:root {
  --bg: #f6f8fb;
  --surface: #ffffff;
  --surface-muted: #eef3f6;
  --text: #182321;
  --muted: #5b6864;
  --line: #d8e0e3;
  --primary: #0f766e;
  --primary-dark: #0a5d57;
  --secondary: #2563eb;
  --accent: #d94635;
  --danger: #b42318;
  --shadow: 0 12px 32px rgba(16, 28, 35, 0.1);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  letter-spacing: 0;
}

img,
svg {
  display: block;
}

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

a {
  color: inherit;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -48px;
  z-index: 20;
  border-radius: var(--radius);
  background: var(--text);
  color: #fff;
  padding: 10px 14px;
  transition: top 180ms ease;
}

.skip-link:focus {
  top: 12px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid rgba(216, 224, 227, 0.9);
  background: rgba(246, 248, 251, 0.92);
  backdrop-filter: blur(14px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  color: var(--text);
  font-weight: 800;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 36px;
  height: 36px;
  place-items: center;
  border-radius: var(--radius);
  background: var(--primary);
  color: #fff;
}

.brand-mark svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.top-nav {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.top-nav a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  border-radius: 6px;
  padding: 0 14px;
  color: var(--muted);
  font-weight: 700;
  text-decoration: none;
  transition: background 180ms ease, color 180ms ease;
}

.top-nav a:hover,
.top-nav a:focus-visible,
.top-nav a.is-active {
  background: var(--primary);
  color: #fff;
  outline: none;
}

.view {
  min-height: calc(100dvh - 73px);
}

.band {
  padding: 36px 20px;
}

.band-tight {
  padding: 24px 20px;
}

.band-white {
  background: var(--surface);
  border-block: 1px solid var(--line);
}

.container {
  width: min(100%, var(--max));
  margin: 0 auto;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(320px, 0.9fr);
  gap: 28px;
  align-items: center;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--primary-dark);
  font-size: 0.9rem;
  font-weight: 800;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 16px;
  font-size: 2.45rem;
  line-height: 1.14;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 12px;
  font-size: 1.55rem;
  line-height: 1.25;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 8px;
  font-size: 1.05rem;
  line-height: 1.3;
  letter-spacing: 0;
}

.lead {
  max-width: 720px;
  color: var(--muted);
  font-size: 1.05rem;
}

.hero-actions {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 10px;
  max-width: 720px;
  margin-top: 26px;
}

.search-box {
  position: relative;
}

.search-box svg {
  position: absolute;
  left: 15px;
  top: 50%;
  width: 20px;
  height: 20px;
  transform: translateY(-50%);
  fill: none;
  stroke: var(--muted);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
  pointer-events: none;
}

.search-input,
.field,
.textarea,
.select {
  width: 100%;
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  padding: 12px 14px;
  outline: none;
  transition: border-color 180ms ease, box-shadow 180ms ease;
}

.search-input {
  padding-left: 46px;
}

.sidebar-search {
  display: block;
  margin-bottom: 14px;
}

.textarea {
  min-height: 210px;
  resize: vertical;
}

.search-input:focus,
.field:focus,
.textarea:focus,
.select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.18);
}

.hero-media {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.hero-media img {
  width: 100%;
  aspect-ratio: 5 / 3;
  object-fit: cover;
}

.hero-media-caption {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--line);
}

.stat {
  min-height: 72px;
  background: var(--surface);
  padding: 12px;
}

.stat strong {
  display: block;
  font-size: 1.2rem;
  line-height: 1.2;
}

.stat span {
  color: var(--muted);
  font-size: 0.86rem;
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.section-head p {
  margin-bottom: 0;
  color: var(--muted);
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.category-card {
  display: grid;
  overflow: hidden;
  min-height: 100%;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  text-align: left;
  cursor: pointer;
  transition: border-color 180ms ease, box-shadow 180ms ease, transform 180ms ease;
}

.category-card:hover,
.category-card:focus-visible,
.category-card.is-active {
  border-color: var(--primary);
  box-shadow: 0 10px 28px rgba(15, 118, 110, 0.16);
  outline: none;
  transform: translateY(-2px);
}

.category-card img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: var(--surface-muted);
}

.category-body {
  padding: 16px;
}

.category-title {
  display: block;
  margin-bottom: 8px;
  color: var(--text);
  font-size: 1.05rem;
  font-weight: 800;
  line-height: 1.3;
}

.category-copy {
  display: block;
  margin-bottom: 12px;
  color: var(--muted);
}

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

.pill {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  border-radius: 999px;
  background: var(--surface-muted);
  color: var(--muted);
  padding: 4px 10px;
  font-size: 0.86rem;
  font-weight: 700;
}

.content-layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 20px;
  align-items: start;
}

.sidebar-panel {
  position: sticky;
  top: 94px;
}

.filter-list {
  display: grid;
  gap: 8px;
}

.filter-button {
  display: flex;
  width: 100%;
  min-height: 48px;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  padding: 10px 12px;
  text-align: left;
  cursor: pointer;
  transition: border-color 180ms ease, background 180ms ease;
}

.filter-button:hover,
.filter-button:focus-visible,
.filter-button.is-active {
  border-color: var(--primary);
  background: #e9f7f5;
  outline: none;
}

.tutorial-list {
  display: grid;
  gap: 14px;
}

.tutorial-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 18px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  padding: 18px;
}

.tutorial-card p {
  margin-bottom: 12px;
  color: var(--muted);
}

.tutorial-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: flex-end;
}

.button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 10px 14px;
  font-weight: 800;
  text-decoration: none;
  cursor: pointer;
  transition: background 180ms ease, border-color 180ms ease, color 180ms ease, transform 180ms ease;
}

.button:focus-visible {
  outline: 3px solid rgba(15, 118, 110, 0.3);
  outline-offset: 2px;
}

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

.button:disabled {
  cursor: not-allowed;
  opacity: 0.55;
  transform: none;
}

.button-primary {
  background: var(--primary);
  color: #fff;
}

.button-primary:hover {
  background: var(--primary-dark);
}

.button-secondary {
  border-color: var(--line);
  background: var(--surface);
  color: var(--text);
}

.button-secondary:hover {
  border-color: var(--primary);
  color: var(--primary-dark);
}

.button-accent {
  background: var(--accent);
  color: #fff;
}

.button-danger {
  border-color: rgba(180, 35, 24, 0.28);
  background: #fff2f0;
  color: var(--danger);
}

.button-ghost {
  border-color: transparent;
  background: transparent;
  color: var(--muted);
}

.button-small {
  min-height: 38px;
  padding: 7px 10px;
  font-size: 0.92rem;
}

.empty {
  border: 1px dashed var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.65);
  padding: 28px;
  color: var(--muted);
  text-align: center;
}

.choose-device {
  min-height: 120px;
  display: grid;
  place-items: center;
}

.article-panel {
  margin-top: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.article-page {
  display: grid;
  gap: 14px;
}

.article-page-panel {
  margin-top: 0;
}

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

.article-header {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 18px;
  border-bottom: 1px solid var(--line);
  padding: 20px;
}

.article-header p {
  margin-bottom: 0;
  color: var(--muted);
}

.article-content {
  padding: 20px;
}

.article-content h3 {
  margin-top: 22px;
  margin-bottom: 10px;
}

.article-content h3:first-child {
  margin-top: 0;
}

.article-content ol,
.article-content ul {
  padding-left: 22px;
}

.content-image {
  margin: 18px 0;
}

.content-image img {
  width: 100%;
  max-height: 720px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface-muted);
  object-fit: contain;
}

.content-image figcaption {
  margin-top: 8px;
  color: var(--muted);
  font-size: 0.92rem;
  text-align: center;
}

.download-list {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.download-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 12px;
}

.download-row p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.admin-shell {
  display: grid;
  gap: 22px;
}

.login-panel,
.admin-panel {
  border-block: 1px solid var(--line);
  background: var(--surface);
}

.admin-panel-inner,
.login-inner {
  width: min(100%, var(--max));
  margin: 0 auto;
  padding: 28px 20px;
}

.login-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 430px);
  gap: 28px;
  align-items: center;
}

.login-image {
  overflow: hidden;
  border-radius: var(--radius);
}

.login-image img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.form-grid .span-2 {
  grid-column: 1 / -1;
}

.field-label {
  display: grid;
  gap: 6px;
  color: var(--text);
  font-weight: 800;
}

.field-label span {
  color: var(--muted);
  font-size: 0.88rem;
  font-weight: 600;
}

.admin-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

.admin-tab {
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--muted);
  padding: 8px 12px;
  font-weight: 800;
  cursor: pointer;
}

.admin-tab.is-active,
.admin-tab:hover,
.admin-tab:focus-visible {
  border-color: var(--primary);
  background: #e9f7f5;
  color: var(--primary-dark);
  outline: none;
}

.admin-grid {
  display: grid;
  grid-template-columns: minmax(280px, 0.85fr) minmax(0, 1.15fr);
  gap: 22px;
  align-items: start;
}

.admin-list {
  display: grid;
  gap: 10px;
}

.admin-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  padding: 14px;
}

.admin-item h3 {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 6px;
}

.admin-item p {
  margin-bottom: 10px;
  color: var(--muted);
}

.admin-item-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.form-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  margin-top: 16px;
}

.download-editor {
  display: grid;
  gap: 10px;
}

.download-editor-row {
  display: grid;
  grid-template-columns: minmax(120px, 0.85fr) minmax(160px, 1.2fr) minmax(120px, 0.85fr) auto;
  gap: 8px;
  align-items: start;
}

.data-tools {
  display: grid;
  gap: 12px;
  margin-top: 16px;
}

.json-box {
  min-height: 180px;
  font-family: Consolas, "Courier New", monospace;
  font-size: 0.9rem;
}

.toast {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 30;
  max-width: min(420px, calc(100vw - 40px));
  border-radius: var(--radius);
  background: var(--text);
  color: #fff;
  padding: 12px 14px;
  box-shadow: var(--shadow);
}

.toast.is-error {
  background: var(--danger);
}

.sr-only {
  position: absolute;
  overflow: hidden;
  width: 1px;
  height: 1px;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
}

@media (max-width: 900px) {
  .hero-grid,
  .content-layout,
  .admin-grid,
  .login-inner {
    grid-template-columns: 1fr;
  }

  .sidebar-panel {
    position: static;
  }

  .category-grid {
    grid-template-columns: 1fr;
  }

  .tutorial-card {
    grid-template-columns: 1fr;
  }

  .tutorial-actions {
    justify-content: flex-start;
  }

  .hero-actions {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .header-inner {
    align-items: stretch;
    flex-direction: column;
    padding-inline: 14px;
  }

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

  .band,
  .band-tight,
  .admin-panel-inner,
  .login-inner {
    padding-inline: 14px;
  }

  h1 {
    font-size: 2rem;
  }

  .section-head,
  .article-header {
    align-items: stretch;
    flex-direction: column;
  }

  .download-row,
  .form-grid,
  .download-editor-row {
    grid-template-columns: 1fr;
  }

  .hero-media-caption {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}