@layer reset, base, theme, components, utilities;

@layer reset {
  html {
    box-sizing: border-box;
    -webkit-text-size-adjust: 100%;
  }

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

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

  ul, ol {
    padding-inline-start: 0;
    list-style: none;
  }

  img, svg {
    display: block;
    max-inline-size: 100%;
  }

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

@layer theme {
  :root {
    --ita-red-primary: #D81C23;
    --ita-red-cta: #D40E14;
    --ita-red-hover: #8F0004;
    --ita-red-alert: #EB0303;
    --ita-topbar: #4D4D4D;
    --ita-brand-muted: #808080;

    --ita-bg-light: #FFFFFF;
    --ita-bg-dark: #121417;
    --ita-surface-1-light: #F2F2F2;
    --ita-surface-1-dark: #1B1E23;
    --ita-surface-2-light: #E5E5E6;
    --ita-surface-2-dark: #262A31;
    --ita-ink-light: #111111;
    --ita-ink-dark: #F3F4F6;
    --ita-muted-light: #595959;
    --ita-muted-dark: #A1A7B3;
    --ita-border-light: #D1D5DB;
    --ita-border-dark: #374151;
    --ita-ok-light: #166534;
    --ita-ok-dark: #4ADE80;
    --ita-warn-light: #9A3412;
    --ita-warn-dark: #FBBF24;

    --color-bg: var(--ita-bg-light);
    --color-surface: var(--ita-surface-1-light);
    --color-surface-alt: var(--ita-surface-2-light);
    --color-ink: var(--ita-ink-light);
    --color-muted: var(--ita-muted-light);
    --color-border: var(--ita-border-light);
    --color-ok: var(--ita-ok-light);
    --color-warn: var(--ita-warn-light);

    --radius-card: 24px;
    --radius-btn: 8px;
    --radius-pill: 9999px;
    --shadow-card: 0 0 10px 0 rgba(0, 0, 0, 0.15);
    --font-heading: "Noto Sans", "Segoe UI", system-ui, -apple-system, sans-serif;
    --font-body: "PT Sans", "Segoe UI", system-ui, -apple-system, sans-serif;
    --font-badge: "Roboto", "Segoe UI", system-ui, -apple-system, sans-serif;

    color-scheme: light dark;
    accent-color: var(--ita-red-primary);
  }

  :root:has(> head > meta[name="color-scheme"][content="dark"]) {
    color-scheme: dark;
    --color-bg: var(--ita-bg-dark);
    --color-surface: var(--ita-surface-1-dark);
    --color-surface-alt: var(--ita-surface-2-dark);
    --color-ink: var(--ita-ink-dark);
    --color-muted: var(--ita-muted-dark);
    --color-border: var(--ita-border-dark);
    --color-ok: var(--ita-ok-dark);
    --color-warn: var(--ita-warn-dark);
  }

  :root:has(> head > meta[name="color-scheme"][content="light"]) {
    color-scheme: light;
  }

  @media (prefers-color-scheme: dark) {
    :root:not(:has(> head > meta[name="color-scheme"][content="light"])) {
      --color-bg: var(--ita-bg-dark);
      --color-surface: var(--ita-surface-1-dark);
      --color-surface-alt: var(--ita-surface-2-dark);
      --color-ink: var(--ita-ink-dark);
      --color-muted: var(--ita-muted-dark);
      --color-border: var(--ita-border-dark);
      --color-ok: var(--ita-ok-dark);
      --color-warn: var(--ita-warn-dark);
    }
  }

  @supports (color: light-dark(white, black)) {
    :root {
      --color-bg: light-dark(var(--ita-bg-light), var(--ita-bg-dark));
      --color-surface: light-dark(var(--ita-surface-1-light), var(--ita-surface-1-dark));
      --color-surface-alt: light-dark(var(--ita-surface-2-light), var(--ita-surface-2-dark));
      --color-ink: light-dark(var(--ita-ink-light), var(--ita-ink-dark));
      --color-muted: light-dark(var(--ita-muted-light), var(--ita-muted-dark));
      --color-border: light-dark(var(--ita-border-light), var(--ita-border-dark));
      --color-ok: light-dark(var(--ita-ok-light), var(--ita-ok-dark));
      --color-warn: light-dark(var(--ita-warn-light), var(--ita-warn-dark));
      --color-scrollbar-track: light-dark(#F2F2F2, #1B1E23);
      --color-scrollbar-thumb: light-dark(#6B6B6B, #6E7681);
      scrollbar-color: var(--color-scrollbar-thumb) var(--color-scrollbar-track);
    }
  }

  :root[data-theme="dark"] {
    color-scheme: dark;
    --color-bg: var(--ita-bg-dark);
    --color-surface: var(--ita-surface-1-dark);
    --color-surface-alt: var(--ita-surface-2-dark);
    --color-ink: var(--ita-ink-dark);
    --color-muted: var(--ita-muted-dark);
    --color-border: var(--ita-border-dark);
    --color-ok: var(--ita-ok-dark);
    --color-warn: var(--ita-warn-dark);
    --color-scrollbar-track: #1B1E23;
    --color-scrollbar-thumb: #6E7681;
  }

  :root[data-theme="light"] {
    color-scheme: light;
    --color-bg: var(--ita-bg-light);
    --color-surface: var(--ita-surface-1-light);
    --color-surface-alt: var(--ita-surface-2-light);
    --color-ink: var(--ita-ink-light);
    --color-muted: var(--ita-muted-light);
    --color-border: var(--ita-border-light);
    --color-ok: var(--ita-ok-light);
    --color-warn: var(--ita-warn-light);
    --color-scrollbar-track: #F2F2F2;
    --color-scrollbar-thumb: #6B6B6B;
  }
}

@layer base {
  body {
    font-family: var(--font-body);
    background-color: var(--color-surface);
    color: var(--color-ink);
    line-height: 1.5;
    min-block-size: 100dvb;
    display: grid;
    grid-template-rows: auto auto 1fr auto;
  }

  h1, h2, h3, h4 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.25;
  }

  a:any-link {
    color: var(--ita-red-primary);
    text-decoration-thickness: 1.5px;
    text-underline-offset: 3px;
  }

  :where(a:any-link, button, input, select, textarea, summary, [tabindex]):focus-visible {
    outline: 3px solid var(--ita-red-primary);
    outline-offset: 2px;
  }

  code, pre {
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    font-size: 0.9em;
  }
}

@layer components {
  .topbar {
    min-block-size: 32px;
    background-color: var(--ita-topbar);
    color: #FFFFFF;
    font-size: 0.8125rem;
    padding-inline: 1rem;
    display: flex;
    align-items: center;
  }

  .topbar-inner, .header-inner, .page-main, .site-footer-inner {
    inline-size: min(1440px, 100% - 2rem);
    margin-inline: auto;
  }

  .topbar-inner {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 0.5rem 1rem;
    padding-block: 0.25rem;
  }

  .topbar a:any-link {
    color: #FFFFFF;
  }

  .topbar .pill {
    background-color: var(--color-bg);
    color: var(--color-ink);
    border-color: var(--color-border);
  }
  .topbar .pill-ok { border-color: var(--color-ok); color: var(--color-ok); }
  .topbar .pill-warn { border-color: var(--color-warn); color: var(--color-warn); }
  .topbar .pill-danger {
    background-color: var(--ita-red-cta);
    border-color: rgba(255, 255, 255, 0.7);
    color: #FFFFFF;
  }

  .site-header {
    position: sticky;
    inset-block-start: 0;
    z-index: 30;
    min-block-size: 72px;
    background-color: var(--color-bg);
    border-block-end: 1px solid var(--color-border);
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.06);
    display: flex;
    align-items: center;
  }

  .header-inner {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem 1rem;
    padding-block: 0.5rem;
  }

  .brand-link {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--color-ink);
    font-family: var(--font-heading);
    font-weight: 800;
    flex-shrink: 0;
  }

  .brand-logo { display: block; block-size: 2.35rem; inline-size: auto; flex-shrink: 0; }
  .brand-logo-dark { display: none; }
  :root[data-theme="dark"] .brand-logo-light,
  :root:has(> head > meta[name="color-scheme"][content="dark"]) .brand-logo-light { display: none; }
  :root[data-theme="dark"] .brand-logo-dark,
  :root:has(> head > meta[name="color-scheme"][content="dark"]) .brand-logo-dark { display: block; }
  :root[data-theme="light"] .brand-logo-light { display: block; }
  :root[data-theme="light"] .brand-logo-dark { display: none; }
  @media (prefers-color-scheme: dark) {
    :root:not(:has(> head > meta[name="color-scheme"][content="light"])):not([data-theme="light"]) .brand-logo-light { display: none; }
    :root:not(:has(> head > meta[name="color-scheme"][content="light"])):not([data-theme="light"]) .brand-logo-dark { display: block; }
  }

  .brand-subtitle {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--color-ink);
    display: block;
  }

  .header-actions {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: flex-end;
    gap: 0.5rem;
    min-inline-size: 0;
    max-inline-size: 100%;
    margin-inline-start: auto;
  }

  .header-actions > .btn,
  .header-actions > form {
    flex-shrink: 0;
  }

  .app-shell { inline-size: min(1440px, 100% - 2rem); margin-inline: auto; }
  .app-shell > .page-main { min-inline-size: 0; inline-size: 100%; margin-inline: 0; }
  .app-sidebar { display: none; }
  .nav-groups { display: grid; gap: 0.9rem; }
  .nav-group-label {
    font-family: var(--font-heading); font-size: 0.72rem; font-weight: 800;
    text-transform: uppercase; letter-spacing: 0.06em; color: var(--color-muted);
    padding-inline: 0.65rem; margin-block-end: 0.25rem;
  }
  .nav-list { display: grid; gap: 0.2rem; }
  .nav-list a {
    display: flex; align-items: center; justify-content: space-between; gap: 0.5rem;
    min-block-size: 38px; padding: 0.4rem 0.7rem; border-radius: 6px;
    border-inline-start: 4px solid transparent; text-decoration: none;
    color: var(--color-ink); font-weight: 600; font-size: 0.92rem;
  }
  .nav-list a:hover { background-color: var(--color-surface); }
  .nav-list a[aria-current="page"] {
    background-color: var(--color-surface);
    border-inline-start: 4px solid var(--ita-red-primary);
    font-weight: 700;
  }
  @media (pointer: coarse) { .nav-list a { min-block-size: 44px; } }

  @media (min-width: 960px) {
    .mobile-menu-btn { display: none; }
    .app-shell { display: grid; grid-template-columns: 256px minmax(0, 1fr); align-items: start; gap: 1.5rem; }
    .app-sidebar {
      display: block; position: sticky; inset-block-start: calc(72px + 1rem);
      max-block-size: calc(100dvb - 72px - 2rem); overflow-y: auto;
      overscroll-behavior: contain; scrollbar-gutter: stable;
      background-color: var(--color-bg); border: 1px solid var(--color-border);
      border-radius: var(--radius-btn); padding: 0.85rem 0.75rem; margin-block: 1.5rem;
    }
  }

  .page-main { padding-block: 1.5rem 2.5rem; display: grid; gap: 1.5rem; align-content: start; }
  .doc-toc { display: flex; flex-wrap: wrap; gap: 0.45rem; }
  .doc-toc a {
    padding: 0.3rem 0.7rem; border: 1px solid var(--color-border); border-radius: var(--radius-pill);
    background-color: var(--color-surface); color: var(--color-ink); font-size: 0.84rem;
    font-weight: 600; text-decoration: none;
  }
  .doc-toc a:hover { border-color: var(--ita-red-primary); }
  .doc-list { list-style: disc; padding-inline-start: 1.3rem; display: grid; gap: 0.35rem; }
  .doc-steps { list-style: decimal; padding-inline-start: 1.3rem; display: grid; gap: 0.4rem; }
  .code-block {
    overflow-x: auto; padding: 0.85rem 1rem; border-radius: var(--radius-btn);
    border: 1px solid var(--color-border); background-color: var(--color-surface);
    font-size: 0.86rem; line-height: 1.45;
  }

  .site-footer {
    border-block-start: 1px solid var(--color-border);
    background-color: var(--color-bg);
    padding-block: 0.9rem;
    font-size: 0.85rem;
    color: var(--color-muted);
  }
  .site-footer-inner {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 0.5rem;
  }
}

@layer utilities {
  .visually-hidden:where(:not(:focus-within, :active)) {
    position: absolute;
    clip-path: inset(50%);
    overflow: hidden;
    inline-size: 1px;
    block-size: 1px;
    margin: -1px;
    padding: 0;
    border: 0;
    white-space: nowrap;
  }
  .skip-link:focus-visible {
    position: fixed;
    inset-block-start: 0.5rem;
    inset-inline-start: 0.5rem;
    z-index: 100;
    background: var(--ita-red-primary);
    color: #FFFFFF;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-btn);
    text-decoration: none;
  }
}