:root {
  color-scheme: light dark;
  --page: #f7faff;
  --surface: #eef5ff;
  --surface-strong: #e4efff;
  --text: #17283e;
  --text-soft: #4d627a;
  --line: #cad9eb;
  --accent: #2f7df6;
  --accent-hover: #2368d4;
  --accent-ink: #f8fbff;
  --shadow: 0 24px 64px rgba(55, 104, 168, 0.14);
  --radius: 18px;
  --header-height: 72px;
  font-family: "Avenir Next", "SF Pro Display", "PingFang SC", "Microsoft YaHei UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 24px);
}

body {
  margin: 0;
  background: var(--page);
  color: var(--text);
  font-size: 16px;
  line-height: 1.7;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-underline-offset: 0.2em;
}

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

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 20;
  transform: translateY(-160%);
  border-radius: 10px;
  background: var(--accent);
  color: var(--accent-ink);
  padding: 10px 14px;
}

.skip-link:focus {
  transform: translateY(0);
}

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 4px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  min-height: var(--header-height);
  border-bottom: 1px solid color-mix(in srgb, var(--line) 82%, transparent);
  background: color-mix(in srgb, var(--page) 90%, transparent);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.header-inner,
.hero,
.section,
.footer-inner {
  width: min(1120px, calc(100% - 40px));
  margin-inline: auto;
}

.header-inner {
  min-height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.brand {
  flex: 0 0 auto;
}

.brand img {
  width: 106px;
}

nav {
  display: flex;
  align-items: center;
  gap: 28px;
  white-space: nowrap;
}

nav a {
  color: var(--text-soft);
  font-size: 14px;
  font-weight: 650;
  text-decoration: none;
}

nav a:hover {
  color: var(--accent);
}

.hero {
  min-height: calc(100dvh - var(--header-height));
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.95fr);
  align-items: center;
  gap: clamp(48px, 8vw, 112px);
  padding-block: clamp(56px, 8vh, 84px);
}

.eyebrow {
  margin: 0 0 18px;
  color: var(--accent);
  font-size: 14px;
  font-weight: 750;
  letter-spacing: 0.08em;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  max-width: 10em;
  margin: 0;
  font-size: clamp(44px, 4.8vw, 62px);
  line-height: 1.08;
  letter-spacing: -0.045em;
}

.hero-text {
  max-width: 32em;
  margin: 26px 0 0;
  color: var(--text-soft);
  font-size: clamp(17px, 1.8vw, 20px);
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-top: 34px;
}

.primary-button {
  display: inline-flex;
  min-height: 50px;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  background: var(--accent);
  color: var(--accent-ink);
  padding: 12px 24px;
  font-weight: 750;
  text-decoration: none;
  white-space: nowrap;
  box-shadow: 0 12px 30px rgba(47, 125, 246, 0.24);
  transition: transform 160ms ease, background-color 160ms ease, box-shadow 160ms ease;
}

.primary-button:hover {
  background: var(--accent-hover);
  box-shadow: 0 16px 36px rgba(47, 125, 246, 0.3);
}

.primary-button:active {
  transform: translateY(1px);
}

.text-link {
  color: var(--text);
  font-weight: 700;
}

.hero-visual {
  position: relative;
  isolation: isolate;
  min-height: 480px;
  display: grid;
  place-items: center;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    radial-gradient(circle at 18% 16%, rgba(47, 125, 246, 0.2), transparent 34%),
    linear-gradient(145deg, var(--surface), var(--page));
  box-shadow: var(--shadow);
}

.hero-visual img {
  position: relative;
  z-index: 2;
  width: min(70%, 330px);
  filter: drop-shadow(0 22px 28px rgba(35, 71, 119, 0.18));
}

.visual-orbit {
  position: absolute;
  border: 1px solid color-mix(in srgb, var(--accent) 35%, transparent);
  border-radius: 50%;
}

.visual-orbit-large {
  width: 390px;
  aspect-ratio: 1;
}

.visual-orbit-small {
  width: 250px;
  aspect-ratio: 1;
}

.visual-note {
  position: absolute;
  right: 24px;
  bottom: 22px;
  z-index: 3;
  color: var(--text-soft);
  font-size: 13px;
  font-weight: 650;
}

.section {
  padding-block: clamp(76px, 10vw, 132px);
}

.section-heading {
  max-width: 660px;
  margin-bottom: 42px;
}

h2 {
  margin: 0;
  font-size: clamp(32px, 4.6vw, 52px);
  line-height: 1.15;
  letter-spacing: -0.035em;
}

.section-heading p,
.account-copy p {
  margin: 16px 0 0;
  color: var(--text-soft);
  font-size: 17px;
}

.support-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(300px, 0.55fr);
  gap: 22px;
}

.support-grid .section-heading {
  grid-column: 1 / -1;
}

.contact-panel,
.prep-panel,
.account-actions article {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.contact-panel {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0;
  padding: clamp(28px, 4vw, 48px);
}

.contact-panel > div + div {
  border-left: 1px solid var(--line);
  padding-left: clamp(24px, 4vw, 48px);
}

.contact-panel > div:first-child {
  padding-right: clamp(24px, 4vw, 48px);
}

.contact-label {
  margin: 0 0 8px;
  color: var(--text-soft);
  font-size: 14px;
  font-weight: 700;
}

.contact-value {
  color: var(--text);
  font-size: clamp(20px, 2vw, 26px);
  font-weight: 780;
  letter-spacing: -0.025em;
}

.contact-help {
  margin: 14px 0 0;
  color: var(--text-soft);
  font-size: 14px;
}

.registered-address {
  grid-column: 1 / -1;
  margin-top: 30px;
  border-top: 1px solid var(--line);
  padding-top: 24px;
  color: var(--text);
  font-style: normal;
}

.registered-address .contact-label {
  display: block;
}

.prep-panel {
  padding: 32px;
  background: var(--surface-strong);
}

.prep-panel h3,
.account-actions h3 {
  margin: 0;
  font-size: 20px;
  letter-spacing: -0.02em;
}

.prep-panel ol {
  counter-reset: prep;
  display: grid;
  gap: 12px;
  margin: 22px 0;
  padding: 0;
  list-style: none;
}

.prep-panel li {
  counter-increment: prep;
  display: grid;
  grid-template-columns: 28px 1fr;
  align-items: start;
  gap: 10px;
}

.prep-panel li::before {
  content: counter(prep);
  display: grid;
  width: 26px;
  height: 26px;
  place-items: center;
  border-radius: 8px;
  background: var(--accent);
  color: var(--accent-ink);
  font-size: 12px;
  font-weight: 800;
}

.prep-panel > p {
  margin: 0;
  color: var(--text-soft);
  font-size: 13px;
}

.faq-section {
  display: grid;
  grid-template-columns: minmax(280px, 0.7fr) minmax(0, 1.3fr);
  align-items: start;
  gap: clamp(48px, 8vw, 104px);
}

.faq-list {
  border-top: 1px solid var(--line);
}

.faq-list details {
  border-bottom: 1px solid var(--line);
}

.faq-list summary {
  position: relative;
  cursor: pointer;
  list-style: none;
  padding: 24px 48px 24px 0;
  font-size: 17px;
  font-weight: 720;
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary::after {
  content: "+";
  position: absolute;
  top: 20px;
  right: 4px;
  color: var(--accent);
  font-size: 26px;
  font-weight: 450;
  line-height: 1;
}

.faq-list details[open] summary::after {
  content: "−";
}

.faq-answer {
  padding: 0 46px 24px 0;
  color: var(--text-soft);
}

.faq-answer p {
  margin: 0;
}

.account-section {
  display: grid;
  grid-template-columns: minmax(260px, 0.72fr) minmax(0, 1.28fr);
  gap: clamp(50px, 8vw, 112px);
  align-items: start;
}

.account-copy {
  position: sticky;
  top: calc(var(--header-height) + 32px);
}

.account-actions {
  display: grid;
  gap: 16px;
}

.account-actions article {
  padding: 28px 30px;
}

.account-actions p {
  margin: 10px 0 0;
  color: var(--text-soft);
}

footer {
  border-top: 1px solid var(--line);
  background: var(--surface);
}

.footer-inner {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 48px;
  padding-block: 48px;
}

.footer-inner img {
  width: 112px;
}

.footer-inner > div:first-child p {
  margin: 12px 0 0;
  color: var(--text-soft);
}

.footer-meta {
  text-align: right;
}

.footer-meta p {
  margin: 0 0 6px;
  color: var(--text-soft);
  font-size: 13px;
}

.footer-meta a:hover {
  color: var(--accent);
}

@media (prefers-color-scheme: dark) {
  :root {
    --page: #111926;
    --surface: #172235;
    --surface-strong: #1b2a42;
    --text: #edf4fd;
    --text-soft: #b2c1d4;
    --line: #344763;
    --accent: #6aa6ff;
    --accent-hover: #8ab9ff;
    --accent-ink: #101927;
    --shadow: 0 24px 64px rgba(3, 11, 24, 0.34);
  }

  .hero-visual {
    background:
      radial-gradient(circle at 18% 16%, rgba(106, 166, 255, 0.24), transparent 34%),
      linear-gradient(145deg, var(--surface-strong), var(--page));
  }

  .hero-visual img {
    filter: drop-shadow(0 22px 28px rgba(2, 8, 18, 0.35));
  }
}

@media (max-width: 820px) {
  .header-inner,
  .hero,
  .section,
  .footer-inner {
    width: min(100% - 32px, 680px);
  }

  nav {
    display: none;
  }

  .hero {
    min-height: auto;
    grid-template-columns: 1fr;
    gap: 42px;
    padding-block: 54px 72px;
  }

  h1 {
    font-size: clamp(38px, 10vw, 48px);
  }

  .hero-visual {
    min-height: 390px;
  }

  .support-grid,
  .faq-section,
  .account-section {
    grid-template-columns: 1fr;
  }

  .account-copy {
    position: static;
  }

  .faq-section {
    gap: 18px;
  }
}

@media (max-width: 560px) {
  .header-inner,
  .hero,
  .section,
  .footer-inner {
    width: calc(100% - 28px);
  }

  .brand img {
    width: 92px;
  }

  .hero {
    padding-top: 42px;
  }

  .hero-actions {
    align-items: flex-start;
    flex-direction: column;
    gap: 16px;
  }

  .hero-visual {
    min-height: 320px;
  }

  .visual-orbit-large {
    width: 310px;
  }

  .visual-orbit-small {
    width: 200px;
  }

  .visual-note {
    right: 18px;
    bottom: 16px;
  }

  .section {
    padding-block: 74px;
  }

  .contact-panel {
    grid-template-columns: 1fr;
    padding: 28px;
  }

  .contact-panel > div:first-child {
    padding-right: 0;
    padding-bottom: 26px;
  }

  .contact-panel > div + div {
    border-top: 1px solid var(--line);
    border-left: 0;
    padding-top: 26px;
    padding-left: 0;
  }

  .contact-value {
    font-size: 20px;
  }

  .prep-panel,
  .account-actions article {
    padding: 26px;
  }

  .footer-inner {
    flex-direction: column;
    gap: 28px;
  }

  .footer-meta {
    text-align: left;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}

@media (prefers-reduced-transparency: reduce) {
  .site-header {
    background: var(--page);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }
}