:root {
  --indigo: #1E3A6D;
  --indigo-deep: #152A52;
  --indigo-soft: #2A4A7A;
  --cream: #F3F0E6;
  --cream-deep: #E8E3D4;
  --ink: #1A2238;
  --mute: #5C6478;
  --red: #A33B32;
  --white: #FFFEF9;
  --line: rgba(30, 58, 109, 0.14);
  --glow: rgba(30, 58, 109, 0.12);
  --radius: 20px;
  --pill: 999px;
  --max: 1200px;
  --font: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--cream);
  line-height: 1.7;
  font-size: 16px;
}

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

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

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

.container {
  width: min(100% - 64px, var(--max));
  margin-inline: auto;
}

.skip {
  position: absolute;
  left: -999px;
}

.skip:focus {
  left: 16px;
  top: 16px;
  z-index: 100;
  background: var(--white);
  padding: 8px 12px;
}

/* indigo dye cloth */
.dye {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 50% 42%, rgba(255, 254, 249, 0.96) 0 11%, transparent 12%),
    radial-gradient(circle at 50% 18%, rgba(243, 240, 230, 0.92) 0 7%, transparent 8%),
    radial-gradient(circle at 22% 48%, rgba(243, 240, 230, 0.88) 0 8%, transparent 9%),
    radial-gradient(circle at 78% 48%, rgba(243, 240, 230, 0.88) 0 8%, transparent 9%),
    radial-gradient(circle at 84% 86%, rgba(243, 240, 230, 0.7) 0 6%, transparent 7%),
    radial-gradient(ellipse 120% 90% at 50% 40%, var(--indigo-soft) 0%, var(--indigo) 42%, var(--indigo-deep) 100%);
}

.dye::before {
  content: "";
  position: absolute;
  inset: -20% -10%;
  background:
    radial-gradient(circle at 50% 42%, transparent 10.5%, rgba(243, 240, 230, 0.22) 11%, transparent 13%),
    radial-gradient(circle at 50% 42%, transparent 18%, rgba(243, 240, 230, 0.14) 19%, transparent 22%),
    radial-gradient(circle at 50% 42%, transparent 28%, rgba(243, 240, 230, 0.1) 29%, transparent 33%),
    radial-gradient(circle at 18% 78%, rgba(163, 59, 50, 0.35) 0 1.2%, transparent 1.8%),
    radial-gradient(circle at 50% 18%, transparent 6%, rgba(243, 240, 230, 0.18) 7%, transparent 9%),
    radial-gradient(circle at 22% 48%, transparent 7%, rgba(243, 240, 230, 0.16) 8%, transparent 10%),
    radial-gradient(circle at 78% 48%, transparent 7%, rgba(243, 240, 230, 0.16) 8%, transparent 10%);
  pointer-events: none;
}

.dye > * {
  position: relative;
  z-index: 1;
}

.ring-label {
  position: absolute;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: rgba(243, 240, 230, 0.72);
  pointer-events: none;
  white-space: nowrap;
}

.ring-label.is-red {
  color: var(--red);
  font-weight: 600;
}

.ring-c { left: 50%; top: 38%; transform: translate(-50%, -50%); color: var(--cream); font-size: 13px; font-weight: 600; }
.ring-t { left: 50%; top: 11%; transform: translateX(-50%); }
.ring-l { left: 8%; top: 46%; }
.ring-r { right: 8%; top: 46%; }
.ring-b { right: 6%; bottom: 8%; color: rgba(243, 240, 230, 0.55); }

/* header */
.header {
  position: fixed;
  inset: 0 0 auto;
  height: 64px;
  z-index: 50;
  background: rgba(243, 240, 230, 0.82);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.nav {
  height: 64px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
  width: min(100% - 48px, var(--max));
  margin-inline: auto;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  justify-self: start;
}

.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  overflow: hidden;
  background: var(--indigo);
  flex-shrink: 0;
}

.brand-mark img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.brand-name {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--indigo);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 36px;
  justify-self: center;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  font-size: 14px;
  color: var(--mute);
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--indigo);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  justify-self: end;
}

.btn-ghost {
  font-size: 14px;
  color: var(--indigo);
  padding: 8px 14px;
}

.btn-solid {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 22px;
  border-radius: var(--pill);
  background: var(--indigo);
  color: var(--cream);
  font-size: 14px;
  font-weight: 500;
}

.btn-solid:hover {
  background: var(--indigo-deep);
}

.btn-solid.lg {
  min-height: 48px;
  padding: 0 28px;
  font-size: 16px;
}

.menu-btn {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: 8px;
  border: 1px solid var(--line);
  align-items: center;
  justify-content: center;
  color: var(--indigo);
}

.menu-btn span,
.menu-btn span::before,
.menu-btn span::after {
  display: block;
  width: 16px;
  height: 1.5px;
  background: currentColor;
  position: relative;
}

.menu-btn span::before,
.menu-btn span::after {
  content: "";
  position: absolute;
  left: 0;
}

.menu-btn span::before { top: -5px; }
.menu-btn span::after { top: 5px; }

.drawer {
  display: none;
  position: fixed;
  inset: 64px 0 auto;
  background: rgba(243, 240, 230, 0.98);
  border-bottom: 1px solid var(--line);
  padding: 16px 24px 24px;
  z-index: 49;
}

.drawer.is-open { display: block; }

.drawer a {
  display: block;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
  color: var(--indigo);
  font-size: 15px;
}

/* hero */
.hero {
  padding: 140px 0 72px;
  text-align: center;
}

.hero-title {
  margin: 0 auto 20px;
  max-width: 900px;
  font-size: clamp(36px, 5.5vw, 64px);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.15;
  color: var(--cream);
}

.hero-lead {
  margin: 0 auto 28px;
  max-width: 560px;
  color: rgba(243, 240, 230, 0.82);
  font-weight: 300;
  font-size: 16px;
}

.hero-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  margin-bottom: 48px;
}

.hero-actions .btn-solid {
  background: var(--cream);
  color: var(--indigo);
}

.hero-actions .btn-solid:hover {
  background: var(--white);
}

.hero-link {
  color: #F0D2CF;
  font-size: 14px;
  font-weight: 400;
  border-bottom: 1px solid rgba(163, 59, 50, 0.45);
}

.hero-shot-wrap {
  position: relative;
  max-width: 1000px;
  margin: 0 auto;
}

.hero-glow {
  position: absolute;
  left: 50%;
  top: 40%;
  width: 70%;
  height: 70%;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, rgba(243, 240, 230, 0.35), transparent 70%);
  filter: none;
  pointer-events: none;
}

.hero-shot {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid rgba(243, 240, 230, 0.28);
  box-shadow: 0 24px 60px rgba(10, 20, 40, 0.35);
  background: var(--cream);
}

.hero-shot img {
  width: 100%;
}

/* section commons */
.section {
  padding: 96px 0;
}

.section-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 40px;
  margin-bottom: 28px;
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 28px;
  padding: 0 14px;
  border-radius: var(--pill);
  background: rgba(30, 58, 109, 0.08);
  color: var(--indigo);
  font-size: 13px;
}

.section-title {
  margin: 12px 0 0;
  font-size: clamp(32px, 4vw, 52px);
  font-weight: 500;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--indigo);
}

.section-sub {
  max-width: 400px;
  margin: 0;
  color: var(--mute);
  font-size: 16px;
  font-weight: 300;
}

.center-copy {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 36px;
}

.center-copy .section-title {
  margin-top: 12px;
}

.center-copy p {
  color: var(--mute);
}

/* tabs + scenario */
.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 6px;
  background: rgba(30, 58, 109, 0.06);
  border-radius: var(--pill);
  width: fit-content;
  margin-bottom: 20px;
}

.tab {
  border-radius: var(--pill);
  padding: 10px 18px;
  font-size: 14px;
  color: var(--mute);
}

.tab.is-on {
  background: var(--white);
  color: var(--ink);
  box-shadow: 0 1px 4px rgba(30, 58, 109, 0.08);
}

.scenario-card {
  display: grid;
  grid-template-columns: 30% 70%;
  min-height: 420px;
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--white);
  border: 1px solid var(--line);
}

.scenario-text {
  padding: 36px 32px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 14px;
  background: var(--cream);
}

.scenario-text h3 {
  margin: 0;
  font-size: 26px;
  font-weight: 500;
  line-height: 1.35;
  color: var(--indigo);
}

.scenario-text p {
  margin: 0;
  color: var(--mute);
  font-size: 15px;
}

.scenario-visual {
  background: #E8EDF5;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.scenario-visual img {
  width: 100%;
  border-radius: 12px;
}

.pane { display: none; }
.pane.is-on { display: contents; }

/* eco */
.eco {
  background: var(--cream-deep);
}

.eco-band {
  background: linear-gradient(180deg, rgba(30, 58, 109, 0.06), transparent);
  border-radius: var(--radius);
  padding: 56px 24px;
}

.logo-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
}

.logo-chip {
  min-width: 120px;
  padding: 16px 20px;
  border-radius: 12px;
  background: var(--white);
  border: 1px solid var(--line);
  text-align: center;
  color: var(--indigo);
  font-size: 14px;
  font-weight: 500;
}

/* trust */
.trust-band {
  background: #E7EDF6;
  border-radius: var(--radius);
  padding: 48px 40px;
}

.trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 28px;
}

.trust-card {
  background: var(--white);
  border-radius: var(--radius);
  padding: 32px;
  border: 1px solid rgba(30, 58, 109, 0.08);
}

.trust-card h3 {
  margin: 0 0 10px;
  font-size: 19px;
  font-weight: 500;
  color: var(--indigo);
}

.trust-card p {
  margin: 0;
  color: var(--mute);
  font-size: 14px;
}

/* download section */
.download-section .pill {
  background: #E7EDF6;
}

.dl-groups {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  margin-top: 36px;
}

.dl-group-label {
  display: block;
  margin-bottom: 16px;
  color: var(--mute);
  font-size: 14px;
}

.dl-tiles {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.dl-tile {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px;
  border-radius: 14px;
  background: var(--white);
  border: 1px solid var(--line);
  position: relative;
}

.dl-ico {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--indigo);
  color: var(--cream);
  display: grid;
  place-items: center;
  font-size: 12px;
  font-weight: 700;
  flex-shrink: 0;
}

.dl-tile strong {
  display: block;
  font-size: 15px;
  color: var(--ink);
}

.dl-tile span {
  font-size: 12px;
  color: var(--mute);
}

.badge {
  position: absolute;
  top: 8px;
  right: 8px;
  font-size: 11px;
  padding: 2px 8px;
  border-radius: var(--pill);
  background: var(--red);
  color: #fff;
}

/* page hero variants */
.page-hero {
  padding: 120px 0 64px;
}

.page-hero .hero-title {
  font-size: clamp(32px, 4.5vw, 48px);
}

.page-body {
  padding: 64px 0 96px;
}

.article {
  max-width: 760px;
}

.article h2 {
  margin: 36px 0 12px;
  font-size: 28px;
  color: var(--indigo);
  font-weight: 500;
}

.article p {
  color: var(--mute);
  margin: 0 0 14px;
}

.article ul {
  color: var(--mute);
  padding-left: 1.2em;
}

.article li {
  margin-bottom: 8px;
}

.help-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 28px;
}

.help-card {
  padding: 24px;
  border-radius: 14px;
  background: var(--white);
  border: 1px solid var(--line);
}

.help-card h3 {
  margin: 0 0 8px;
  font-size: 18px;
  color: var(--indigo);
}

.help-card p {
  margin: 0;
  color: var(--mute);
  font-size: 14px;
}

.entry-box {
  max-width: 640px;
  margin: 40px auto 0;
  padding: 32px;
  border-radius: var(--radius);
  background: var(--white);
  border: 1px solid var(--line);
  text-align: center;
}

.entry-box p {
  color: var(--mute);
  margin: 0 0 20px;
}

.entry-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border-radius: var(--pill);
  border: 1px solid var(--indigo);
  color: var(--indigo);
  font-size: 14px;
}

/* footer */
.footer {
  background: #0E1628;
  color: #BFBFBF;
  padding: 56px 0 0;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-brand {
  max-width: 320px;
}

.footer-brand .brand-name {
  color: var(--cream);
}

.footer-brand p {
  margin: 14px 0 0;
  font-size: 14px;
  color: #9AA3B5;
  line-height: 1.7;
}

.footer-cols {
  display: flex;
  gap: 80px;
}

.footer-col h3 {
  margin: 0 0 14px;
  font-size: 14px;
  color: #fff;
  font-weight: 500;
}

.footer-col a {
  display: block;
  font-size: 13px;
  color: #9AA3B5;
  margin-bottom: 10px;
}

.footer-col a:hover {
  color: var(--cream);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 24px 0;
  font-size: 12px;
  color: #8A93A3;
}

.footer-wordmark {
  text-align: center;
  padding: 24px 0 40px;
  font-size: clamp(48px, 10vw, 120px);
  font-weight: 700;
  letter-spacing: -0.04em;
  color: rgba(243, 240, 230, 0.08);
  line-height: 1;
  user-select: none;
}

/* page dye variants for differentiation */
.page-download .dye {
  background:
    radial-gradient(circle at 28% 55%, rgba(255, 254, 249, 0.95) 0 10%, transparent 11%),
    radial-gradient(circle at 72% 40%, rgba(243, 240, 230, 0.9) 0 8%, transparent 9%),
    radial-gradient(circle at 50% 20%, rgba(243, 240, 230, 0.85) 0 7%, transparent 8%),
    radial-gradient(ellipse 100% 80% at 40% 50%, var(--indigo-soft), var(--indigo-deep));
}

.page-web .dye {
  background:
    radial-gradient(circle at 70% 48%, rgba(255, 254, 249, 0.96) 0 12%, transparent 13%),
    radial-gradient(circle at 30% 30%, rgba(243, 240, 230, 0.88) 0 8%, transparent 9%),
    radial-gradient(ellipse 110% 90% at 60% 45%, #254878, var(--indigo-deep));
}

.page-help .dye {
  background:
    radial-gradient(circle at 50% 60%, rgba(255, 254, 249, 0.94) 0 9%, transparent 10%),
    radial-gradient(circle at 18% 28%, rgba(243, 240, 230, 0.86) 0 7%, transparent 8%),
    radial-gradient(circle at 82% 32%, rgba(243, 240, 230, 0.86) 0 7%, transparent 8%),
    radial-gradient(ellipse 100% 85% at 50% 40%, #1B355F, #101C34);
}

@media (max-width: 968px) {
  .nav-links,
  .nav-actions .btn-ghost {
    display: none;
  }

  .menu-btn {
    display: inline-flex;
    justify-self: end;
  }

  .nav {
    grid-template-columns: 1fr auto;
  }

  .nav-actions {
    display: none;
  }

  .section-head {
    flex-direction: column;
    align-items: flex-start;
  }

  .scenario-card {
    grid-template-columns: 1fr;
  }

  .scenario-visual {
    min-height: 240px;
  }

  .trust-grid,
  .dl-groups,
  .help-grid {
    grid-template-columns: 1fr;
  }

  .footer-top,
  .footer-bottom {
    flex-direction: column;
  }

  .footer-cols {
    flex-wrap: wrap;
    gap: 32px;
  }

  .container {
    width: min(100% - 32px, var(--max));
  }

  .ring-label {
    display: none;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(100% - 16px, var(--max));
  }

  .dl-tiles {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-top: 112px;
  }

  .section {
    padding: 72px 0;
  }

  .trust-band {
    padding: 32px 20px;
  }
}

/* runtime paint budget — keep the look, drop expensive filters */
.hero-glow {
  filter: none;
  contain: paint;
  pointer-events: none;
}
.header {
  -webkit-backdrop-filter: blur(8px);
  contain: layout style;
}
.section,
.eco,
.page-body {
  content-visibility: auto;
  contain-intrinsic-size: auto 720px;
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}
@media (max-width: 640px) {
  .header,
  .drawer,
  .hero-shot,
  .jelly-cube,
  .refraction-seam {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
}