/* ==========================================================================
   DBPC Alumni Portal — Design System
   Implements the tokens defined in docs/design/06-design-system.md.
   Token-driven, framework-free CSS. Token names mirror the Tailwind theme in
   tailwind.config.js so a future compiled-Tailwind build is a 1:1 migration.
   ========================================================================== */

/* ---- Design tokens ----------------------------------------------------- */
:root {
  /* Brand — primary (Bosco blue) */
  --color-primary-900: #062544;
  --color-primary-700: #0b3d6e;
  --color-primary-500: #1a6fb5;
  --color-primary-100: #e3eef8;
  /* Brand — accent (gold) */
  --color-accent-600: #b97b05;
  --color-accent-500: #e2a106;
  --color-accent-100: #fbefd2;
  /* Neutrals */
  --color-neutral-900: #111827;
  --color-neutral-700: #374151;
  --color-neutral-500: #6b7280;
  --color-neutral-300: #d1d5db;
  --color-neutral-100: #f3f4f6;
  --color-neutral-0: #ffffff;
  /* Semantic */
  --color-success: #15803d;
  --color-warning: #b45309;
  --color-error: #b91c1c;
  --color-info: #1a6fb5;

  /* Typography */
  --font-heading: "Poppins", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-body: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
  --text-display: 3rem;
  --text-h1: 2.25rem;
  --text-h2: 1.75rem;
  --text-h3: 1.375rem;
  --text-body-lg: 1.125rem;
  --text-body: 1rem;
  --text-small: 0.875rem;
  --text-xs: 0.75rem;

  /* Spacing (4-pt scale) */
  --space-0: 0;
  --space-4: 0.25rem;
  --space-8: 0.5rem;
  --space-12: 0.75rem;
  --space-16: 1rem;
  --space-24: 1.5rem;
  --space-32: 2rem;
  --space-48: 3rem;
  --space-64: 4rem;
  --space-96: 6rem;

  /* Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;

  /* Elevation */
  --shadow-sm: 0 1px 2px rgba(6, 37, 68, 0.08), 0 1px 3px rgba(6, 37, 68, 0.06);
  --shadow-md: 0 4px 6px rgba(6, 37, 68, 0.08), 0 2px 4px rgba(6, 37, 68, 0.06);
  --shadow-lg: 0 12px 24px rgba(6, 37, 68, 0.14), 0 4px 8px rgba(6, 37, 68, 0.08);

  /* Containers */
  --container-prose: 720px;
  --container-content: 1080px;
  --container-wide: 1280px;

  /* Focus ring (WCAG 2.2 — visible, >=3:1) */
  --focus-ring: 0 0 0 2px var(--color-neutral-0), 0 0 0 4px var(--color-primary-500);
}

/* ---- Reset & base ------------------------------------------------------ */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--text-body);
  line-height: 1.6;
  color: var(--color-neutral-900);
  background: var(--color-neutral-0);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, h4 { font-family: var(--font-heading); line-height: 1.2; margin: 0 0 var(--space-16); color: var(--color-primary-900); }
h1 { font-size: var(--text-h1); }
h2 { font-size: var(--text-h2); }
h3 { font-size: var(--text-h3); }
p { margin: 0 0 var(--space-16); max-width: 70ch; }
a { color: var(--color-primary-700); text-decoration: underline; text-underline-offset: 2px; }
a:hover { color: var(--color-primary-500); }
img { max-width: 100%; height: auto; display: block; }

/* ---- Accessibility: focus & skip link ---------------------------------- */
:focus-visible { outline: none; box-shadow: var(--focus-ring); border-radius: var(--radius-sm); }

.skip-link {
  position: absolute;
  left: var(--space-8);
  top: -64px;
  z-index: 1000;
  padding: var(--space-8) var(--space-16);
  background: var(--color-primary-700);
  color: #fff;
  border-radius: var(--radius-md);
  transition: top 0.15s ease;
}
.skip-link:focus { top: var(--space-8); color: #fff; }

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

/* ---- Layout ------------------------------------------------------------ */
.container { width: 100%; max-width: var(--container-content); margin-inline: auto; padding-inline: var(--space-16); }
.container--prose { max-width: var(--container-prose); }
.container--wide { max-width: var(--container-wide); }
main { flex: 1 0 auto; }
.section { padding-block: var(--space-48); }
.stack > * + * { margin-top: var(--space-16); }
.grid { display: grid; gap: var(--space-24); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }
.grid--2 { grid-template-columns: repeat(2, 1fr); }

/* ---- Buttons ----------------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-8);
  min-height: 44px; min-width: 44px; padding: var(--space-12) var(--space-24);
  font-family: var(--font-body); font-size: var(--text-body); font-weight: 600;
  border: 1px solid transparent; border-radius: var(--radius-md);
  cursor: pointer; text-decoration: none; transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.btn:disabled, .btn[aria-disabled="true"] { opacity: 0.5; cursor: not-allowed; }
.btn--primary { background: var(--color-primary-700); color: #fff; }
.btn--primary:hover { background: var(--color-primary-500); color: #fff; }
.btn--secondary { background: transparent; color: var(--color-primary-700); border-color: var(--color-primary-700); }
.btn--secondary:hover { background: var(--color-primary-100); }
.btn--tertiary { background: transparent; color: var(--color-primary-700); padding-inline: var(--space-12); }
.btn--tertiary:hover { background: var(--color-neutral-100); }
.btn--destructive { background: var(--color-error); color: #fff; }
.btn--destructive:hover { filter: brightness(1.08); }
.btn--icon { padding: var(--space-12); }
.btn--sm { min-height: 36px; padding: var(--space-8) var(--space-16); font-size: var(--text-small); }

/* ---- Forms ------------------------------------------------------------- */
.field { margin-bottom: var(--space-24); }
.field__label { display: block; font-weight: 600; margin-bottom: var(--space-8); color: var(--color-neutral-900); }
.field__req { color: var(--color-error); }
.field__help { font-size: var(--text-small); color: var(--color-neutral-500); margin-top: var(--space-4); }
.field__error { font-size: var(--text-small); color: var(--color-error); margin-top: var(--space-4); display: flex; gap: var(--space-4); align-items: center; }
.input, .select, .textarea {
  width: 100%; min-height: 44px; padding: var(--space-12) var(--space-16);
  font: inherit; color: var(--color-neutral-900);
  background: var(--color-neutral-0);
  border: 1px solid var(--color-neutral-300); border-radius: var(--radius-md);
}
.textarea { min-height: 120px; }
.input::placeholder { color: var(--color-neutral-500); }
.input[aria-invalid="true"], .select[aria-invalid="true"], .textarea[aria-invalid="true"] {
  border-color: var(--color-error); box-shadow: 0 0 0 1px var(--color-error);
}

/* ---- Tables ------------------------------------------------------------ */
.table { width: 100%; border-collapse: collapse; font-size: var(--text-body); }
.table caption { text-align: left; font-weight: 600; padding-bottom: var(--space-8); }
.table th, .table td { text-align: left; padding: var(--space-12) var(--space-16); border-bottom: 1px solid var(--color-neutral-300); }
.table thead th { position: sticky; top: 0; background: var(--color-neutral-100); color: var(--color-neutral-700); }
.table tbody tr:nth-child(even) { background: var(--color-neutral-100); }
.table td.num, .table th.num { text-align: right; font-variant-numeric: tabular-nums; }

/* ---- Cards ------------------------------------------------------------- */
.card { background: var(--color-neutral-0); border: 1px solid var(--color-neutral-300); border-radius: var(--radius-lg); box-shadow: var(--shadow-sm); overflow: hidden; }
.card__header { padding: var(--space-16) var(--space-24); border-bottom: 1px solid var(--color-neutral-100); }
.card__header h3 { margin: 0; }
.card__body { padding: var(--space-24); }
.card__footer { padding: var(--space-16) var(--space-24); border-top: 1px solid var(--color-neutral-100); background: var(--color-neutral-100); }

/* ---- Alerts ------------------------------------------------------------ */
.alert { display: flex; gap: var(--space-12); padding: var(--space-16); border-radius: var(--radius-md); border: 1px solid; }
.alert--success { background: #ecfdf3; border-color: var(--color-success); color: #0f5132; }
.alert--warning { background: #fff7ed; border-color: var(--color-warning); color: #7c3a00; }
.alert--error { background: #fef2f2; border-color: var(--color-error); color: #7f1d1d; }
.alert--info { background: var(--color-primary-100); border-color: var(--color-info); color: var(--color-primary-900); }

/* ---- Badges ------------------------------------------------------------ */
.badge { display: inline-flex; align-items: center; gap: var(--space-4); padding: var(--space-4) var(--space-12); font-size: var(--text-xs); font-weight: 600; border-radius: var(--radius-full); background: var(--color-neutral-100); color: var(--color-neutral-700); }
.badge--success { background: #ecfdf3; color: #0f5132; }
.badge--warning { background: #fff7ed; color: #7c3a00; }
.badge--error { background: #fef2f2; color: #7f1d1d; }
.badge--info { background: var(--color-primary-100); color: var(--color-primary-900); }

/* ---- Breadcrumb -------------------------------------------------------- */
.breadcrumb { font-size: var(--text-small); color: var(--color-neutral-500); }
.breadcrumb ol { list-style: none; display: flex; flex-wrap: wrap; gap: var(--space-8); margin: 0; padding: 0; }
.breadcrumb li + li::before { content: "/"; margin-right: var(--space-8); color: var(--color-neutral-300); }

/* ---- Empty state ------------------------------------------------------- */
.empty-state { text-align: center; padding: var(--space-48) var(--space-24); color: var(--color-neutral-500); }
.empty-state__icon { font-size: 2.5rem; margin-bottom: var(--space-16); }
.empty-state p { margin-inline: auto; }

/* ---- Skeleton ---------------------------------------------------------- */
.skeleton { background: linear-gradient(90deg, var(--color-neutral-100) 25%, #e9edf3 37%, var(--color-neutral-100) 63%); background-size: 400% 100%; border-radius: var(--radius-md); animation: skeleton 1.4s ease infinite; }
.skeleton--text { height: 0.9rem; margin-bottom: var(--space-8); }
.skeleton--title { height: 1.5rem; width: 60%; margin-bottom: var(--space-16); }
@keyframes skeleton { 0% { background-position: 100% 0; } 100% { background-position: 0 0; } }

/* ---- Modal ------------------------------------------------------------- */
.modal[hidden] { display: none; }
.modal { position: fixed; inset: 0; z-index: 900; display: flex; align-items: center; justify-content: center; padding: var(--space-16); }
.modal__overlay { position: absolute; inset: 0; background: rgba(6, 37, 68, 0.55); }
.modal__dialog { position: relative; background: #fff; border-radius: var(--radius-lg); box-shadow: var(--shadow-lg); max-width: 480px; width: 100%; padding: var(--space-24); }
.modal__actions { margin-top: var(--space-24); display: flex; gap: var(--space-8); justify-content: flex-end; }

/* ---- Navigation: public ------------------------------------------------ */
.navbar { position: sticky; top: 0; z-index: 100; background: var(--color-neutral-0); border-bottom: 1px solid var(--color-neutral-300); }
.navbar__inner { display: flex; align-items: center; gap: var(--space-16); min-height: 64px; }
.navbar__brand { display: flex; align-items: center; gap: var(--space-8); font-family: var(--font-heading); font-weight: 700; color: var(--color-primary-900); text-decoration: none; }
.navbar__links { display: flex; gap: var(--space-8); list-style: none; margin: 0; padding: 0; }
.navbar__links a { display: inline-block; padding: var(--space-8) var(--space-12); border-radius: var(--radius-md); text-decoration: none; color: var(--color-neutral-700); }
.navbar__links a[aria-current="page"] { color: var(--color-primary-700); font-weight: 600; }
.navbar__cta { margin-left: auto; display: flex; gap: var(--space-8); align-items: center; }
.navbar__toggle { display: none; }

/* ---- Navigation: admin sidebar layout ---------------------------------- */
.admin-layout { display: flex; min-height: calc(100vh - 0px); width: 100%; }
.sidebar { width: 256px; flex-shrink: 0; background: var(--color-primary-900); color: #fff; padding: var(--space-16); }
.sidebar__brand { font-family: var(--font-heading); font-weight: 700; padding: var(--space-8); margin-bottom: var(--space-16); }
.sidebar nav ul { list-style: none; margin: 0; padding: 0; }
.sidebar a { display: block; padding: var(--space-12); border-radius: var(--radius-md); color: #cdd9e7; text-decoration: none; }
.sidebar a:hover, .sidebar a[aria-current="page"] { background: rgba(255, 255, 255, 0.1); color: #fff; }
.admin-main { flex: 1; min-width: 0; padding: var(--space-24); background: var(--color-neutral-100); }

/* ---- Mobile drawer ----------------------------------------------------- */
.drawer { position: fixed; inset: 0; z-index: 200; visibility: hidden; }
.drawer.is-open { visibility: visible; }
.drawer__overlay { position: absolute; inset: 0; background: rgba(6, 37, 68, 0.5); opacity: 0; transition: opacity 0.2s; }
.drawer.is-open .drawer__overlay { opacity: 1; }
.drawer__panel { position: absolute; inset-block: 0; inset-inline-start: 0; width: min(320px, 85vw); background: #fff; padding: var(--space-24); transform: translateX(-100%); transition: transform 0.2s ease; display: flex; flex-direction: column; gap: var(--space-8); overflow-y: auto; }
.drawer.is-open .drawer__panel { transform: translateX(0); }
.drawer a { padding: var(--space-12); border-radius: var(--radius-md); text-decoration: none; color: var(--color-neutral-900); }
.drawer a:hover { background: var(--color-neutral-100); }

/* ---- Mobile bottom navigation ----------------------------------------- */
.bottom-nav { position: fixed; inset-inline: 0; bottom: 0; z-index: 150; display: none; background: var(--color-neutral-0); border-top: 1px solid var(--color-neutral-300); }
.bottom-nav ul { display: flex; justify-content: space-around; list-style: none; margin: 0; padding: 0; }
.bottom-nav a { display: flex; flex-direction: column; align-items: center; gap: 2px; padding: var(--space-8); min-width: 44px; min-height: 44px; font-size: var(--text-xs); color: var(--color-neutral-500); text-decoration: none; }
.bottom-nav a[aria-current="page"] { color: var(--color-primary-700); }

/* ---- Hero -------------------------------------------------------------- */
.hero { background: linear-gradient(135deg, var(--color-primary-900), var(--color-primary-700)); color: #fff; padding-block: var(--space-96); }
.hero h1 { color: #fff; font-size: var(--text-display); }
.hero p { color: #dbe7f3; font-size: var(--text-body-lg); }

/* ---- Footer ------------------------------------------------------------ */
.footer { background: var(--color-primary-900); color: #c9d6e5; padding-block: var(--space-48); margin-top: var(--space-48); }
.footer a { color: #c9d6e5; }
.footer a:hover { color: #fff; }
.footer__cols { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-32); }
.footer__bottom { margin-top: var(--space-32); padding-top: var(--space-16); border-top: 1px solid rgba(255, 255, 255, 0.15); font-size: var(--text-small); }

/* ---- Utilities --------------------------------------------------------- */
.u-desktop { display: initial; }
.u-mobile { display: none; }
.swatch { height: 56px; border-radius: var(--radius-md); border: 1px solid var(--color-neutral-300); }

/* ---- Responsive (mobile-first breakpoints from docs/design) ------------ */
@media (max-width: 1023px) {
  .navbar__links { display: none; }
  .navbar__toggle { display: inline-flex; }
  .sidebar { display: none; }
  .grid--3, .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .footer__cols { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 767px) {
  .grid--2, .grid--3, .grid--4 { grid-template-columns: 1fr; }
  .footer__cols { grid-template-columns: 1fr; }
  .bottom-nav { display: block; }
  .has-bottom-nav main { padding-bottom: 72px; }
  .u-desktop { display: none; }
  .u-mobile { display: initial; }
  /* Responsive tables -> stacked cards */
  .table--responsive thead { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
  .table--responsive tr { display: block; border: 1px solid var(--color-neutral-300); border-radius: var(--radius-md); margin-bottom: var(--space-16); padding: var(--space-8); }
  .table--responsive td { display: flex; justify-content: space-between; gap: var(--space-16); border: none; padding: var(--space-8); }
  .table--responsive td::before { content: attr(data-label); font-weight: 600; color: var(--color-neutral-700); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; }
}

/* ==========================================================================
   Mission 11 — public website page blocks & utilities
   (Reusable classes so public pages need no inline CSS or duplicate styling.)
   ========================================================================== */

/* Page header (non-hero pages) */
.page-header { background: var(--color-primary-100); padding-block: var(--space-32); border-bottom: 1px solid var(--color-neutral-300); }
.page-header h1 { margin-bottom: var(--space-8); }
.page-header__subtitle { color: var(--color-neutral-700); font-size: var(--text-body-lg); margin: 0; max-width: 70ch; }

/* Text & spacing utilities */
.lead { font-size: var(--text-body-lg); color: var(--color-neutral-700); }
.muted { color: var(--color-neutral-500); }
.text-center { text-align: center; }
.mx-auto { margin-inline: auto; }
.mt-16 { margin-top: var(--space-16); }
.mt-24 { margin-top: var(--space-24); }
.mt-32 { margin-top: var(--space-32); }
.cluster { display: flex; flex-wrap: wrap; gap: var(--space-12); align-items: center; }
.cluster--center { justify-content: center; }
.prose { max-width: var(--container-prose); }
.prose h2 { margin-top: var(--space-32); }
.prose ul { padding-left: var(--space-24); }

.section--muted { background: var(--color-neutral-100); }

/* Stats */
.stat__num { font-size: var(--text-h2); font-family: var(--font-heading); color: var(--color-primary-700); display: block; }

/* Call-to-action band */
.cta-band { background: var(--color-primary-700); color: #fff; border-radius: var(--radius-lg); padding: var(--space-48); text-align: center; }
.cta-band h2 { color: #fff; }
.cta-band p { color: #dbe7f3; margin-inline: auto; }

/* Timeline */
.timeline { list-style: none; margin: 0; padding: 0; border-left: 2px solid var(--color-primary-100); }
.timeline__item { position: relative; padding: 0 0 var(--space-32) var(--space-32); }
.timeline__item::before { content: ""; position: absolute; left: -7px; top: 4px; width: 12px; height: 12px; border-radius: var(--radius-full); background: var(--color-accent-500); }
.timeline__year { font-family: var(--font-heading); font-weight: 700; color: var(--color-primary-700); }

/* Gallery */
.gallery-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-12); }
.gallery-item { display: block; border: 1px solid var(--color-neutral-300); padding: 0; background: none; border-radius: var(--radius-md); overflow: hidden; cursor: pointer; }
.gallery-item img { display: block; width: 100%; aspect-ratio: 4 / 3; object-fit: cover; }
.filter-chips { display: flex; flex-wrap: wrap; gap: var(--space-8); list-style: none; padding: 0; margin: 0 0 var(--space-24); }
.chip { display: inline-flex; min-height: 36px; align-items: center; padding: var(--space-8) var(--space-16); border-radius: var(--radius-full); border: 1px solid var(--color-neutral-300); background: #fff; cursor: pointer; font: inherit; color: var(--color-neutral-700); }
.chip[aria-pressed="true"] { background: var(--color-primary-700); color: #fff; border-color: var(--color-primary-700); }

/* Contact */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-32); }

/* FAQ accordion (native <details>) */
.accordion details { border: 1px solid var(--color-neutral-300); border-radius: var(--radius-md); padding: var(--space-16); margin-bottom: var(--space-12); }
.accordion summary { font-weight: 600; cursor: pointer; }
.accordion summary:focus-visible { box-shadow: var(--focus-ring); border-radius: var(--radius-sm); }

/* Drawer & footer helpers (replace former inline styles) */
.drawer__divider { width: 100%; border: none; border-top: 1px solid var(--color-neutral-300); margin-block: var(--space-8); }
.drawer__close { align-self: flex-end; }
.footer__list { list-style: none; padding: 0; margin: var(--space-8) 0 0; }
.footer__social { margin-top: var(--space-16); display: flex; gap: var(--space-12); }
.footer p { color: inherit; }

@media (max-width: 1023px) {
  .gallery-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 767px) {
  .gallery-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
}