/* =========================================================
   63棋牌竞技 · Shared Site Kit
   长云轨道 — 高原蓝 / 雪山白 / 草原绿 / 金色能量
   ========================================================= */

/* ---- 1. Reset & Design Tokens ---- */
:root {
  --c-dark: #0B0F1A;
  --c-ink: #1A1F2E;
  --c-white: #F7F5F0;
  --c-mist: #E9E4D8;
  --c-gold: #C9A44C;
  --c-blue: #3A7CA5;
  --c-green: #5B8C5A;
  --c-cloud: #B8B8A8;
  --c-body-text: #2A3340;
  --c-body-muted: #6B7280;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --header-width: 280px;
  --header-height: 64px;
  --container-max: 1360px;
  --radius-sm: 2px;
  --radius-md: 6px;
  --radius-lg: 14px;
  --shadow-sm: 0 1px 2px rgba(11, 15, 26, 0.06);
  --shadow-md: 0 8px 24px rgba(11, 15, 26, 0.08);
  --border-cloud: 1px solid var(--c-cloud);
  --ease: 0.25s ease;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-weight: 400;
  line-height: 1.75;
  color: var(--c-body-text);
  background-color: var(--c-white);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--c-blue);
  text-decoration: none;
  transition: color var(--ease);
}

a:hover {
  color: var(--c-gold);
}

ul, ol {
  list-style: none;
}

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

::selection {
  background: rgba(201, 164, 76, 0.35);
  color: var(--c-dark);
}

:focus-visible {
  outline: 2px solid var(--c-gold);
  outline-offset: 3px;
}

/* ---- 2. Base Typography ---- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  font-weight: 900;
  line-height: 1.2;
  color: var(--c-dark);
}

.lead {
  font-size: 1.125rem;
  line-height: 1.75;
  color: var(--c-body-muted);
}

.serif-em {
  font-family: var(--font-serif);
  font-weight: 600;
  color: var(--c-gold);
}

/* ---- 3. Layout Primitives ---- */
#main-content {
  display: block;
  min-height: 70vh;
  background-color: var(--c-white);
}

#main-content:focus {
  outline: none;
}

.site-container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: clamp(1.25rem, 4vw, 3rem);
}

.section {
  padding: clamp(2rem, 5vw, 4.5rem) 0;
}

.section__heading {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  font-size: clamp(1.375rem, 3vw, 2.125rem);
  margin-bottom: 1rem;
}

.section__heading::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--c-gold), transparent);
}

.section__lead {
  max-width: 42rem;
  color: var(--c-body-muted);
  margin-bottom: 1.75rem;
}

/* ---- 4. Breadcrumb ---- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  padding: 1.25rem 0;
  font-size: 0.875rem;
  color: var(--c-cloud);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumb__item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumb__item + .breadcrumb__item::before {
  content: "∕";
  color: var(--c-cloud);
}

.breadcrumb__link {
  color: var(--c-blue);
}

.breadcrumb__current {
  color: var(--c-dark);
  font-weight: 600;
}

/* ---- 5. Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.5rem;
  font-size: 0.9375rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: background var(--ease), color var(--ease), border-color var(--ease), transform 0.15s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn--primary {
  background: var(--c-gold);
  color: var(--c-dark);
  border-color: var(--c-gold);
}

.btn--primary:hover {
  background: #b8933f;
  border-color: #b8933f;
  color: var(--c-dark);
}

.btn--ghost {
  background: transparent;
  color: var(--c-dark);
  border-color: var(--c-cloud);
}

.btn--ghost:hover {
  border-color: var(--c-gold);
  color: var(--c-gold);
}

.btn--light {
  background: transparent;
  color: var(--c-white);
  border-color: rgba(247, 245, 240, 0.35);
}

.btn--light:hover {
  border-color: var(--c-gold);
  color: var(--c-gold);
}

/* ---- 6. Cards & Tags ---- */
.card {
  background: var(--c-white);
  border: var(--border-cloud);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  padding: 1.5rem;
  transition: box-shadow var(--ease), border-color var(--ease);
}

.card:hover {
  border-color: rgba(201, 164, 76, 0.4);
  box-shadow: var(--shadow-md);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.25rem 0.75rem;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  border-radius: 999px;
  border: 1px solid transparent;
  white-space: nowrap;
}

.tag--gold {
  background: rgba(201, 164, 76, 0.14);
  color: #8a6e2a;
  border-color: rgba(201, 164, 76, 0.32);
}

.tag--green {
  background: rgba(91, 140, 90, 0.14);
  color: #3e6540;
  border-color: rgba(91, 140, 90, 0.32);
}

.tag--blue {
  background: rgba(58, 124, 165, 0.12);
  color: #2b5e7d;
  border-color: rgba(58, 124, 165, 0.3);
}

.badge {
  display: inline-block;
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--c-green);
  box-shadow: 0 0 0 3px rgba(91, 140, 90, 0.18);
}

/* ---- 7. Image Containers ---- */
.image-frame {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-md);
  border: 1px solid rgba(184, 184, 168, 0.25);
  background: var(--c-mist);
  aspect-ratio: 16 / 10;
}

.image-frame img,
.image-frame svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.image-frame--wide {
  aspect-ratio: 21 / 9;
}

.image-frame--tall {
  aspect-ratio: 4 / 5;
}

.image-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  color: var(--c-cloud);
  font-size: 0.875rem;
  letter-spacing: 0.08em;
  background:
    linear-gradient(135deg, rgba(11, 15, 26, 0.04) 25%, transparent 25%) 0 0 / 14px 14px,
    linear-gradient(315deg, rgba(11, 15, 26, 0.04) 25%, transparent 25%) 0 0 / 14px 14px,
    var(--c-mist);
}

/* ---- 8. Grid ---- */
.grid {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .grid--2 {
    grid-template-columns: repeat(2, 1fr);
  }
  .grid--3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 960px) {
  .grid--4 {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ---- 9. Skip Link ---- */
.skip-link {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 1000;
  padding: 0.75rem 1.5rem;
  background: var(--c-gold);
  color: var(--c-dark);
  font-weight: 700;
  font-size: 0.875rem;
  transform: translateY(-200%);
  transition: transform 0.2s ease;
}

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

/* ---- 10. Scroll Progress ---- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  z-index: 300;
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--c-blue), var(--c-gold));
}

/* ---- 11. Header ---- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: 100;
  background:
    radial-gradient(rgba(201, 164, 76, 0.07) 1px, transparent 1px) 0 0 / 14px 14px,
    var(--c-dark);
  border-bottom: 1px solid rgba(201, 164, 76, 0.25);
  color: var(--c-white);
}

.site-header__inner {
  display: flex;
  align-items: center;
  height: 100%;
  padding: 0 1rem;
  position: relative;
}

.site-brand {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  color: var(--c-white);
  min-width: 0;
}

.site-brand:hover {
  color: var(--c-gold);
}

.site-brand__mark {
  width: 2.25rem;
  height: 2.25rem;
  flex-shrink: 0;
  color: var(--c-gold);
}

.site-brand__svg {
  width: 100%;
  height: 100%;
}

.site-brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.site-brand__title {
  font-size: 1.125rem;
  font-weight: 900;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.site-brand__subtitle {
  font-size: 0.6875rem;
  color: var(--c-cloud);
  letter-spacing: 0.08em;
  white-space: nowrap;
}

.site-nav-toggle {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 2.5rem;
  height: 2.5rem;
  margin-left: auto;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(247, 245, 240, 0.15);
  background: transparent;
  color: var(--c-white);
  transition: border-color var(--ease), background var(--ease);
}

.site-nav-toggle:hover {
  border-color: var(--c-gold);
  background: rgba(201, 164, 76, 0.1);
}

.site-nav-toggle[aria-expanded="true"] {
  border-color: var(--c-gold);
}

.site-nav-toggle__line {
  display: block;
  width: 1.25rem;
  height: 2px;
  background: currentColor;
  border-radius: 1px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.site-nav-toggle[aria-expanded="true"] .site-nav-toggle__line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

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

.site-nav-toggle[aria-expanded="true"] .site-nav-toggle__line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.site-nav {
  position: fixed;
  top: var(--header-height);
  left: 0;
  right: 0;
  max-height: calc(100vh - var(--header-height));
  overflow-y: auto;
  background: var(--c-ink);
  border-bottom: 1px solid rgba(201, 164, 76, 0.2);
  box-shadow: 0 12px 32px rgba(11, 15, 26, 0.35);
  transform: translateY(-120%);
  opacity: 0;
  visibility: hidden;
  transition: transform 0.3s ease, opacity 0.3s ease, visibility 0.3s;
}

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

.site-nav__list {
  display: flex;
  flex-direction: column;
  padding: 0.5rem;
}

.site-nav__link {
  display: block;
  padding: 0.875rem 1rem;
  color: var(--c-cloud);
  font-size: 0.9375rem;
  letter-spacing: 0.05em;
  border-left: 2px solid transparent;
  transition: color 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.site-nav__link:hover {
  color: var(--c-white);
  background: rgba(201, 164, 76, 0.08);
  border-left-color: var(--c-gold);
}

.site-nav__link[aria-current="page"] {
  color: var(--c-gold);
  background: rgba(201, 164, 76, 0.1);
  border-left-color: var(--c-gold);
  font-weight: 700;
}

.site-header__meta {
  display: none;
}

/* ---- 12. Back to Top ---- */
.to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 999px;
  background: var(--c-dark);
  color: var(--c-white);
  border: 1px solid rgba(201, 164, 76, 0.45);
  box-shadow: 0 4px 16px rgba(11, 15, 26, 0.2);
  transition: background var(--ease), color var(--ease), border-color var(--ease), transform var(--ease);
}

.to-top:hover {
  background: var(--c-gold);
  color: var(--c-dark);
  border-color: var(--c-gold);
  transform: translateY(-2px);
}

.to-top[hidden] {
  display: none;
}

.to-top__icon {
  width: 1.25rem;
  height: 1.25rem;
}

/* ---- 13. Footer ---- */
.site-footer {
  position: relative;
  margin-top: 4rem;
  background:
    radial-gradient(rgba(201, 164, 76, 0.05) 1px, transparent 1px) 0 0 / 22px 22px,
    var(--c-dark);
  color: rgba(247, 245, 240, 0.65);
}

.site-footer::before {
  content: "";
  display: block;
  height: 3px;
  background: linear-gradient(90deg, var(--c-blue), var(--c-green) 38%, var(--c-gold) 78%);
}

.site-footer__inner {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: clamp(1.75rem, 4vw, 3.25rem) clamp(1.25rem, 4vw, 3rem) 1.5rem;
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.75rem;
}

.site-footer__brand-title {
  font-size: 1.375rem;
  font-weight: 900;
  color: var(--c-white);
  letter-spacing: 0.04em;
  margin-bottom: 0.75rem;
}

.site-footer__brand-desc {
  font-size: 0.875rem;
  line-height: 1.7;
  color: rgba(247, 245, 240, 0.6);
  margin-bottom: 1rem;
  max-width: 28rem;
}

.site-footer__brand-trust {
  font-size: 0.8125rem;
  color: var(--c-gold);
  padding-left: 0.875rem;
  border-left: 2px solid var(--c-gold);
  line-height: 1.5;
}

.site-footer__heading {
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--c-white);
  margin-bottom: 1rem;
  letter-spacing: 0.06em;
}

.site-footer__links {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.site-footer__link {
  color: rgba(247, 245, 240, 0.65);
  font-size: 0.875rem;
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.site-footer__link:hover {
  color: var(--c-gold);
  padding-left: 0.25rem;
}

.site-footer__contact-item {
  font-size: 0.875rem;
  color: rgba(247, 245, 240, 0.65);
  line-height: 1.7;
}

.site-footer__contact-item + .site-footer__contact-item {
  margin-top: 0.375rem;
}

.site-footer__contact-label {
  display: inline-block;
  min-width: 2.2em;
  color: var(--c-cloud);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
}

.site-footer__bottom {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  margin-top: 2.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid rgba(247, 245, 240, 0.08);
  font-size: 0.8125rem;
  color: rgba(247, 245, 240, 0.45);
  text-align: center;
}

.site-footer__icp {
  color: rgba(247, 245, 240, 0.45);
  transition: color var(--ease);
}

.site-footer__icp:hover {
  color: var(--c-gold);
}

/* ---- 14. Scroll Reveal ---- */
@media (prefers-reduced-motion: no-preference) {
  [data-reveal] {
    opacity: 0;
    transform: translateY(18px);
    transition: opacity 0.55s ease, transform 0.55s ease;
  }

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

/* ---- 15. Tablet & Desktop ---- */
@media (min-width: 640px) {
  .site-footer__grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .site-footer__brand {
    grid-column: 1 / -1;
  }

  .site-footer__bottom {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }

  .to-top {
    right: 1.75rem;
    bottom: 1.75rem;
  }
}

@media (min-width: 960px) {
  body {
    padding-left: var(--header-width);
  }

  .to-top {
    right: 2rem;
    bottom: 2rem;
  }

  .scroll-progress {
    left: var(--header-width);
    width: calc(100% - var(--header-width));
  }

  .site-header {
    top: 0;
    left: 0;
    right: auto;
    bottom: 0;
    width: var(--header-width);
    height: 100vh;
    border-right: 1px solid rgba(201, 164, 76, 0.2);
    border-bottom: none;
  }

  .site-header::before {
    content: "";
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    width: 3px;
    background: linear-gradient(to bottom, var(--c-gold) 0%, var(--c-blue) 46%, var(--c-green) 100%);
  }

  .site-header__inner {
    flex-direction: column;
    align-items: stretch;
    padding: 2.25rem 1.75rem 1.5rem;
    gap: 2.25rem;
  }

  .site-brand__mark {
    width: 3rem;
    height: 3rem;
  }

  .site-brand__title {
    font-size: 1.375rem;
  }

  .site-nav-toggle {
    display: none;
  }

  .site-nav {
    position: static;
    max-height: none;
    overflow-y: visible;
    background: transparent;
    border-bottom: none;
    box-shadow: none;
    transform: none;
    opacity: 1;
    visibility: visible;
  }

  .site-nav[data-open] {
    transform: none;
    opacity: 1;
    visibility: visible;
  }

  .site-nav__list {
    flex-direction: column;
    gap: 0.125rem;
    padding: 0;
  }

  .site-nav__link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.6875rem 0.75rem 0.6875rem 0.875rem;
    border-left: none;
  }

  .site-nav__link::before {
    content: "";
    flex-shrink: 0;
    width: 6px;
    height: 6px;
    transform: rotate(45deg);
    border: 1px solid var(--c-gold);
    background: transparent;
    transition: background 0.2s ease, transform 0.2s ease;
  }

  .site-nav__link:hover::before,
  .site-nav__link[aria-current="page"]::before {
    background: var(--c-gold);
    transform: rotate(45deg) scale(1.15);
  }

  .site-nav__link:hover {
    background: none;
    padding-left: 0.875rem;
  }

  .site-nav__link[aria-current="page"] {
    background: none;
  }

  .site-header__meta {
    display: flex;
    flex-direction: column;
    gap: 0.375rem;
    margin-top: auto;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(247, 245, 240, 0.08);
  }

  .site-header__trust {
    font-size: 0.8125rem;
    line-height: 1.5;
    color: var(--c-cloud);
  }

  .site-header__contact {
    font-family: var(--font-serif);
    font-weight: 600;
    font-size: 1.125rem;
    color: var(--c-gold);
    letter-spacing: 0.02em;
  }

  .site-header__contact:hover {
    color: var(--c-white);
  }

  .site-footer {
    margin-top: 5rem;
  }

  .site-footer__grid {
    grid-template-columns: 2fr 1fr 1fr 1.25fr;
    gap: 2.5rem;
  }

  .site-footer__brand {
    grid-column: auto;
  }

  .site-footer__inner {
    padding-top: clamp(2.25rem, 4vw, 3.75rem);
  }

  section[id],
  div[id] {
    scroll-margin-top: 2rem;
  }
}

/* ---- 16. Reduced Motion ---- */
@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;
  }
}