/* ============ 基础与变量 ============ */
:root {
  --color-bg: #0B0C10;
  --color-bg-card: #1F2228;
  --color-bg-footer: #16171D;
  --color-text: #F5F0EB;
  --color-text-dim: rgba(245, 240, 235, 0.72);
  --color-text-faint: rgba(245, 240, 235, 0.5);
  --color-border: rgba(245, 240, 235, 0.13);
  --color-border-strong: rgba(245, 240, 235, 0.26);
  --color-red: #FF3B30;
  --color-yellow: #FFD600;
  --color-blue: #00E5FF;
  --color-green: #7A8B5A;
  --color-cite: #C67B5C;
  --color-alert: #FF6B00;
  --font-head: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Source Sans 3", "Helvetica Neue", Arial, system-ui, sans-serif;
  --font-mono: "Roboto Mono", "SFMono-Regular", Menlo, Consolas, monospace;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4.5rem;
  --header-z: 1000;
}

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

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

ul,
ol {
  margin: 0;
  padding-left: 1.25rem;
}

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

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

main {
  display: block;
  flex: 1;
  width: 100%;
}

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

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

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

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

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: 0.01em;
}

h1 {
  font-size: clamp(1.9rem, 4vw, 3.5rem);
}

h2 {
  font-size: clamp(1.4rem, 3vw, 2.25rem);
}

h3 {
  font-size: 1.125rem;
}

::selection {
  background: var(--color-red);
  color: #fff;
}

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

/* ============ 通用工具 ============ */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: -999px;
  z-index: 2000;
  background: var(--color-red);
  color: #fff;
  padding: 0.7rem 1.1rem;
  font-family: var(--font-head);
  font-weight: 700;
  clip-path: polygon(0 0, calc(100% - 10px) 0, 100% 100%, 10px 100%);
}

.skip-link:focus-visible {
  left: 1rem;
  outline-color: var(--color-yellow);
}

.site-container {
  width: min(var(--container), calc(100% - 2rem));
  margin-inline: auto;
  --container: 1200px;
}

.divider {
  height: 1px;
  margin: var(--space-7) 0;
  border: 0;
  background: linear-gradient(90deg, var(--color-border), transparent);
}

/* ============ 页头 ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--header-z);
  padding-top: 3px;
  background:
    linear-gradient(rgba(255, 255, 255, 0.018) 1px, transparent 1px) 0 0 / 36px 36px,
    linear-gradient(90deg, rgba(255, 255, 255, 0.018) 1px, transparent 1px) 0 0 / 36px 36px,
    var(--color-bg);
  border-bottom: 1px solid var(--color-border);
}

.site-progress {
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  z-index: 2;
  background: linear-gradient(90deg, var(--color-red), var(--color-yellow), var(--color-blue));
  transition: width 80ms linear;
}

.site-header__meta {
  border-bottom: 1px solid var(--color-border);
  background: rgba(22, 23, 29, 0.86);
}

.site-header__meta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  min-height: 2.5rem;
}

.site-header__status {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  color: var(--color-text-dim);
}

.status-dot {
  position: relative;
  width: 0.5rem;
  height: 0.5rem;
  flex: none;
  background: var(--color-green);
  animation: pulse 2.2s ease-out infinite;
}

@keyframes pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(122, 139, 90, 0.6);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(122, 139, 90, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(122, 139, 90, 0);
  }
}

.nav-upper {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-upper__link {
  display: inline-block;
  padding: 0.4rem 0.9rem;
  color: var(--color-text-dim);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  transition: color 0.2s;
}

.nav-upper__link::before {
  content: "";
  display: inline-block;
  width: 3px;
  height: 8px;
  margin-right: 0.4rem;
  background: var(--color-red);
  transform: skewX(-18deg);
}

.nav-upper__link:hover,
.nav-upper__link[aria-current="page"] {
  color: var(--color-blue);
}

.site-header__main {
  position: relative;
}

.site-header__main::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: min(34vw, 26rem);
  height: 2px;
  background: linear-gradient(90deg, var(--color-red), var(--color-yellow) 70%, transparent);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.site-header__main-inner {
  display: flex;
  align-items: center;
  gap: 2rem;
  min-height: 4.5rem;
}

.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--color-text);
}

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

.site-brand__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  flex: none;
  background: var(--color-red);
  color: #fff;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.15rem;
  line-height: 1;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%);
}

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

.site-brand__name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.3rem;
  letter-spacing: 0.08em;
}

.site-brand__tagline {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-yellow);
}

.nav-lower {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  margin-left: auto;
}

.nav-lower__link {
  position: relative;
  display: inline-block;
  padding: 0.6rem 1rem;
  color: var(--color-text);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.08em;
  transition: color 0.2s;
}

.nav-lower__link::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 0.25rem;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--color-red), var(--color-yellow));
  transform: translateX(-50%);
  transition: width 0.3s ease;
}

.nav-lower__link:hover,
.nav-lower__link[aria-current="page"] {
  color: var(--color-yellow);
}

.nav-lower__link:hover::after,
.nav-lower__link[aria-current="page"]::after {
  width: 60%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0.5rem;
  border: 1px solid var(--color-border);
  background: transparent;
  cursor: pointer;
}

.nav-toggle__bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--color-text);
  transform-origin: left center;
  transition: transform 0.25s ease, opacity 0.2s ease;
}

[data-nav-header][data-open="true"] .nav-toggle__bar {
  background: var(--color-yellow);
}

[data-nav-header][data-open="true"] .nav-toggle__bar:nth-child(1) {
  transform: rotate(45deg) translateX(2px);
}

[data-nav-header][data-open="true"] .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}

[data-nav-header][data-open="true"] .nav-toggle__bar:nth-child(3) {
  transform: rotate(-45deg) translateX(2px);
}

/* ============ 页脚 ============ */
.site-footer {
  position: relative;
  margin-top: auto;
  background:
    linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px) 0 0 / 44px 44px,
    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px) 0 0 / 44px 44px,
    var(--color-bg-footer);
  border-top: 1px solid var(--color-border);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 42%;
  height: 3px;
  background: linear-gradient(90deg, var(--color-red) 0 60%, var(--color-yellow) 60% 100%);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr 1fr 1.2fr;
  gap: 2.5rem;
  padding-top: 3.25rem;
  padding-bottom: 2.5rem;
}

.site-footer__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.site-brand--footer {
  margin-bottom: 0.9rem;
}

.site-footer .site-brand__name {
  font-size: 1.25rem;
}

.site-footer__statement {
  max-width: 32rem;
  margin-top: 0.25rem;
  padding-left: 0.9rem;
  border-left: 2px solid var(--color-cite);
  font-size: 0.92rem;
  color: var(--color-text-dim);
}

.site-footer__nav {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.site-footer__heading {
  margin-bottom: 0.75rem;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--color-yellow);
}

.site-footer__nav a {
  display: inline-block;
  padding: 0.14rem 0 0.14rem 0.5rem;
  border-left: 2px solid transparent;
  font-size: 0.92rem;
  color: var(--color-text-dim);
  transition: color 0.2s, border-color 0.2s;
}

.site-footer__nav a:hover {
  border-left-color: var(--color-red);
  color: var(--color-blue);
}

.site-footer__contact {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  font-size: 0.92rem;
  color: var(--color-text-dim);
}

.site-footer__note {
  margin-top: 0.5rem;
  padding-top: 0.75rem;
  border-top: 1px dashed var(--color-border);
  font-size: 0.85rem;
  color: var(--color-text-faint);
}

.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  padding-top: 1.25rem;
  padding-bottom: 1.5rem;
  border-top: 1px solid var(--color-border);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  color: var(--color-text-faint);
}

/* ============ 页面内容骨架 ============ */
.page-title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.9rem, 4vw, 3.5rem);
  line-height: 1.15;
  letter-spacing: 0.02em;
}

.page-lede {
  max-width: 42em;
  margin-top: 1rem;
  color: var(--color-text-dim);
  font-size: clamp(1rem, 2vw, 1.15rem);
}

.section {
  padding-block: var(--space-8) var(--space-7);
}

.section--wide {
  background: var(--color-bg-card);
  border-block: 1px solid var(--color-border);
}

.section--narrow {
  max-width: 46em;
  margin-inline: auto;
}

.section-head {
  position: relative;
  margin-bottom: var(--space-6);
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
}

.section-head::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 4.5rem;
  height: 3px;
  background: var(--color-red);
  clip-path: polygon(0 0, calc(100% - 8px) 0, 100% 100%, 0 100%);
}

.section-kicker {
  display: block;
  margin-bottom: 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-blue);
}

.section-title {
  font-size: clamp(1.4rem, 3vw, 2.25rem);
}

.section-index {
  display: block;
  margin-bottom: 0.25rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--color-red);
}

.speedline {
  display: block;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--color-red) 0 60%, var(--color-yellow) 60% 80%, var(--color-blue) 80% 100%);
  clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 100%, 0 100%);
}

.grid {
  display: grid;
  gap: 1.5rem;
}

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

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

.grid--4 {
  grid-template-columns: repeat(4, 1fr);
}

/* ============ 按钮与标签 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.5rem;
  border: 1px solid var(--color-border-strong);
  background: transparent;
  color: var(--color-text);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: background 0.2s, color 0.2s, border-color 0.2s;
}

.btn:hover {
  border-color: var(--color-blue);
  background: rgba(0, 229, 255, 0.06);
  color: var(--color-blue);
}

.btn--primary {
  background: var(--color-red);
  border-color: var(--color-red);
  color: #fff;
}

.btn--primary:hover {
  background: #d92e25;
  border-color: var(--color-red);
  color: #fff;
}

.btn--yellow {
  background: var(--color-yellow);
  border-color: var(--color-yellow);
  color: #0b0c10;
}

.btn--yellow:hover {
  background: #e6c100;
  border-color: var(--color-yellow);
  color: #0b0c10;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.18rem 0.55rem;
  border: 1px solid var(--color-border-strong);
  background: var(--color-bg-card);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  white-space: nowrap;
  color: var(--color-text-dim);
}

.tag--red {
  color: var(--color-red);
  border-color: rgba(255, 59, 48, 0.45);
}

.tag--yellow {
  color: var(--color-yellow);
  border-color: rgba(255, 214, 0, 0.45);
}

.tag--blue {
  color: var(--color-blue);
  border-color: rgba(0, 229, 255, 0.45);
}

.tag--green {
  color: var(--color-green);
  border-color: rgba(122, 139, 90, 0.6);
}

.card {
  display: block;
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  background: var(--color-bg-card);
  color: var(--color-text);
  transition: border-color 0.25s, transform 0.25s;
}

.card:hover {
  border-color: var(--color-red);
  transform: translateY(-2px);
}

.card--data {
  border-top: 3px solid var(--color-red);
}

.card--data:hover {
  border-top-color: var(--color-yellow);
}

.panel {
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  background: var(--color-bg-card);
}

.panel--note {
  border-left: 3px solid var(--color-blue);
}

.panel--cite {
  border-left: 3px solid var(--color-cite);
}

.plate {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.9rem;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--color-text-dim);
}

.plate::before {
  content: "";
  width: 0.55rem;
  height: 0.55rem;
  background: var(--color-red);
  transform: skewX(-16deg);
}

/* ============ 数据组件 ============ */
.data-list {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.data-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.45rem 0;
  border-bottom: 1px dashed var(--color-border);
}

.data-label {
  font-size: 0.85rem;
  color: var(--color-text-dim);
}

.data-value {
  font-size: 0.95rem;
  color: var(--color-text);
}

.data-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.stat {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: clamp(1.8rem, 5vw, 3rem);
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}

.stat--red {
  color: var(--color-red);
}

.stat--yellow {
  color: var(--color-yellow);
}

.stat--blue {
  color: var(--color-blue);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.data-table th,
.data-table td {
  padding: 0.65rem 0.7rem;
  border-bottom: 1px solid var(--color-border);
  text-align: left;
}

.data-table th {
  background: var(--color-bg-card);
  font-family: var(--font-head);
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--color-yellow);
}

.data-table td {
  color: var(--color-text-dim);
}

.data-table td.data-num {
  color: var(--color-text);
}

/* ============ 折叠与页签 ============ */
.collapse {
  border: 1px solid var(--color-border);
  background: var(--color-bg-card);
}

.collapse__trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  width: 100%;
  padding: 1rem 1.25rem;
  border: 0;
  background: none;
  color: var(--color-text);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.95rem;
  text-align: left;
  cursor: pointer;
}

.collapse__trigger[aria-expanded="true"] {
  color: var(--color-yellow);
}

.collapse__icon {
  position: relative;
  width: 14px;
  height: 14px;
  flex: none;
}

.collapse__icon::before,
.collapse__icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  background: var(--color-blue);
  transform: translate(-50%, -50%);
}

.collapse__icon::before {
  width: 14px;
  height: 2px;
}

.collapse__icon::after {
  width: 2px;
  height: 14px;
  transition: transform 0.2s;
}

.collapse__trigger[aria-expanded="true"] .collapse__icon::after {
  transform: translate(-50%, -50%) scaleY(0);
}

.collapse__panel {
  padding: 0.25rem 1.25rem 1.25rem;
  color: var(--color-text-dim);
}

.collapse__panel[hidden] {
  display: none;
}

.tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  border-bottom: 1px solid var(--color-border);
}

.tab-button {
  padding: 0.6rem 1.2rem;
  border: 1px solid transparent;
  border-bottom: none;
  background: none;
  color: var(--color-text-dim);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.88rem;
  cursor: pointer;
}

.tab-button.is-active {
  border-color: var(--color-border);
  background: var(--color-bg-card);
  color: var(--color-yellow);
}

.tab-panel {
  padding: 1.5rem;
  border: 1px solid var(--color-border);
  border-top: none;
  background: var(--color-bg-card);
}

.tab-panel[hidden] {
  display: none;
}

/* ============ 面包屑、目录、图片框 ============ */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 1rem 0;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--color-text-faint);
}

.breadcrumbs a {
  color: var(--color-text-dim);
}

.breadcrumbs a:hover {
  color: var(--color-blue);
}

.breadcrumbs__sep {
  color: var(--color-border-strong);
}

.breadcrumbs [aria-current] {
  color: var(--color-yellow);
}

.directory {
  margin: var(--space-7) 0;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.directory__list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  list-style: none;
  margin: 0;
  padding: 0;
}

.directory__item + .directory__item {
  border-left: 1px solid var(--color-border);
}

.directory__link {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  padding: 1.1rem;
  color: var(--color-text);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1rem;
  transition: background 0.2s, color 0.2s;
}

.directory__link:hover {
  background: var(--color-bg-card);
  color: var(--color-yellow);
}

.directory__index {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--color-red);
}

.img-frame {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border: 1px solid var(--color-border);
  background:
    linear-gradient(135deg, transparent 0 58%, rgba(255, 214, 0, 0.12) 58% 59%, rgba(0, 229, 255, 0.06) 59% 60%, transparent 60%) 0 0 / 100% 100%,
    var(--color-bg-card);
}

.img-frame::before {
  content: "";
  position: absolute;
  inset: 0.9rem;
  border: 1px solid var(--color-border);
  background: repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.02) 0 10px, transparent 10px 20px);
  pointer-events: none;
}

.img-frame__label {
  position: relative;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  color: var(--color-text-faint);
}

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

.img-frame--ratio-1-1 {
  aspect-ratio: 1 / 1;
}

/* ============ 返回顶部与显现交互 ============ */
.back-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 900;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  border: 1px solid var(--color-border-strong);
  background: var(--color-bg-card);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s;
}

.back-top::before {
  content: "\2191";
  font-family: var(--font-mono);
  font-size: 1.2rem;
  line-height: 1;
  color: var(--color-yellow);
}

.back-top:hover {
  border-color: var(--color-red);
}

.back-top:hover::before {
  color: var(--color-red);
}

.back-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

html.js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.55s ease, transform 0.6s ease;
}

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

/* ============ 响应式 ============ */
@media (max-width: 1024px) {
  .site-brand__tagline {
    display: none;
  }

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

  .grid--3,
  .grid--4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .site-header__status {
    display: none;
  }

  .site-header__meta-inner {
    justify-content: flex-end;
  }

  .site-header__main-inner {
    flex-wrap: wrap;
    gap: 0;
    min-height: 3.75rem;
  }

  .site-brand__mark {
    width: 2rem;
    height: 2rem;
    font-size: 1rem;
  }

  .site-brand__name {
    font-size: 1.15rem;
  }

  .nav-toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .nav-lower {
    display: none;
    order: 3;
    flex-basis: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin-left: 0;
    padding-top: 0.5rem;
  }

  [data-nav-header][data-open="true"] .nav-lower {
    display: flex;
  }

  .nav-lower__link {
    width: 100%;
    padding: 0.72rem 0.3rem;
    border-bottom: 1px dashed var(--color-border);
    font-size: 1rem;
  }

  .nav-lower__link::after {
    display: none;
  }

  .nav-lower__link[aria-current="page"] {
    color: var(--color-yellow);
  }

  .section {
    padding-block: var(--space-6) var(--space-5);
  }

  .card {
    padding: 1.25rem;
  }

  .grid--2,
  .grid--3,
  .grid--4 {
    grid-template-columns: 1fr;
  }

  .directory__item + .directory__item {
    border-left: 0;
    border-top: 1px solid var(--color-border);
  }
}

@media (max-width: 640px) {
  .site-footer__grid {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }

  .site-footer__bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .back-top {
    right: 1rem;
    bottom: 1rem;
  }
}

/* ============ 减弱动效 ============ */
@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;
  }

  .status-dot {
    animation: none;
  }

  .card:hover,
  .back-top,
  [data-reveal] {
    transform: none;
    transition: none;
  }

  html.js [data-reveal],
  html.js [data-reveal]:not(.is-visible) {
    opacity: 1;
    transform: none;
  }
}