/* OPPO Store Help — shared documentation styles (HTML + CSS only) */

:root {
  --bg: #fafafa;
  --surface: #ffffff;
  --text: #1a1c1e;
  --text-muted: #5f6368;
  --border: #e0e3e7;
  --accent: #0f9d58;
  --accent-soft: rgba(15, 157, 88, 0.08);
  --header-h: 3.25rem;
  --content-max: 42rem;
  --radius: 6px;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "Cascadia Code", "Source Code Pro", Menlo, Consolas, monospace;
}

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

html {
  font-size: 100%;
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: calc(var(--header-h) + 1rem);
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.15em;
}

a:hover {
  text-decoration-thickness: 2px;
}

a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  z-index: 999;
  padding: 0.5rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
}

.skip-link:focus {
  left: 0.5rem;
  top: 0.5rem;
}

.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;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.04);
}

.site-header__inner {
  max-width: 72rem;
  margin: 0 auto;
  padding: 0.65rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  min-height: var(--header-h);
}

.site-title {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.site-title a {
  color: var(--text);
  text-decoration: none;
}

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

.site-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem 1rem;
  font-size: 0.9rem;
}

.site-nav a {
  color: var(--text-muted);
  text-decoration: none;
  padding: 0.25rem 0;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: var(--text);
  text-decoration: underline;
  text-decoration-color: var(--accent);
}

main {
  max-width: 72rem;
  margin: 0 auto;
  padding: 1.75rem 1.25rem 3rem;
}

.page-header {
  margin-bottom: 2rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border);
}

.page-header h1 {
  margin: 0 0 0.5rem;
  font-size: clamp(1.5rem, 4vw, 1.85rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.25;
}

.lead {
  margin: 0;
  font-size: 1.05rem;
  line-height: 1.62;
  color: var(--text-muted);
  max-width: var(--content-max);
}

.home .lead {
  max-width: 46rem;
}

.content-narrow {
  max-width: var(--content-max);
}

.breadcrumb {
  margin: 0 0 1rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.breadcrumb ol {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem;
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.breadcrumb li:not(:last-child)::after {
  content: "/";
  color: var(--border);
  font-weight: 400;
}

.breadcrumb a {
  color: var(--text-muted);
}

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

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
  margin: 1rem 0 1.75rem;
  padding: 0.85rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.875rem;
  color: var(--text-muted);
}

.article-meta dt {
  margin: 0;
  font-weight: 600;
  color: var(--text);
}

.article-meta dd {
  margin: 0.15rem 0 0;
}

.article-meta > div {
  min-width: 8rem;
}

.prose {
  max-width: var(--content-max);
}

.prose h2 {
  margin: 2rem 0 0.75rem;
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  padding-top: 0.25rem;
  border-top: 1px solid var(--border);
}

.prose h2:first-of-type {
  margin-top: 0;
  border-top: none;
  padding-top: 0;
}

.prose h3 {
  margin: 1.5rem 0 0.5rem;
  font-size: 1.05rem;
  font-weight: 600;
}

.prose p {
  margin: 0 0 1rem;
}

.prose ul,
.prose ol {
  margin: 0 0 1rem;
  padding-left: 1.35rem;
}

.prose li {
  margin-bottom: 0.35rem;
}

.prose code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--accent-soft);
  padding: 0.12em 0.35em;
  border-radius: 4px;
}

.prose pre {
  margin: 1rem 0;
  padding: 1rem;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.5;
  background: #f1f3f4;
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.prose pre code {
  background: none;
  padding: 0;
}

.note {
  margin: 1.25rem 0;
  padding: 0.85rem 1rem;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: 0.95rem;
}

.note p:last-child {
  margin-bottom: 0;
}

.faq {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  max-width: var(--content-max);
}

.faq h2 {
  margin: 0 0 1rem;
  font-size: 1.15rem;
  font-weight: 600;
}

.faq details {
  margin-bottom: 0.65rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}

.faq summary {
  padding: 0.75rem 1rem;
  cursor: pointer;
  font-weight: 500;
  list-style: none;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq details[open] summary {
  border-bottom: 1px solid var(--border);
}

.faq .faq-answer {
  padding: 0 1rem 1rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.related {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
  max-width: var(--content-max);
}

.related h2 {
  margin: 0 0 0.75rem;
  font-size: 1.05rem;
  font-weight: 600;
}

.related ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.related li {
  margin-bottom: 0.5rem;
}

.card-list {
  display: grid;
  gap: 0.75rem;
  margin: 1.25rem 0 0;
  padding: 0;
  list-style: none;
}

.card-list a {
  display: block;
  padding: 1rem 1.1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  text-decoration: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.card-list a:hover {
  border-color: var(--accent);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.card-list .meta {
  display: block;
  margin-top: 0.35rem;
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* Homepage — documentation-style sections */
.home section + section {
  margin-top: 2.5rem;
  padding-top: 1.85rem;
  border-top: 1px solid var(--border);
}

.home-section__head {
  margin-bottom: 1.1rem;
  max-width: 46rem;
}

.home-section__title {
  margin: 0 0 0.35rem;
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.3;
  color: var(--text);
}

.home-section__intro {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--text-muted);
  max-width: var(--content-max);
  line-height: 1.58;
}

.home-section__intro + .home-section__intro {
  margin-top: 0.65rem;
}

.home-panel {
  margin-top: 0.35rem;
  padding: 1.25rem 1.35rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.03);
}

.home-panel--flush {
  padding: 0;
}

.home-panel .card-list {
  margin-top: 0;
  gap: 0.85rem;
}

.home-panel .topic-list {
  margin-top: 0;
  max-width: none;
}

/* Coverage summary — compact hub overview */
.home-coverage {
  margin-top: 1.15rem;
  padding: 1rem 1.2rem;
  max-width: 46rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.03);
}

.home-coverage__label {
  margin: 0;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.home-coverage__list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.55rem;
  margin: 0.75rem 0 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 520px) {
  .home-coverage__list {
    grid-template-columns: 1fr 1fr;
    gap: 0.6rem 0.85rem;
  }
}

.home-coverage__list li {
  min-height: 100%;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
}

.home-coverage__block {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  height: 100%;
  padding: 0.65rem 0.75rem;
  color: inherit;
  text-decoration: none;
  border-radius: calc(var(--radius) - 1px);
  transition: background-color 0.12s ease;
}

.home-coverage__block:hover {
  background: var(--accent-soft);
}

.home-coverage__block:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.home-coverage__link {
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--text);
  letter-spacing: -0.01em;
}

.home-coverage__block:hover .home-coverage__link {
  color: var(--accent);
}

.home-coverage__hint {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.45;
}

/* Homepage article rows — single panel, clear scan line */
.article-card-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.article-card-list li {
  margin: 0;
}

.article-card {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.3rem;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  text-decoration: none;
  transition: background-color 0.12s ease;
}

.article-card:last-child {
  border-bottom: none;
}

.article-card:hover {
  background: var(--accent-soft);
}

.article-card:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.article-card__title {
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: -0.02em;
  line-height: 1.35;
}

.article-card__desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.article-card__cta {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
  margin-top: 0.2rem;
}

.article-card:hover .article-card__cta {
  text-decoration: underline;
  text-underline-offset: 0.15em;
}

.home .page-header {
  margin-bottom: 2.25rem;
  padding-bottom: 1.35rem;
}

.home-intro {
  margin: 0.95rem 0 0;
  font-size: 1.02rem;
  color: var(--text-muted);
  max-width: 46rem;
  line-height: 1.65;
}

.home-intro + .home-intro {
  margin-top: 0.75rem;
}

.about-blurb {
  margin: 0;
  font-size: 0.95rem;
  color: var(--text-muted);
  max-width: var(--content-max);
  line-height: 1.65;
}

.about-blurb + .about-blurb {
  margin-top: 0.75rem;
}

.topic-list {
  margin: 0.25rem 0 0;
  padding: 0;
  list-style: none;
  max-width: var(--content-max);
}

.topic-list li {
  margin-bottom: 0.85rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--border);
}

.topic-list li:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: none;
}

.topic-list a {
  display: block;
  color: var(--text);
  text-decoration: none;
}

.topic-list a:hover .topic-list__title {
  color: var(--accent);
}

.topic-list__title {
  display: block;
  font-weight: 500;
  font-size: 1rem;
  line-height: 1.35;
}

.topic-list__hint {
  display: block;
  margin-top: 0.25rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.45;
  font-weight: 400;
}

.site-footer {
  margin-top: auto;
  padding: 1.5rem 1.25rem 2rem;
  border-top: 1px solid var(--border);
  background: var(--surface);
  font-size: 0.875rem;
  color: var(--text-muted);
}

.site-footer__inner {
  max-width: 72rem;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
}

.site-footer a {
  color: var(--text-muted);
}

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

body {
  display: flex;
  flex-direction: column;
}

/* Contact form — no JS; works as static structure, server can wire POST later */
.form-stack label {
  display: block;
  margin-bottom: 0.35rem;
  font-size: 0.9rem;
  font-weight: 500;
}

.form-stack input,
.form-stack textarea {
  width: 100%;
  max-width: 28rem;
  margin-bottom: 1rem;
  padding: 0.6rem 0.75rem;
  font: inherit;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}

.form-stack textarea {
  min-height: 8rem;
  resize: vertical;
}

.btn {
  display: inline-block;
  padding: 0.55rem 1.1rem;
  font: inherit;
  font-size: 0.95rem;
  font-weight: 500;
  color: #fff;
  background: var(--accent);
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
}

.btn:hover {
  filter: brightness(0.95);
}

@media (max-width: 640px) {
  .site-header__inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .site-nav {
    width: 100%;
    border-top: 1px solid var(--border);
    padding-top: 0.65rem;
  }
}