:root {
  --bg: #020713;
  --panel: rgba(4, 20, 38, 0.76);
  --panel-strong: rgba(4, 24, 45, 0.9);
  --line: rgba(171, 231, 255, 0.18);
  --line-strong: rgba(171, 231, 255, 0.32);
  --ink: #f2fbff;
  --muted: #a9c6d8;
  --soft: #d6f7ff;
  --accent: #67f2ff;
  --accent-strong: #27dfff;
  --warm: #ffb66e;
  --green: #6ee6b4;
  color-scheme: dark;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
  letter-spacing: 0;
}

html {
  scroll-behavior: auto;
}

body {
  margin: 0;
  min-width: 320px;
  color: var(--ink);
  background: var(--bg);
  overflow-x: hidden;
}

body.modal-open {
  overflow: hidden;
}

button,
a {
  font: inherit;
}

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

button {
  cursor: pointer;
}

button:focus-visible,
a:focus-visible {
  outline: 3px solid rgba(255, 182, 110, 0.72);
  outline-offset: 3px;
}

.ocean-scene {
  position: fixed;
  inset: 0;
  z-index: 0;
  width: 100%;
  height: 100dvh;
  overflow: hidden;
  background: #020713;
  pointer-events: none;
}

.ocean-scene canvas,
.scroll-frame-canvas,
.scroll-video {
  display: block;
  width: 100%;
  height: 100%;
}

.scroll-frame-canvas {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 220ms ease;
}

.scroll-frame-canvas.is-ready {
  opacity: 1;
}

.scroll-video {
  position: absolute;
  inset: 0;
  object-fit: cover;
  object-position: center;
  opacity: 0;
  filter: saturate(1.08) contrast(1.05) brightness(0.86);
  transform: scale(1.01);
  transition: opacity 360ms ease;
}

.scroll-video.is-ready {
  opacity: 1;
}

.ocean-scene::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(2, 7, 19, 0.98), rgba(2, 12, 25, 0.66) 42%, rgba(2, 14, 26, 0.22) 82%),
    linear-gradient(180deg, rgba(2, 7, 19, 0.34), rgba(2, 7, 19, 0.04) 38%, rgba(2, 7, 19, 0.88));
  pointer-events: none;
}

.no-video .ocean-scene::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, rgba(103, 242, 255, 0.16), transparent 42%),
    repeating-linear-gradient(115deg, rgba(103, 242, 255, 0.08) 0 1px, transparent 1px 22px),
    linear-gradient(180deg, #041d34, #020713 72%);
}

.site-shell {
  position: relative;
  z-index: 1;
  min-height: 100dvh;
}

.site-header {
  position: fixed;
  top: 16px;
  left: 50%;
  z-index: 20;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  width: min(1180px, calc(100% - 32px));
  min-height: 64px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(2, 9, 20, 0.7);
  box-shadow: 0 18px 70px rgba(0, 0, 0, 0.28);
  backdrop-filter: blur(22px) saturate(145%);
  transform: translateX(-50%);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
  color: var(--ink);
  font-size: 0.86rem;
  font-weight: 700;
  white-space: nowrap;
}

.brand img {
  display: block;
  width: 148px;
  height: auto;
  max-height: 34px;
  object-fit: contain;
}

.nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 4px;
  min-width: 0;
}

.nav a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 12px;
  border-radius: 6px;
  color: #d8ecf6;
  font-size: 0.92rem;
  white-space: nowrap;
  transition: background 180ms ease, color 180ms ease;
}

.nav a:hover {
  color: var(--ink);
  background: rgba(103, 242, 255, 0.12);
}

.header-actions {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 8px;
}

.primary-button,
.secondary-button,
.ghost-button,
.icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border-radius: 8px;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease, color 160ms ease;
}

.primary-button:active,
.secondary-button:active,
.ghost-button:active,
.icon-button:active {
  transform: translateY(1px) scale(0.99);
}

.primary-button {
  min-height: 48px;
  padding: 0 18px;
  border: 0;
  color: #02101f;
  font-weight: 800;
  white-space: nowrap;
  background: linear-gradient(135deg, #f2fbff, #67f2ff 57%, #ffb66e);
  box-shadow: 0 18px 44px rgba(39, 223, 255, 0.25);
}

.primary-button:hover {
  background: linear-gradient(135deg, #ffffff, #91f8ff 57%, #ffc78e);
}

.secondary-button,
.ghost-button {
  border: 1px solid var(--line-strong);
  color: var(--ink);
  background: rgba(3, 18, 34, 0.58);
}

.secondary-button {
  min-height: 48px;
  padding: 0 18px;
  font-weight: 700;
  white-space: nowrap;
}

.ghost-button {
  min-height: 42px;
  padding: 0 14px;
  color: #ddf6ff;
  font-weight: 700;
}

.secondary-button:hover,
.ghost-button:hover,
.icon-button:hover {
  border-color: rgba(103, 242, 255, 0.7);
  background: rgba(21, 76, 104, 0.45);
}

.icon-button {
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--line-strong);
  color: var(--ink);
  background: rgba(3, 18, 34, 0.58);
}

.menu-button {
  display: none;
}

.hero-section {
  display: grid;
  grid-template-columns: minmax(0, 670px) minmax(280px, 380px);
  align-items: end;
  gap: 40px;
  min-height: 92dvh;
  padding: 128px max(24px, calc((100vw - 1180px) / 2)) 62px;
}

.hero-content {
  max-width: 670px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  max-width: 100%;
  min-height: 44px;
  padding: 7px 12px 7px 8px;
  border: 1px solid rgba(103, 242, 255, 0.3);
  border-radius: 8px;
  color: #dffaff;
  background: rgba(3, 18, 34, 0.62);
  backdrop-filter: blur(16px);
}

.hero-badge img {
  width: 30px;
  height: 30px;
  object-fit: contain;
}

.hero-badge span {
  overflow: hidden;
  font-size: 0.92rem;
  font-weight: 800;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.hero-content h1 {
  max-width: 8.2em;
  margin: 26px 0 24px;
  font-size: 5.2rem;
  line-height: 1.03;
  font-weight: 900;
  text-wrap: balance;
  text-shadow: 0 12px 54px rgba(18, 205, 244, 0.26);
}

.hero-content p {
  max-width: 600px;
  margin: 0;
  color: #c4dce8;
  font-size: 1.08rem;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.hero-metrics {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(171, 231, 255, 0.14);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.24);
  backdrop-filter: blur(18px);
}

.hero-metrics span {
  display: grid;
  gap: 8px;
  min-height: 92px;
  padding: 18px;
  color: var(--muted);
  background: rgba(4, 20, 38, 0.72);
}

.hero-metrics strong {
  color: var(--warm);
  font-size: 1.6rem;
  line-height: 1;
}

@media (min-width: 1200px) {
  .site-header {
    left: clamp(32px, 5vw, 96px);
    right: clamp(32px, 5vw, 96px);
    width: auto;
    min-height: 70px;
    padding: 0 18px;
    grid-template-columns: minmax(300px, auto) minmax(420px, 1fr) auto;
    transform: none;
  }

  .brand img {
    width: 166px;
    max-height: 38px;
  }

  .brand span {
    font-size: 0.95rem;
  }

  .nav {
    justify-content: flex-start;
    gap: clamp(8px, 1vw, 20px);
    padding-left: clamp(24px, 4vw, 92px);
  }

  .nav a {
    min-height: 44px;
    padding: 0 10px;
    font-size: 0.98rem;
  }

  .hero-section {
    grid-template-columns: minmax(560px, 760px) minmax(360px, 480px);
    justify-content: start;
    align-items: end;
    gap: clamp(96px, 14vw, 260px);
    padding: 136px clamp(56px, 6vw, 128px) 76px;
  }

  .hero-content {
    max-width: 760px;
  }

  .hero-content h1 {
    max-width: 8.7em;
    font-size: clamp(5.2rem, 5.8vw, 7.2rem);
  }

  .hero-content p {
    max-width: 660px;
  }

  .hero-metrics {
    width: min(420px, 100%);
    justify-self: end;
  }

  .section-inner,
  .site-footer {
    width: min(1440px, calc(100% - clamp(112px, 12vw, 220px)));
  }
}

.section {
  position: relative;
  padding: 112px 24px 96px;
  background: linear-gradient(180deg, rgba(2, 7, 19, 0.04), rgba(2, 7, 19, 0.64));
}

.section[id] {
  scroll-margin-top: 104px;
}

.section-inner {
  width: min(1180px, 100%);
  margin: 0 auto;
}

.section-copy {
  max-width: 680px;
}

.narrow-copy {
  max-width: 760px;
}

.section-kicker {
  margin: 0 0 16px;
  color: var(--accent);
  font-size: 0.92rem;
  font-weight: 800;
}

.section-copy h2,
.finals-content h2,
.modal-panel h2 {
  margin: 0;
  color: var(--ink);
  font-size: 3rem;
  line-height: 1.16;
  font-weight: 900;
  text-wrap: balance;
}

.section-copy p,
.overview-copy p,
.track-card p,
.timeline-item p,
.score-row p,
.faq-answer p,
.finals-content p,
.modal-panel p {
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.78;
}

.overview-grid,
.review-grid,
.faq-grid,
.finals-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 60px;
  align-items: start;
}

.overview-copy {
  display: grid;
  gap: 22px;
  padding-left: 28px;
  border-left: 1px solid rgba(103, 242, 255, 0.32);
}

.overview-copy p {
  margin: 0;
  max-width: 64ch;
  color: #d0e4ef;
}

.track-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin-top: 42px;
}

.track-card {
  min-height: 244px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(4, 20, 38, 0.75);
  backdrop-filter: blur(18px);
}

.track-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(103, 242, 255, 0.24);
  border-radius: 8px;
  color: #02101f;
  background: linear-gradient(135deg, var(--accent), var(--green));
}

.track-card h3,
.timeline-item h3,
.score-row h3 {
  margin: 22px 0 10px;
  color: var(--ink);
  font-size: 1.15rem;
  line-height: 1.36;
}

.track-card p,
.timeline-item p,
.score-row p {
  margin: 0;
}

.timeline {
  display: grid;
  margin-top: 42px;
  border-top: 1px solid var(--line-strong);
}

.timeline-item {
  display: grid;
  grid-template-columns: 210px minmax(180px, 280px) minmax(0, 1fr);
  gap: 24px;
  padding: 24px 0;
  border-bottom: 1px solid rgba(171, 231, 255, 0.18);
}

.timeline-item time {
  color: var(--warm);
  font-weight: 800;
}

.timeline-item h3 {
  margin: 0;
}

.score-list {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(4, 20, 38, 0.72);
  backdrop-filter: blur(18px);
}

.score-row {
  display: grid;
  grid-template-columns: 92px 1fr;
  gap: 20px;
  padding: 20px 22px;
}

.score-row + .score-row {
  border-top: 1px solid rgba(171, 231, 255, 0.14);
}

.score-value {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 68px;
  height: 44px;
  border-radius: 8px;
  color: #02101f;
  font-weight: 900;
  background: var(--warm);
}

.score-row h3 {
  margin: 0 0 6px;
}

.finals-section {
  background: linear-gradient(180deg, rgba(2, 7, 19, 0.5), rgba(9, 37, 50, 0.62));
}

.finals-layout {
  align-items: center;
}

.finals-mark {
  display: grid;
  gap: 24px;
  color: var(--accent);
}

.finals-mark span {
  max-width: 520px;
  color: var(--ink);
  font-size: 4rem;
  line-height: 1.08;
  font-weight: 900;
  text-wrap: balance;
}

.finals-anchor {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 96px;
  height: 96px;
  padding: 8px;
  border: 1px solid rgba(103, 242, 255, 0.38);
  border-radius: 8px;
  background:
    radial-gradient(circle at 50% 38%, rgba(103, 242, 255, 0.24), transparent 58%),
    rgba(4, 20, 38, 0.72);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.12), 0 22px 60px rgba(39, 223, 255, 0.16);
}

.finals-anchor img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  filter: drop-shadow(0 10px 18px rgba(0, 0, 0, 0.36));
}

.finals-steps {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin-top: 32px;
}

.finals-steps span {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 58px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: #e4f7ff;
  font-weight: 800;
  text-align: center;
  background: rgba(4, 20, 38, 0.64);
}

.faq-list {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(4, 20, 38, 0.72);
  backdrop-filter: blur(18px);
}

.faq-item + .faq-item {
  border-top: 1px solid rgba(171, 231, 255, 0.14);
}

.faq-item button {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  min-height: 66px;
  padding: 0 22px;
  border: 0;
  color: var(--ink);
  font-weight: 800;
  text-align: left;
  background: transparent;
}

.faq-item button b {
  flex: 0 0 auto;
  color: var(--accent);
  font-size: 0.86rem;
  font-weight: 800;
  transition: color 180ms ease;
}

.faq-item.is-active button b {
  color: var(--warm);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 220ms ease;
}

.faq-answer p {
  margin: 0;
  padding: 0 22px 22px;
}

.faq-item.is-active .faq-answer {
  max-height: 180px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
  padding: 34px 0 48px;
  border-top: 1px solid var(--line);
}

.site-footer img {
  display: block;
  width: 158px;
  height: auto;
  margin-bottom: 10px;
}

.site-footer p {
  margin: 0;
  color: var(--muted);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px;
}

.footer-links span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 38px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: #dff8ff;
  background: rgba(4, 20, 38, 0.58);
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 520ms ease, transform 520ms ease;
}

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

.modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 20px;
  background: rgba(0, 5, 12, 0.72);
  backdrop-filter: blur(12px);
}

.modal-backdrop[hidden] {
  display: none;
}

.modal-panel {
  position: relative;
  width: min(560px, 100%);
  padding: 32px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  background: rgba(4, 20, 38, 0.95);
  box-shadow: 0 30px 100px rgba(0, 0, 0, 0.42);
}

.modal-panel h2 {
  font-size: 2rem;
}

.modal-panel p {
  margin: 16px 0 0;
}

.modal-close {
  position: absolute;
  top: 16px;
  right: 16px;
}

.modal-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 26px;
}

@media (max-width: 1100px) {
  .site-header {
    grid-template-columns: auto auto;
    justify-content: space-between;
  }

  .nav {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    display: none;
    width: min(280px, calc(100vw - 32px));
    padding: 10px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: rgba(2, 9, 20, 0.94);
    box-shadow: 0 22px 80px rgba(0, 0, 0, 0.36);
    backdrop-filter: blur(22px);
  }

  .nav.is-open {
    display: grid;
  }

  .nav a {
    justify-content: flex-start;
    width: 100%;
  }

  .menu-button {
    display: inline-flex;
  }

  .hero-section {
    grid-template-columns: 1fr;
    gap: 28px;
    padding-top: 118px;
  }

  .hero-metrics {
    max-width: 540px;
  }

  .track-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .overview-grid,
  .review-grid,
  .faq-grid,
  .finals-layout {
    grid-template-columns: 1fr;
    gap: 38px;
  }

  .timeline-item {
    grid-template-columns: 170px minmax(150px, 220px) minmax(0, 1fr);
  }
}

@media (max-width: 720px) {
  .site-header {
    top: 8px;
    width: calc(100% - 16px);
    min-height: 60px;
    padding: 0 10px;
  }

  .brand img {
    width: 118px;
    max-height: 30px;
  }

  .brand span {
    display: none;
  }

  .ghost-button {
    display: none;
  }

  .hero-section {
    min-height: 94dvh;
    padding: 104px 16px 42px;
  }

  .hero-content h1 {
    max-width: 7.8em;
    margin: 22px 0 18px;
    font-size: 3rem;
    line-height: 1.12;
  }

  .hero-content p {
    font-size: 1rem;
    line-height: 1.72;
  }

  .hero-actions,
  .modal-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .primary-button,
  .secondary-button {
    width: 100%;
  }

  .hero-metrics {
    grid-template-columns: 1fr 1fr;
  }

  .hero-metrics span {
    min-height: 82px;
    padding: 14px;
    font-size: 0.86rem;
  }

  .hero-metrics strong {
    font-size: 1.32rem;
  }

  .section {
    padding: 76px 16px 68px;
  }

  .section-copy h2,
  .finals-content h2 {
    font-size: 2rem;
    line-height: 1.22;
  }

  .overview-copy {
    padding-left: 16px;
  }

  .track-grid,
  .finals-steps {
    grid-template-columns: 1fr;
  }

  .track-card {
    min-height: auto;
  }

  .timeline-item {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 22px 0;
  }

  .score-row {
    grid-template-columns: 74px 1fr;
    gap: 14px;
    padding: 18px 16px;
  }

  .score-value {
    width: 58px;
    height: 40px;
    font-size: 0.9rem;
  }

  .finals-mark span {
    font-size: 2.6rem;
  }

  .faq-item button {
    min-height: 62px;
    padding: 0 16px;
  }

  .faq-answer p {
    padding: 0 16px 18px;
  }

  .site-footer {
    display: grid;
    width: calc(100% - 32px);
  }

  .footer-links {
    justify-content: flex-start;
  }

  .modal-panel {
    padding: 28px 18px 20px;
  }

  .modal-panel h2 {
    padding-right: 42px;
    font-size: 1.55rem;
  }
}

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

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

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