/* ==========================================================================
   Web Designs -4- You — Modern Site Stylesheet
   Shared design system for the entire static site.
   ========================================================================== */

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

:root {
  --color-primary: #1d4ed8;
  --color-primary-dark: #1e3a8a;
  --color-accent: #0ea5e9;
  --color-ink: #1e293b;
  --color-muted: #64748b;
  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --color-border: #e2e8f0;
  --color-soft: #eff6ff;
  --radius: 10px;
  --radius-sm: 6px;
  --shadow: 0 1px 3px rgba(15, 23, 42, 0.08), 0 1px 2px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 6px 16px rgba(15, 23, 42, 0.10);
  --maxw: 1080px;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}

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

body {
  font-family: var(--font-sans);
  color: var(--color-ink);
  background-color: var(--color-bg);
  line-height: 1.65;
  font-size: 1rem;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.25;
  color: var(--color-ink);
  margin-bottom: 0.5em;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.2rem; }
h4 { font-size: 1.05rem; }

p { margin-bottom: 1rem; }

ul, ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

li { margin-bottom: 0.35rem; }

/* --- Layout ------------------------------------------------------------ */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* --- Skip link (accessibility) ---------------------------------------- */
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--color-primary);
  color: #fff;
  padding: 0.6rem 1rem;
  border-radius: 0 0 var(--radius-sm) 0;
  z-index: 999;
}
.skip-link:focus {
  left: 0;
  color: #fff;
  text-decoration: none;
}

/* --- Header / Nav ------------------------------------------------------- */
.site-header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: var(--shadow);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 800;
  font-size: 1.15rem;
  color: var(--color-primary-dark);
}

.brand:hover { text-decoration: none; }

.brand__logo {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  color: #fff;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 900;
  font-size: 1rem;
}

.brand small {
  display: block;
  font-weight: 500;
  font-size: 0.72rem;
  color: var(--color-muted);
  letter-spacing: 0.04em;
}

.main-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  margin: 0;
  padding: 0;
}

.main-nav a {
  display: inline-block;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-sm);
  color: var(--color-ink);
  font-weight: 600;
  font-size: 0.92rem;
}

.main-nav a:hover {
  background: var(--color-soft);
  color: var(--color-primary);
  text-decoration: none;
}

.main-nav a[aria-current="page"] {
  background: var(--color-primary);
  color: #fff;
}

/* --- Breadcrumbs -------------------------------------------------------- */
.breadcrumb {
  font-size: 0.82rem;
  color: var(--color-muted);
  margin: 1rem 0 0.25rem;
}
.breadcrumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0;
  padding: 0;
}
.breadcrumb li::after { content: "›"; margin-left: 0.4rem; color: var(--color-border); }
.breadcrumb li:last-child::after { content: ""; }

/* --- Main content -------------------------------------------------------- */
.site-main {
  padding: 2rem 0 3rem;
  min-height: 60vh;
}

.page-header {
  margin-bottom: 1.75rem;
}
.page-header h1 {
  font-size: 2.1rem;
  color: var(--color-primary-dark);
}
.page-header p.lead {
  font-size: 1.1rem;
  color: var(--color-muted);
  max-width: 70ch;
}

/* --- Cards / Grid -------------------------------------------------------- */
.grid {
  display: grid;
  gap: 1.25rem;
}
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); }
.grid--4 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}
.card h2, .card h3 { color: var(--color-primary-dark); font-size: 1.1rem; }
.card p { color: var(--color-muted); font-size: 0.95rem; }
.card .card-link { font-weight: 600; }

/* --- Hero ---------------------------------------------------------------- */
.hero {
  background: linear-gradient(135deg, var(--color-primary-dark), var(--color-primary) 55%, var(--color-accent));
  color: #fff;
  border-radius: var(--radius);
  padding: 2.5rem 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-md);
}
.hero h1 { color: #fff; font-size: 2.2rem; }
.hero p { color: rgba(255, 255, 255, 0.92); font-size: 1.1rem; max-width: 68ch; }
.hero .btn { margin-top: 0.5rem; }

/* --- Section sub-nav (topic navigation) ---------------------------------- */
.section-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding: 0;
  margin: 1rem 0;
}
.section-nav a {
  display: inline-block;
  background: var(--color-soft);
  color: var(--color-primary);
  font-weight: 600;
  font-size: 0.88rem;
  border-radius: 999px;
  padding: 0.35rem 0.85rem;
}
.section-nav a:hover {
  background: var(--color-primary);
  color: #fff;
  text-decoration: none;
}

.tutorial-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

/* --- Prose (article body) & notice --------------------------------------- */
.prose {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow);
}
.prose h2 { margin-top: 1.5rem; color: var(--color-primary-dark); }
.notice {
  background: #fffbeb;
  border: 1px solid #fde68a;
  border-left: 4px solid #f59e0b;
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin: 1.25rem 0;
}

/* --- Page hero (simple intro block) -------------------------------------- */
.page-hero {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  border-radius: var(--radius);
  padding: 1.75rem 2rem;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow);
}
.page-hero h1 {
  font-size: 1.9rem;
  color: var(--color-primary-dark);
  margin-top: 0;
}
.page-hero p { color: var(--color-muted); }

/* --- Buttons ------------------------------------------------------------- */
.btn {
  display: inline-block;
  background: var(--color-primary);
  color: #fff;
  font-weight: 600;
  padding: 0.6rem 1.2rem;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  text-align: center;
}
.btn:hover { background: var(--color-primary-dark); color: #fff; text-decoration: none; }
.btn--light { background: #fff; color: var(--color-primary); }
.btn--light:hover { background: var(--color-soft); color: var(--color-primary-dark); }

/* --- Callout / Tip box ---------------------------------------------------- */
.callout {
  background: var(--color-soft);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin: 1.25rem 0;
}
.callout--warn {
  background: #fff7ed;
  border-left-color: #f59e0b;
}
.callout--tip { border-left-color: #10b981; }

/* --- Sections ------------------------------------------------------------- */
.section { margin-bottom: 2.5rem; }
.section-title {
  font-size: 1.35rem;
  color: var(--color-primary-dark);
  border-bottom: 2px solid var(--color-soft);
  padding-bottom: 0.4rem;
  margin-bottom: 1rem;
}

/* --- Content (article body) ----------------------------------------------- */
.article {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow);
}
.article h2 { margin-top: 1.5rem; }
.article h3 { margin-top: 1.25rem; }
.article code,
.article pre {
  background: var(--color-soft);
  border-radius: 4px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.9em;
}
.article code { padding: 0.1em 0.35em; }
.article pre { padding: 1rem; overflow-x: auto; margin: 1rem 0; }

/* --- FAQ ------------------------------------------------------------------- */
.faq details {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin-bottom: 0.75rem;
}
.faq summary {
  font-weight: 600;
  cursor: pointer;
  color: var(--color-primary-dark);
}
.faq details p { margin-top: 0.75rem; color: var(--color-muted); }

/* --- Feature list ---------------------------------------------------------- */
.feature-list {
  list-style: none;
  padding: 0;
}
.feature-list li {
  padding-left: 1.6rem;
  position: relative;
  margin-bottom: 0.5rem;
}
.feature-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: #10b981;
  font-weight: 700;
}

/* --- Tables ---------------------------------------------------------------- */
table.data {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.95rem;
}
table.data th, table.data td {
  border: 1px solid var(--color-border);
  padding: 0.6rem 0.85rem;
  text-align: left;
}
table.data th { background: var(--color-soft); color: var(--color-primary-dark); }

/* --- Footer ---------------------------------------------------------------- */
.site-footer {
  background: var(--color-primary-dark);
  color: rgba(255, 255, 255, 0.85);
  margin-top: 2rem;
}
.site-footer__inner {
  padding: 2.5rem 1.25rem 1.5rem;
}
.site-footer .footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  max-width: var(--maxw);
  margin: 0 auto 2rem;
}
.site-footer h3 {
  color: #fff;
  font-size: 1rem;
  margin-bottom: 0.75rem;
}
.site-footer ul {
  list-style: none;
  padding: 0;
}
.site-footer ul li { margin-bottom: 0.4rem; }
.site-footer a { color: rgba(255, 255, 255, 0.85); }
.site-footer a:hover { color: #fff; }
.site-footer__bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  text-align: center;
  font-size: 0.85rem;
  padding-top: 1rem;
  color: rgba(255, 255, 255, 0.7);
}

/* --- Misc ------------------------------------------------------------------- */
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 2rem; }
.mb-2 { margin-bottom: 1rem; }

.tag {
  display: inline-block;
  background: var(--color-soft);
  color: var(--color-primary);
  font-size: 0.78rem;
  font-weight: 600;
  border-radius: 999px;
  padding: 0.2rem 0.7rem;
  margin: 0.15rem;
}

/* --- Common utilities used by rebuilt pages -------------------------------- */
.center { text-align: center; }
.caption, figcaption { font-size: 0.85rem; color: var(--color-muted); font-style: italic; margin-top: 0.5rem; }
.lede { font-size: 1.1rem; color: var(--color-muted); line-height: 1.6; }
.tip, .note, .warning {
  border-radius: var(--radius-sm);
  padding: 0.85rem 1rem;
  margin: 1.1rem 0;
  font-size: 0.95rem;
  line-height: 1.55;
}
.tip { background: #ecfdf5; border: 1px solid #a7f3d0; border-left: 4px solid #10b981; }
.note { background: #eff6ff; border: 1px solid #bfdbfe; border-left: 4px solid var(--color-primary); }
.warning { background: #fffbeb; border: 1px solid #fde68a; border-left: 4px solid #f59e0b; }

.section-nav__title { font-weight: 700; margin: 0 0 0.4rem; color: var(--color-primary-dark); }
.sub-nav {
  background: var(--color-soft);
  border-radius: var(--radius-sm);
  padding: 0.8rem 1rem;
  margin: 1rem 0;
}
.sub-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem 1rem;
  padding: 0;
  margin: 0;
}
.sub-nav a { font-weight: 600; font-size: 0.9rem; color: var(--color-primary); }

.error-page { text-align: center; padding: 3rem 1rem; }
.error-page h1 { font-size: 2.4rem; }

.form-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  max-width: 640px;
}
.form-field { margin-bottom: 1rem; }
.form-field label { display: block; font-weight: 600; margin-bottom: 0.3rem; }
.form-field input,
.form-field textarea {
  width: 100%;
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font: inherit;
}
.form-actions { margin-top: 1rem; }
.comments-form { max-width: 640px; }

.simple-table { width: 100%; border-collapse: collapse; margin: 1rem 0; }
.simple-table th, .simple-table td { border: 1px solid var(--color-border); padding: 0.5rem 0.75rem; text-align: left; }
.simple-table th { background: var(--color-soft); font-weight: 700; }

.related-links { list-style: none; padding: 0; margin: 1rem 0; }
.related-links li { margin-bottom: 0.4rem; }
.related-links a { font-weight: 600; }

.service-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.5rem; }
.service-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}
.tagline { font-size: 1.05rem; color: var(--color-muted); }

.code-step { font-family: var(--font-mono); background: #0f172a; color: #e2e8f0; padding: 0.9rem 1.1rem; border-radius: var(--radius-sm); overflow-x: auto; }
.tutorial-chapter { margin-top: 2rem; }
.tutorial-content { line-height: 1.7; }
.tutorial-columns { columns: 2; column-gap: 2rem; }
.tutorial-figure { margin: 1.2rem 0; text-align: center; }

.include-example { background: #f1f5f9; border: 1px dashed var(--color-border); border-radius: var(--radius-sm); padding: 0.9rem 1rem; margin: 1rem 0; font-family: var(--font-mono); font-size: 0.85rem; overflow-x: auto; }
.date-demo, .drop-down-demo { background: var(--color-soft); border-radius: var(--radius-sm); padding: 1rem; margin: 1rem 0; }
.drop-down-title { font-weight: 700; margin-bottom: 0.5rem; }
.color-picker { text-align: center; margin: 1rem 0; }
.color-picker__tool { border: 1px solid var(--color-border); border-radius: var(--radius); padding: 1rem; background: var(--color-surface); }
.color-picker__note { font-size: 0.85rem; color: var(--color-muted); }

/* --- Responsive ------------------------------------------------------------- */
@media (max-width: 720px) {
  h1 { font-size: 1.6rem; }
  h2 { font-size: 1.25rem; }
  .hero { padding: 1.75rem 1.25rem; }
  .hero h1 { font-size: 1.7rem; }
  .article { padding: 1.25rem; }
  .site-header__inner { flex-direction: column; align-items: flex-start; }
  .main-nav { width: 100%; }
  .main-nav ul { flex-direction: column; width: 100%; }
  .main-nav a { width: 100%; }
}