/* ==========================================================================
   球盟会娱乐数据档案 — 全站共享样式
   文件位置: /assets/site.css
   ========================================================================== */

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

html {
  line-height: 1.15;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body, h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd, ul, ol {
  margin: 0;
}

ul[class], ol[class] {
  list-style: none;
  padding: 0;
}

main {
  display: block;
}

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

input, button, textarea, select {
  font: inherit;
  color: inherit;
}

button {
  background: none;
  border: none;
  padding: 0;
}

/* ---------- Variables ---------- */
:root {
  --color-primary: #0b3d2e;
  --color-accent: #d4af37;
  --color-white: #f8f9f7;
  --color-dark: #1c2321;
  --color-light-green: #2a6b4f;
  --color-pale-gold: #f0d78c;
  --color-off-white: #e5e7e5;
  --color-muted-green: #162e24;
  --color-charcoal: #121715;

  --font-base: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-display: "Noto Sans SC", "DIN Alternate", "Helvetica Neue", sans-serif;
  --font-mono: "SF Mono", "Cascadia Code", "Consolas", monospace;

  --h1: 2.5rem;
  --h2: 1.75rem;
  --h3: 1.25rem;
  --body: 1rem;
  --caption: 0.875rem;

  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.5rem;
  --space-4: 2rem;
  --space-5: 3rem;
  --space-6: 4rem;

  --gutter: clamp(1rem, 4vw, 2.5rem);
  --content-max: 1200px;
  --transition: 300ms ease;
}

/* ---------- Base Typography ---------- */
body {
  font-family: var(--font-base);
  font-size: var(--body);
  line-height: 1.75;
  color: var(--color-white);
  background: var(--color-primary);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection {
  background: var(--color-accent);
  color: var(--color-charcoal);
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.2;
  color: inherit;
}

h1 { font-size: var(--h1); }
h2 { font-size: var(--h2); }
h3 { font-size: var(--h3); }

p {
  margin: 0 0 var(--space-2);
}

a {
  color: var(--color-pale-gold);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

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

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

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

#main-content {
  outline: none;
  scroll-margin-top: var(--space-2);
}

/* ---------- Accessibility ---------- */
.skip-link {
  position: fixed;
  left: var(--space-2);
  top: 0.75rem;
  z-index: 100;
  transform: translateY(-250%);
  background: var(--color-accent);
  color: var(--color-charcoal);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.875rem;
  padding: 0.625rem 1.25rem;
  border-radius: 0.25rem;
  text-decoration: none;
  transition: transform 200ms ease;
}

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

/* ---------- Header ---------- */
.site-header {
  position: relative;
  z-index: 50;
  background: var(--color-charcoal);
}

.header-topline {
  min-height: 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding: 0.25rem var(--gutter);
  background: var(--color-charcoal);
  border-bottom: 1px solid rgba(212, 175, 55, 0.22);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.header-topline__text {
  color: var(--color-pale-gold);
  margin: 0;
}

.header-topline__meta {
  color: rgba(229, 231, 229, 0.55);
  margin: 0;
}

.header-main {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 2.05fr) minmax(0, 3fr);
  align-items: stretch;
  min-height: 4.75rem;
  background: var(--color-charcoal);
}

.header-brand-block {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.2rem;
  padding: var(--space-2) var(--gutter);
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-muted-green) 100%);
  clip-path: polygon(0 0, calc(100% - 1.5rem) 0, 100% 100%, 0 100%);
}

.header-brand {
  display: inline-flex;
  flex-direction: column;
  gap: 0.1rem;
  width: fit-content;
  text-decoration: none;
}

.header-brand__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.375rem;
  line-height: 1.2;
  color: var(--color-white);
  letter-spacing: 0.02em;
}

.header-brand__sub {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-pale-gold);
}

.header-brand:hover .header-brand__name {
  color: var(--color-pale-gold);
}

.header-brand:hover .header-brand__sub {
  color: var(--color-accent);
}

.header-prefix {
  margin: 0.4rem 0 0;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  color: rgba(248, 249, 247, 0.6);
}

.header-prefix span {
  color: var(--color-accent);
}

.site-nav {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  padding: 0 var(--gutter);
  background: var(--color-primary);
  overflow: hidden;
}

.site-nav::before {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(115deg, transparent 0 22px, rgba(248, 249, 247, 0.03) 22px 23px);
  pointer-events: none;
}

.site-nav__list {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 0.125rem;
  counter-reset: nav-index;
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.625rem;
  font-family: var(--font-display);
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-white);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: color var(--transition), border-color var(--transition), background var(--transition);
}

.site-nav__link::before {
  counter-increment: nav-index;
  content: "0" counter(nav-index);
  font-family: var(--font-mono);
  font-size: 0.625rem;
  color: var(--color-accent);
  opacity: 0.8;
  letter-spacing: 0.04em;
}

.site-nav__link:hover {
  color: var(--color-pale-gold);
  border-bottom-color: var(--color-accent);
}

.site-nav__link[aria-current="page"] {
  color: var(--color-pale-gold);
  border-bottom-color: var(--color-accent);
  background: rgba(212, 175, 55, 0.08);
}

.nav-toggle {
  display: none;
  position: absolute;
  top: 50%;
  right: var(--gutter);
  transform: translateY(-50%);
  z-index: 4;
  align-items: center;
  gap: 0.625rem;
  background: var(--color-charcoal);
  color: var(--color-white);
  border: 1px solid rgba(212, 175, 55, 0.45);
  border-radius: 999px;
  padding: 0.5rem 0.875rem 0.5rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: border-color var(--transition), color var(--transition);
}

.nav-toggle:hover {
  border-color: var(--color-accent);
  color: var(--color-pale-gold);
}

.nav-toggle__label {
  line-height: 1;
}

.nav-toggle__line {
  position: relative;
  display: inline-block;
  width: 18px;
  height: 2px;
  background: currentColor;
}

.nav-toggle__line::before,
.nav-toggle__line::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: currentColor;
  transition: transform var(--transition), top var(--transition);
}

.nav-toggle__line::before {
  top: -6px;
}

.nav-toggle__line::after {
  top: 6px;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line {
  background: transparent;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line::before {
  top: 0;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line::after {
  top: 0;
  transform: rotate(-45deg);
}

.header-float {
  position: fixed;
  right: var(--gutter);
  bottom: var(--gutter);
  z-index: 60;
}

.version-copy {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  background: var(--color-accent);
  color: var(--color-charcoal);
  border: none;
  border-radius: 999px;
  padding: 0.625rem 1.125rem 0.625rem 1.375rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  box-shadow: 0 10px 30px rgba(18, 23, 21, 0.5);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
}

.version-copy:hover {
  background: var(--color-pale-gold);
  transform: translateY(-2px);
  box-shadow: 0 14px 34px rgba(18, 23, 21, 0.55);
}

.version-copy--copied {
  background: var(--color-light-green);
  color: var(--color-white);
}

.version-copy--copied .version-copy__code {
  color: rgba(248, 249, 247, 0.7);
}

.version-copy__code {
  text-transform: uppercase;
  letter-spacing: 0.12em;
  opacity: 0.7;
}

.version-copy__value {
  font-weight: 800;
  font-variant-numeric: tabular-nums;
}

/* ---------- Footer ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  background: var(--color-charcoal);
  color: var(--color-off-white);
  border-top: 3px solid var(--color-accent);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: repeating-linear-gradient(115deg, transparent 0 24px, rgba(212, 175, 55, 0.03) 24px 25px);
  pointer-events: none;
}

.footer-architecture {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 2.2fr) repeat(3, minmax(0, 1fr));
  gap: var(--space-5) var(--space-4);
  padding: var(--space-6) var(--gutter) var(--space-5);
}

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

.footer-architecture::after {
  content: "023";
  position: absolute;
  right: -0.5rem;
  bottom: -3rem;
  z-index: 0;
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 12rem;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px rgba(212, 175, 55, 0.12);
  pointer-events: none;
  user-select: none;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-brand__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.375rem;
  color: var(--color-white);
}

.footer-brand__desc {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-pale-gold);
  margin: 0;
}

.footer-brand__stamp {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  margin-top: 0.75rem;
  padding: 0.3rem 0.6rem;
  border: 1px solid rgba(212, 175, 55, 0.3);
  border-radius: 0.25rem;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(229, 231, 229, 0.55);
}

.footer-column {
  display: flex;
  flex-direction: column;
  gap: 0.875rem;
}

.footer-column__title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.footer-column__list {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-column__list a {
  font-size: 0.875rem;
  color: rgba(248, 249, 247, 0.75);
  text-decoration: none;
  transition: color var(--transition), padding-left var(--transition);
}

.footer-column__list a:hover {
  color: var(--color-pale-gold);
  padding-left: 0.25rem;
}

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
  margin-top: 1.25rem;
}

.footer-contact__line {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: rgba(229, 231, 229, 0.6);
}

.footer-statement {
  position: relative;
  z-index: 1;
  max-width: 90ch;
  padding: var(--space-2) var(--gutter);
  border-top: 1px solid rgba(248, 249, 247, 0.08);
  font-size: 0.78125rem;
  color: rgba(229, 231, 229, 0.55);
}

.footer-bottom {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem 1.5rem;
  padding: 1.25rem var(--gutter);
  border-top: 1px solid rgba(248, 249, 247, 0.06);
  background: var(--color-muted-green);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.06em;
  color: rgba(229, 231, 229, 0.65);
}

.footer-bottom p {
  margin: 0;
}

.footer-bottom__year {
  margin-left: auto;
  color: var(--color-pale-gold);
}

/* ---------- Layout Primitives ---------- */
.page-container {
  width: min(var(--content-max), calc(100% - var(--gutter) - var(--gutter)));
  margin-inline: auto;
}

.section {
  padding-block: var(--space-6);
}

.section--tight {
  padding-block: var(--space-4);
}

.section--dark {
  background: var(--color-charcoal);
  color: var(--color-white);
}

.section--muted {
  background: var(--color-muted-green);
  color: var(--color-off-white);
}

.section--tint {
  background: var(--color-light-green);
  color: var(--color-white);
}

.section--light {
  background: var(--color-off-white);
  color: var(--color-dark);
}

.section--light a {
  color: #7d6115;
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.5rem 1rem;
  margin-bottom: var(--space-4);
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--color-muted-green);
}

.section-index {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.section-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: var(--h2);
  font-weight: 800;
  line-height: 1.25;
}

.section-desc {
  max-width: 62ch;
  font-size: var(--caption);
  color: rgba(248, 249, 247, 0.7);
}

.section--light .section-desc {
  color: rgba(18, 23, 21, 0.7);
}

.grid {
  display: grid;
  gap: var(--space-4);
}

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

.grid--3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid--aside {
  grid-template-columns: minmax(0, 2.4fr) minmax(0, 1fr);
  gap: var(--space-5);
}

.grid--split {
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: var(--space-5);
}

/* ---------- Breadcrumb ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 var(--space-4);
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-off-white);
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumb li:not(:last-child)::after {
  content: "/";
  color: var(--color-accent);
}

.breadcrumb a {
  color: var(--color-pale-gold);
  text-decoration: none;
}

.breadcrumb a:hover {
  color: var(--color-accent);
  text-decoration: underline;
}

.breadcrumb [aria-current="page"] {
  color: var(--color-off-white);
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.375rem;
  border-radius: 0.25rem;
  border: 1px solid transparent;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.9375rem;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition), transform var(--transition);
}

.btn--gold {
  background: var(--color-accent);
  color: var(--color-charcoal);
}

.btn--gold:hover {
  background: var(--color-pale-gold);
  color: var(--color-dark);
}

.btn--ghost {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: transparent;
}

.btn--ghost:hover {
  background: rgba(212, 175, 55, 0.12);
  color: var(--color-pale-gold);
}

.btn--dark {
  background: var(--color-muted-green);
  color: var(--color-white);
  border-color: rgba(212, 175, 55, 0.2);
}

.btn--dark:hover {
  border-color: var(--color-accent);
}

/* ---------- Media Frame ---------- */
.media-frame {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  border-radius: 0.375rem;
  background:
    radial-gradient(ellipse at 75% 20%, rgba(212, 175, 55, 0.14), transparent 55%),
    linear-gradient(145deg, var(--color-muted-green), var(--color-dark));
}

.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(rgba(248, 249, 247, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(248, 249, 247, 0.05) 1px, transparent 1px);
  background-size: 26px 26px;
  -webkit-mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.8), rgba(0, 0, 0, 0.3));
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.8), rgba(0, 0, 0, 0.3));
}

.media-frame::after {
  content: "";
  position: absolute;
  left: -20%;
  right: -20%;
  bottom: -45%;
  height: 60%;
  background: linear-gradient(165deg, transparent 45%, rgba(212, 175, 55, 0.18) 50%, transparent 55%);
  transform: rotate(-3deg);
  pointer-events: none;
}

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

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

.media-frame__tag {
  position: absolute;
  left: 0.75rem;
  top: 0.75rem;
  z-index: 1;
}

.media-frame__caption {
  position: absolute;
  left: 0.75rem;
  right: 0.75rem;
  bottom: 0.75rem;
  z-index: 1;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  color: var(--color-pale-gold);
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.6);
}

/* ---------- Data Visual Elements ---------- */
.big-number {
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: clamp(3rem, 9vw, 5.5rem);
  line-height: 0.95;
  letter-spacing: -0.03em;
  color: var(--color-accent);
  font-variant-numeric: tabular-nums;
}

.big-number__unit {
  margin-left: 0.35rem;
  font-size: 0.35em;
  font-weight: 600;
  color: var(--color-off-white);
}

.version-code {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1.25rem;
  background: var(--color-charcoal);
  border: 1px solid rgba(212, 175, 55, 0.4);
  border-radius: 0.25rem;
  font-family: var(--font-mono);
}

.version-code__label {
  font-size: 0.625rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(229, 231, 229, 0.55);
}

.version-code__value {
  font-size: 1.0625rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--color-pale-gold);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
  border: 1px solid rgba(212, 175, 55, 0.35);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-pale-gold);
  white-space: nowrap;
}

.data-rule {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-block: var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--color-off-white);
}

.data-rule::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, rgba(212, 175, 55, 0.45), transparent);
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.75rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.legend__item {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.78125rem;
  color: var(--color-off-white);
}

.legend__dot {
  width: 0.625rem;
  height: 0.625rem;
  border-radius: 50%;
  background: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(212, 175, 55, 0.15);
}

.legend__dot--green {
  background: var(--color-light-green);
  box-shadow: 0 0 0 3px rgba(42, 107, 79, 0.2);
}

.legend__dot--gray {
  background: var(--color-dark);
  box-shadow: 0 0 0 3px rgba(28, 35, 33, 0.3);
}

/* ---------- Alert Note ---------- */
.alert-note {
  margin-block: var(--space-4);
  padding: var(--space-2) 1.375rem;
  border-left: 3px solid var(--color-accent);
  background: var(--color-muted-green);
  border-radius: 0 0.375rem 0.375rem 0;
  font-size: var(--caption);
  color: var(--color-off-white);
}

.alert-note strong {
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--color-pale-gold);
}

/* ---------- Tabs ---------- */
.tabs__list {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  margin: 0 0 var(--space-4);
  padding: 0 0 0;
  border-bottom: 1px solid var(--color-muted-green);
  list-style: none;
}

.tabs__button {
  appearance: none;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 -1px;
  padding: 0.625rem 1rem 0.5rem;
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--color-off-white);
  cursor: pointer;
  transition: color var(--transition), border-color var(--transition), background var(--transition);
}

.tabs__button::before {
  content: "▹";
  color: var(--color-accent);
  font-size: 0.75rem;
}

.tabs__button:hover {
  color: var(--color-pale-gold);
  background: rgba(212, 175, 55, 0.06);
}

.tabs__button[aria-selected="true"] {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
  background: rgba(212, 175, 55, 0.1);
}

.tabs__panel {
  display: none;
  padding-block: var(--space-4);
}

.tabs__panel[data-active] {
  display: block;
  animation: tab-in 300ms ease both;
}

@keyframes tab-in {
  from {
    opacity: 0;
    transform: translateX(20px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

/* ---------- Reveal ---------- */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 500ms ease, transform 500ms ease;
}

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

/* ---------- Motion & Decoration ---------- */
@media (prefers-reduced-motion: no-preference) {
  .site-nav::before {
    animation: stream-drift-nav 28s linear infinite;
  }

  .site-footer::before {
    animation: stream-drift-footer 42s linear infinite;
  }
}

@keyframes stream-drift-nav {
  from { background-position-x: 0; }
  to { background-position-x: 23px; }
}

@keyframes stream-drift-footer {
  from { background-position-x: 0; }
  to { background-position-x: 25px; }
}

@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;
  }

  html.js [data-reveal],
  [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .tabs__panel[data-active] {
    animation: none;
  }
}

/* ---------- Responsive ---------- */
@media (max-width: 1099px) {
  .footer-architecture {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-brand {
    grid-column: span 2;
  }

  .footer-architecture::after {
    font-size: 8rem;
    bottom: -1.5rem;
  }

  .footer-contact {
    margin-top: 0.5rem;
  }
}

@media (max-width: 899px) {
  .header-main {
    grid-template-columns: minmax(0, 1fr);
    min-height: auto;
  }

  .header-brand-block {
    clip-path: none;
    border-bottom: 1px solid rgba(212, 175, 55, 0.2);
  }

  .site-nav {
    display: none;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    padding: 0;
    overflow: visible;
  }

  .site-nav[data-open] {
    display: flex;
  }

  .site-nav__list {
    flex-direction: column;
    gap: 0;
    padding: 0.5rem 0;
  }

  .site-nav__link {
    justify-content: flex-start;
    width: 100%;
    padding: 0.875rem var(--gutter);
    border-bottom: 1px solid rgba(248, 249, 247, 0.08);
    border-radius: 0;
  }

  .site-nav__link[aria-current="page"] {
    background: rgba(212, 175, 55, 0.12);
    border-left: 3px solid var(--color-accent);
    border-bottom-color: rgba(248, 249, 247, 0.08);
    border-radius: 0;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .grid--2,
  .grid--3,
  .grid--split {
    grid-template-columns: minmax(0, 1fr);
  }

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

@media (max-width: 767px) {
  .header-topline__meta {
    display: none;
  }

  .header-topline {
    justify-content: center;
  }

  .footer-architecture {
    grid-template-columns: minmax(0, 1fr);
    gap: var(--space-4);
    padding-top: var(--space-5);
  }

  .footer-brand {
    grid-column: auto;
  }

  .footer-architecture::after {
    font-size: 6rem;
    bottom: -1rem;
    right: 0;
  }

  .footer-bottom__year {
    margin-left: 0;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .version-copy {
    padding: 0.5rem 0.875rem 0.5rem 1rem;
    font-size: 0.6875rem;
  }

  .version-copy__code {
    display: none;
  }
}