fff;
  background: linear-gradient(135deg, var(--blue), #13bddd);
  font-weight: 900;
  box-shadow: 0 18px 52px rgba(22, 100, 255, 0.36);
}

.demo-shell {
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
  background: #07101a;
  box-shadow: 0 64px 180px rgba(0, 0, 0, 0.68), 0 0 0 1px rgba(21, 220, 205, 0.06) inset;
}

.demo-toolbar {
  height: 52px;
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 0 18px;
  color: var(--soft);
  background: rgba(255, 255, 255, 0.05);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 14px;
}

.traffic {
  display: inline-flex;
  gap: 7px;
}

.traffic i {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.traffic i:nth-child(1) { background: #ff5f57; }
.traffic i:nth-child(2) { background: #ffbd2f; }
.traffic i:nth-child(3) { background: #28c840; }

.demo-toolbar span {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.demo-toolbar a {
  min-height: 34px;
  display: inline-flex;
  align-items: center;
  padding: 0 14px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  color: #b9d2ff;
  background: rgba(22, 100, 255, 0.12);
  font-weight: 700;
}

.demo-shell iframe {
  display: block;
  width: 100%;
  height: min(860px, 82vh);
  border: 0;
  background: #fff;
}

.demo-guide {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 24px;
  margin-top: 22px;
  padding: 24px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  background: linear-gradient(135deg, rgba(22, 100, 255, 0.18), rgba(21, 220, 205, 0.08));
}

.demo-guide strong {
  color: #fff;
  font-size: 20px;
}

.demo-guide ol {
  display: grid;
  gap: 8px;
  margin: 0;
  padding-left: 20px;
  color: var(--soft);
}

.demo-guide p {
  grid-column: 2;
  font-size: 14px;
}

.demo-notes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  margin-top: 22px;
}

.demo-notes article {
  min-height: 150px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: linear-gradient(145deg, rgba(20, 45, 92, 0.78), rgba(9, 16, 30, 0.7));
}

.demo-notes strong {
  display: block;
  margin-bottom: 10px;
  color: #fff;
  font-size: 18px;
}

.demo-notes span {
  color: var(--muted);
}

.reflection-section {
  padding-bottom: 130px;
}

.credit-grid article {
  min-height: 180px;
}

a:focus-visible,
button:focus-visible,
iframe:focus-visible,
.image-frame:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 120;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 48px;
  background: rgba(1, 5, 12, 0.88);
  backdrop-filter: blur(20px);
}

.lightbox.open {
  display: flex;
}

.lightbox img {
  max-width: min(96vw, 1680px);
  max-height: 88vh;
  width: auto;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 40px 140px rgba(0, 0, 0, 0.76);
}

.lightbox-close {
  position: fixed;
  top: 22px;
  right: 22px;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  color: #fff;
  background: rgba(10, 20, 38, 0.82);
  font-size: 26px;
  line-height: 1;
}

@media (max-width: 980px) {
  :root {
    --page-gutter: 32px;
  }

  .site-header {
    position: sticky;
    overflow-x: auto;
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
    padding: 14px var(--page-gutter);
  }

  .page-nav {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 2px;
  }

  .page-nav a {
    flex: 0 0 auto;
  }

  .hero {
    padding-top: 72px;
    min-height: auto;
  }

  .section {
    padding: 62px 0;
  }

  .section-head {
    padding-left: 0;
  }

  .section-head::before,
  .section::after,
  .hero-mark {
    display: none;
  }

  .section-head,
  .solution-block,
  .solution-block.reverse,
  .demo-entry,
  .demo-guide {
    display: block;
  }

  .solution-block.reverse .solution-copy {
    order: initial;
  }

  .solution-copy {
    margin-bottom: 24px;
  }

  .demo-notes {
    grid-template-columns: 1fr;
  }

  .thesis-panel,
  .project-strip,
  .evidence-grid,
  .decision-trail,
  .comparison-strip,
  .credit-grid {
    grid-template-columns: 1fr;
  }

  .project-strip article + article {
    border-left: 0;
    border-top: 1px solid rgba(128, 180, 254, 0.14);
  }

  .demo-guide ol {
    margin-top: 12px;
  }

  .demo-entry a {
    width: 100%;
    margin-top: 16px;
  }

  .demo-guide p {
    margin-top: 14px;
  }
}

@media (max-width: 640px) {
  :root {
    --page-gutter: 12px;
  }

  .hero,
  .section,
  .solutions,
  .demo-section {
    width: min(100vw - (var(--page-gutter) * 2), 1360px);
  }

  h1 {
    font-size: 40px;
  }

  h2 {
    font-size: 40px;
  }

  .hero-intro p,
  .section-head p,
  .solution-copy p {
    font-size: 15px;
  }

  .solution-block {
    padding: 16px;
  }

  .demo-shell iframe {
    height: 620px;
  }

  .hero-actions a {
    width: 100%;
  }

  .thesis-panel article,
  .evidence-grid article,
  .decision-trail article,
  .comparison-strip article,
  .credit-grid article,
  .demo-guide {
    padding: 18px;
  }

  .lightbox {
    padding: 16px;
  }

  .lightbox img {
    max-width: 96vw;
    max-height: 84vh;
  }
}