:root {
  --sg-primary: #00A88E;
  --sg-primary-soft: #7DD8C8;
  --sg-accent: #D4AF37;
  --sg-bg: #1E1E1E;
  --sg-bg-mid: #2A2A2A;
  --sg-text: #F5F5F5;
  --sg-text-muted: #A0A0A0;
  --sg-border: rgba(255, 255, 255, 0.08);
  --sg-gold-border: rgba(212, 175, 55, 0.45);
  --sg-gradient: linear-gradient(135deg, #00A88E 0%, #D4AF37 100%);
  --sg-shadow: 0 18px 32px rgba(0, 0, 0, 0.35);
  --sg-radius: 14px;
  --sg-font-serif: "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --sg-font-sans: "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --sg-font-mono: "SF Mono", "Cascadia Code", "Roboto Mono", monospace;
  --sg-page-width: 1200px;
  --sg-header-h: 72px;
  --sg-z-header: 100;
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--sg-bg);
  color: var(--sg-text);
  font-family: var(--sg-font-sans);
  font-size: 1rem;
  line-height: 1.75;
}

h1, h2, h3, h4, p, ul, ol, figure, blockquote {
  margin: 0;
}

ul, ol {
  padding: 0;
}

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

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

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

:focus-visible {
  outline: 2px solid var(--sg-accent);
  outline-offset: 2px;
  border-radius: 4px;
}

.sg-visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  border: 0;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  overflow: hidden;
  white-space: nowrap;
}

.sg-container {
  width: min(100% - 32px, var(--sg-page-width));
  margin-inline: auto;
}

.sg-skip {
  position: absolute;
  left: -999px;
  top: 10px;
  z-index: 110;
  background: var(--sg-accent);
  color: #1E1E1E;
  padding: 10px 18px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.9rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.sg-skip:focus {
  left: 8px;
}

.sg-header {
  position: sticky;
  top: 0;
  z-index: var(--sg-z-header);
  background: linear-gradient(180deg, #252525 0%, #1E1E1E 100%);
  border-bottom: 1px solid var(--sg-border);
  min-height: var(--sg-header-h);
}

.sg-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--sg-primary) 0%, var(--sg-accent) 100%);
  opacity: 0.85;
  z-index: 2;
}

.sg-header__progress {
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--sg-primary), var(--sg-accent));
  z-index: 3;
}

.sg-header__inner {
  width: min(100% - 32px, var(--sg-page-width));
  margin-inline: auto;
  min-height: var(--sg-header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.sg-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

.sg-brand__icon {
  position: relative;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: 1px solid rgba(212, 175, 55, 0.6);
  background: rgba(0, 168, 142, 0.1);
  flex-shrink: 0;
}

.sg-brand__icon::before {
  content: '';
  position: absolute;
  inset: 8px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.16);
}

.sg-brand__icon::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 10px;
  height: 10px;
  transform: translate(-50%, -50%) rotate(45deg);
  background: linear-gradient(135deg, var(--sg-accent) 0 50%, var(--sg-primary) 50% 100%);
  box-shadow: 0 0 10px rgba(212, 175, 55, 0.35);
}

.sg-brand__content {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.sg-brand__name {
  font-family: var(--sg-font-serif);
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--sg-text);
}

.sg-brand__tagline {
  font-family: var(--sg-font-mono);
  font-size: 0.7rem;
  letter-spacing: 1px;
  color: var(--sg-text-muted);
  margin-top: 2px;
}

.sg-nav-toggle {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  width: 44px;
  height: 44px;
  border-radius: 10px;
  border: 1px solid var(--sg-border);
  background: rgba(255, 255, 255, 0.03);
  transition: background 0.2s, border-color 0.2s;
}

.sg-nav-toggle:hover {
  background: rgba(0, 168, 142, 0.12);
  border-color: rgba(0, 168, 142, 0.4);
}

.sg-nav-toggle__bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--sg-text);
  border-radius: 2px;
  transition: transform 0.25s, opacity 0.25s;
}

.sg-nav-toggle[aria-expanded="true"] .sg-nav-toggle__bar:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.sg-nav-toggle[aria-expanded="true"] .sg-nav-toggle__bar:nth-child(2) {
  opacity: 0;
}

.sg-nav-toggle[aria-expanded="true"] .sg-nav-toggle__bar:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

.sg-nav {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  max-height: 0;
  overflow: hidden;
  visibility: hidden;
  opacity: 0;
  background: linear-gradient(180deg, #252525, #191919);
  border-bottom: 1px solid var(--sg-border);
  box-shadow: var(--sg-shadow);
  transition: max-height 0.3s, opacity 0.3s, visibility 0.3s;
}

.sg-nav[data-open] {
  max-height: calc(100vh - var(--sg-header-h));
  overflow-y: auto;
  visibility: visible;
  opacity: 1;
}

.sg-nav__list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0;
  padding: 12px;
}

.sg-nav__link {
  position: relative;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 16px;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--sg-text);
  border-bottom: 1px solid var(--sg-border);
  transition: background 0.2s, color 0.2s;
}

.sg-nav__link:hover {
  background: rgba(0, 168, 142, 0.12);
  color: #FFFFFF;
}

.sg-nav__index {
  font-family: var(--sg-font-mono);
  font-size: 0.72rem;
  color: var(--sg-accent);
  opacity: 0.85;
  min-width: 20px;
}

.sg-nav__label {
  white-space: nowrap;
}

.sg-nav__arrow {
  font-size: 0.85rem;
  opacity: 0.5;
  transition: opacity 0.2s, transform 0.2s;
}

.sg-nav__link:hover .sg-nav__arrow {
  opacity: 1;
  transform: translateX(3px);
}

.sg-nav__link[aria-current="page"] {
  color: var(--sg-accent);
}

.sg-nav__link[aria-current="page"]::after {
  content: '';
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: 2px;
  height: 1px;
  background: var(--sg-accent);
}

.sg-nav__item--member {
  margin-top: 0;
}

.sg-nav__link--member {
  margin-top: 12px;
  border: 1px solid var(--sg-gold-border);
  background: rgba(212, 175, 55, 0.08);
  color: var(--sg-accent);
  justify-content: center;
}

.sg-nav__link--member:hover {
  background: rgba(212, 175, 55, 0.16);
}

.sg-help {
  position: absolute;
  top: calc(100% + 10px);
  right: 16px;
  width: min(340px, calc(100vw - 32px));
  background: #242424;
  border: 1px solid var(--sg-border);
  border-radius: 14px;
  box-shadow: var(--sg-shadow);
  padding: 22px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: opacity 0.25s, transform 0.25s, visibility 0.25s;
  z-index: 50;
}

.sg-help[data-open] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.sg-help__inner {
  display: flex;
  flex-direction: column;
}

.sg-help__kicker {
  font-family: var(--sg-font-mono);
  font-size: 0.7rem;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--sg-primary-soft);
  margin-bottom: 6px;
}

.sg-help__title {
  font-family: var(--sg-font-serif);
  font-size: 1.2rem;
  color: var(--sg-text);
  margin-bottom: 14px;
}

.sg-help__list {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px 20px;
  margin-bottom: 16px;
}

.sg-help__list li {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: #BDBDBD;
}

.sg-help__list kbd {
  font-family: var(--sg-font-mono);
  font-size: 0.75rem;
  background: #111;
  color: var(--sg-accent);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 4px;
  padding: 2px 7px;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.1);
}

.sg-help__contact {
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--sg-text-muted);
  border-top: 1px solid var(--sg-border);
  padding-top: 14px;
}

.sg-footer {
  margin-top: 80px;
  background: #161616;
  border-top: 1px solid var(--sg-border);
  color: var(--sg-text);
}

.sg-footer::before {
  content: '';
  display: block;
  height: 3px;
  background: linear-gradient(90deg, var(--sg-primary) 0%, var(--sg-accent) 100%);
  opacity: 0.6;
}

.sg-footer__inner {
  width: min(100% - 32px, var(--sg-page-width));
  margin-inline: auto;
  padding: 56px 0 24px;
}

.sg-footer__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 40px;
}

.sg-footer__block--intro {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.sg-footer__name {
  font-family: var(--sg-font-serif);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--sg-text);
}

.sg-footer__tagline {
  font-family: var(--sg-font-mono);
  font-size: 0.72rem;
  letter-spacing: 1px;
  color: var(--sg-primary-soft);
  margin-top: 4px;
}

.sg-footer__desc {
  margin-top: 18px;
  color: var(--sg-text-muted);
  font-size: 0.9rem;
  line-height: 1.8;
  max-width: 36em;
}

.sg-footer__trust {
  margin-top: 16px;
  font-size: 0.78rem;
  line-height: 1.7;
  color: #7D7D7D;
  max-width: 36em;
  border-left: 2px solid rgba(0, 168, 142, 0.4);
  padding-left: 12px;
}

.sg-footer__title {
  font-family: var(--sg-font-serif);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 1px;
  color: var(--sg-accent);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--sg-border);
}

.sg-footer__list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.sg-footer__list a {
  color: var(--sg-text-muted);
  font-size: 0.9rem;
  transition: color 0.2s, padding-left 0.2s;
}

.sg-footer__list a:hover {
  color: var(--sg-primary-soft);
  padding-left: 4px;
}

.sg-footer__contact {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.sg-footer__contact-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.sg-footer__contact-label {
  font-family: var(--sg-font-mono);
  font-size: 0.7rem;
  letter-spacing: 1px;
  color: var(--sg-accent);
  text-transform: uppercase;
}

.sg-footer__contact-text {
  color: #BDBDBD;
  font-size: 0.9rem;
  line-height: 1.6;
}

.sg-footer__meta {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 48px;
  padding-top: 20px;
  border-top: 1px solid var(--sg-border);
  font-size: 0.8rem;
  color: var(--sg-text-muted);
}

.sg-footer__meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.sg-footer__divider {
  opacity: 0.5;
}

.sg-footer__meta-help {
  font-size: 0.76rem;
  color: #7D7D7D;
}

.sg-section {
  padding-block: 64px;
}

.sg-section--tight {
  padding-block: 36px;
}

.sg-section__mark {
  font-family: var(--sg-font-mono);
  font-size: 0.75rem;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--sg-accent);
}

.sg-section__title {
  font-family: var(--sg-font-serif);
  font-size: 2rem;
  line-height: 1.3;
  color: var(--sg-text);
  margin-top: 8px;
}

.sg-section__intro {
  color: var(--sg-text-muted);
  max-width: 42em;
  margin-top: 12px;
  font-size: 1rem;
}

.sg-card {
  background: var(--sg-bg-mid);
  border: 1px solid var(--sg-border);
  border-radius: var(--sg-radius);
  padding: 24px;
  transition: transform 0.25s, border-color 0.25s, box-shadow 0.25s;
}

.sg-card:hover {
  transform: translateY(-3px);
  border-color: rgba(0, 168, 142, 0.45);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.25);
}

.sg-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 12px 24px;
  border-radius: 999px;
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: 0.5px;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s, border-color 0.2s;
}

.sg-btn--primary {
  background: var(--sg-gradient);
  color: #FFFFFF;
  box-shadow: 0 8px 20px rgba(0, 168, 142, 0.25);
}

.sg-btn--primary:hover {
  background: linear-gradient(135deg, #00B89A 0%, var(--sg-accent) 100%);
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(0, 168, 142, 0.35);
}

.sg-btn--ghost {
  border: 1px solid var(--sg-gold-border);
  color: var(--sg-accent);
}

.sg-btn--ghost:hover {
  background: rgba(212, 175, 55, 0.1);
  transform: translateY(-2px);
}

.sg-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(0, 168, 142, 0.1);
  border: 1px solid rgba(0, 168, 142, 0.4);
  color: var(--sg-primary-soft);
  font-family: var(--sg-font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.5px;
  white-space: nowrap;
}

.sg-badge--gold {
  background: rgba(212, 175, 55, 0.1);
  border-color: var(--sg-gold-border);
  color: var(--sg-accent);
}

.sg-frame {
  position: relative;
  border: 1px solid rgba(212, 175, 55, 0.4);
  padding: 8px;
  background: rgba(0, 168, 142, 0.05);
}

.sg-frame::before {
  content: '';
  position: absolute;
  inset: 4px;
  border: 1px solid rgba(0, 168, 142, 0.35);
  pointer-events: none;
}

.sg-frame__content {
  position: relative;
  z-index: 1;
}

.sg-media {
  position: relative;
  display: block;
  border-radius: var(--sg-radius);
  overflow: hidden;
  background: linear-gradient(135deg, #2A2A2A, #1F1F1F);
  border: 1px solid var(--sg-border);
  aspect-ratio: 16 / 9;
}

.sg-media--portrait {
  aspect-ratio: 3 / 4;
}

.sg-media--square {
  aspect-ratio: 1 / 1;
}

.sg-media > img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.sg-media__label {
  position: absolute;
  left: 12px;
  bottom: 12px;
  z-index: 1;
  font-family: var(--sg-font-mono);
  font-size: 0.7rem;
  letter-spacing: 1px;
  color: #FFFFFF;
  background: rgba(0, 0, 0, 0.55);
  border-radius: 999px;
  padding: 4px 12px;
}

.sg-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 24px;
}

.sg-grid--split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.sg-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  font-family: var(--sg-font-mono);
  font-size: 0.8rem;
  color: var(--sg-text-muted);
}

.sg-breadcrumb a {
  color: var(--sg-primary-soft);
}

.sg-breadcrumb a:hover {
  color: var(--sg-primary);
}

[data-reveal] {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.4s var(--sg-delay, 0s), transform 0.4s var(--sg-delay, 0s);
}

[data-reveal][data-revealed] {
  opacity: 1;
  transform: none;
}

@media (min-width: 1025px) {
  .sg-nav-toggle {
    display: none;
  }

  .sg-nav {
    position: static;
    max-height: none;
    overflow: visible;
    visibility: visible;
    opacity: 1;
    background: none;
    border: 0;
    box-shadow: none;
    transition: none;
  }

  .sg-nav__list {
    flex-direction: row;
    align-items: center;
    gap: 2px;
    padding: 0;
  }

  .sg-nav__link {
    border-bottom: 0;
    padding: 10px 12px;
    font-size: 0.92rem;
  }

  .sg-nav__link[aria-current="page"]::after {
    left: 10px;
    right: 10px;
  }

  .sg-nav__link--member {
    margin-top: 0;
    margin-left: 8px;
    padding: 8px 16px;
    justify-content: flex-start;
  }
}

@media (max-width: 1023px) {
  .sg-footer__grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px 24px;
  }
}

@media (max-width: 767px) {
  .sg-footer__grid {
    grid-template-columns: 1fr;
  }

  .sg-grid--split {
    grid-template-columns: 1fr;
  }

  .sg-section {
    padding-block: 44px;
  }

  .sg-help {
    width: min(340px, calc(100vw - 24px));
    right: 12px;
  }
}

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

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

  .sg-nav,
  .sg-help,
  [data-reveal],
  .sg-card,
  .sg-btn {
    transition: none !important;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
  }
}