/* ============================================================
   QPN Catalyst — qpncatalyst.io
   Legal-grade static site. Design optimized for enforceability:
   conspicuous notice, uncluttered layout, clear hierarchy.
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Fraunces:ital,opsz,wght@0,9..144,300;0,9..144,400;0,9..144,500;0,9..144,600;0,9..144,700;1,9..144,400&family=Plus+Jakarta+Sans:wght@400;500;600&display=swap');

/* --- Design Tokens --- */
:root {
  --font-heading: 'Fraunces', 'Georgia', serif;
  --font-body: 'Plus Jakarta Sans', system-ui, sans-serif;

  --color-ink: #0F172A;
  --color-ink-secondary: #3B4563;
  --color-ink-muted: #64748B;
  --color-paper: #FFFBF5;
  --color-paper-alt: #F5F0E8;

  --color-notice-bg: #FEF3C7;
  --color-notice-border: #D97706;
  --color-notice-text: #78350F;

  --color-callout-bg: #EFF6FF;
  --color-callout-border: #3B82F6;
  --color-callout-text: #1E3A5F;

  --color-accent: #2563eb;
  --color-accent-hover: #1d4ed8;

  --color-footer-bg: #0F172A;
  --color-footer-text: #94A3B8;
  --color-footer-link: #CBD5E1;

  --color-border: #E2DDD4;

  --max-width: 720px;
  --max-width-wide: 860px;
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;
}

/* --- Skip Link (accessibility) --- */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-sm);
  background: var(--color-accent);
  color: #fff;
  padding: var(--space-xs) var(--space-sm);
  border-radius: 0 0 4px 4px;
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
  z-index: 100;
}

.skip-link:focus {
  top: 0;
  color: #fff;
}

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

html {
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  color: var(--color-ink);
  background-color: var(--color-paper);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

a {
  color: var(--color-accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  transition: color 0.15s ease;
}

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

a:focus-visible,
.btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 2px;
}

/* --- Header --- */
.site-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-paper);
}

.site-header__inner {
  max-width: var(--max-width-wide);
  margin: 0 auto;
  padding: var(--space-sm) var(--space-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.site-header__logo {
  font-family: var(--font-heading);
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--color-ink);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.site-header__logo:hover {
  color: var(--color-ink);
}

.site-nav {
  display: flex;
  gap: var(--space-md);
}

.site-nav a {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--color-ink-secondary);
  text-decoration: none;
}

.site-nav a:hover {
  color: var(--color-ink);
}

/* --- Terms Notice Banner (every page, above the fold) --- */
.terms-notice {
  background: var(--color-notice-bg);
  border-bottom: 2px solid var(--color-notice-border);
  padding: var(--space-sm) var(--space-md);
}

.terms-notice__inner {
  max-width: var(--max-width-wide);
  margin: 0 auto;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-notice-text);
  line-height: 1.5;
}

.terms-notice__inner a {
  color: var(--color-notice-text);
  font-weight: 600;
  text-decoration-thickness: 2px;
}

/* --- Main Content --- */
.main-content {
  flex: 1;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-xl) var(--space-md) var(--space-xl);
  width: 100%;
}

/* --- Typography --- */
h1 {
  font-family: var(--font-heading);
  font-size: 2.4rem;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--color-ink);
  margin-bottom: var(--space-md);
}

h2 {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 500;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--color-ink);
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
}

h3 {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--color-ink);
  margin-top: var(--space-lg);
  margin-bottom: var(--space-xs);
}

p {
  margin-bottom: var(--space-sm);
  color: var(--color-ink-secondary);
}

.tagline {
  font-size: 1.15rem;
  color: var(--color-ink-secondary);
  margin-bottom: var(--space-lg);
  line-height: 1.6;
}

/* --- Callout Boxes --- */
.callout {
  border-left: 3px solid var(--color-callout-border);
  background: var(--color-callout-bg);
  padding: var(--space-md);
  margin: var(--space-lg) 0;
  border-radius: 0 4px 4px 0;
}

.callout p {
  color: var(--color-callout-text);
  margin-bottom: 0;
}

.callout p + p {
  margin-top: var(--space-xs);
}

/* Amber callout (for terms/notice emphasis) */
.callout--amber {
  border-left-color: var(--color-notice-border);
  background: var(--color-notice-bg);
}

.callout--amber p {
  color: var(--color-notice-text);
}

.callout--amber a {
  color: var(--color-notice-text);
  font-weight: 600;
}

/* --- Submit Gate Box --- */
.gate-box {
  border: 2px solid var(--color-border);
  padding: var(--space-lg);
  margin: var(--space-lg) 0;
  border-radius: 4px;
  text-align: center;
  background: var(--color-paper-alt);
}

.gate-box p {
  color: var(--color-ink-secondary);
}

/* --- Buttons --- */
.btn {
  display: inline-block;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  padding: 0.85rem 2rem;
  border-radius: 4px;
  transition: background-color 0.15s ease, transform 0.1s ease;
  cursor: pointer;
  border: none;
}

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

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

.btn--primary:hover {
  background: var(--color-accent-hover);
  color: #fff;
}

.btn--outline {
  background: transparent;
  color: var(--color-accent);
  border: 2px solid var(--color-accent);
}

.btn--outline:hover {
  background: var(--color-accent);
  color: #fff;
}

/* --- Terms Page Specifics --- */
.terms-header {
  text-align: center;
  padding-bottom: var(--space-md);
  margin-bottom: var(--space-lg);
  border-bottom: 1px solid var(--color-border);
}

.terms-header h1 {
  font-size: 1.8rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  font-weight: 700;
}

.terms-header .effective-date {
  font-size: 0.95rem;
  color: var(--color-ink-muted);
  margin-top: var(--space-xs);
  margin-bottom: 0;
}

.terms-body h2 {
  margin-top: var(--space-lg);
  font-size: 1.25rem;
}

.terms-body h3 {
  font-size: 1.05rem;
  margin-top: var(--space-md);
}

.terms-body p {
  color: var(--color-ink);
  font-size: 0.95rem;
  line-height: 1.75;
}

.terms-body ul, .terms-body ol {
  margin: var(--space-xs) 0 var(--space-sm) var(--space-md);
  color: var(--color-ink);
  font-size: 0.95rem;
  line-height: 1.75;
}

.terms-body li {
  margin-bottom: var(--space-xs);
}

.terms-signoff {
  margin-top: var(--space-xl);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.terms-signoff p {
  font-size: 0.9rem;
  color: var(--color-ink-muted);
}

/* Acceptance callout — extra emphasis */
.acceptance-callout {
  border: 2px solid var(--color-notice-border);
  background: var(--color-notice-bg);
  padding: var(--space-md) var(--space-md);
  margin: var(--space-lg) 0;
  border-radius: 4px;
}

.acceptance-callout p {
  color: var(--color-notice-text);
  font-weight: 500;
  font-size: 1rem;
  margin-bottom: 0;
}

/* --- Summary List --- */
.summary-list {
  list-style: none;
  padding: 0;
  margin: var(--space-sm) 0;
}

.summary-list li {
  padding: var(--space-xs) 0;
  padding-left: 1.2rem;
  position: relative;
  color: var(--color-ink-secondary);
  font-size: 0.95rem;
}

.summary-list li::before {
  content: "\2022";
  position: absolute;
  left: 0;
  color: var(--color-notice-border);
  font-weight: 700;
}

/* --- Step Cards (How It Works) --- */
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-md);
  margin-top: var(--space-md);
}

.step {
  background: var(--color-paper);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: var(--space-md);
}

.step-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: var(--space-xs);
}

.step-icon {
  display: block;
  flex-shrink: 0;
  width: 28px;
  height: 28px;
}

.step-num {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
  line-height: 1;
}

.step h3 {
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-ink);
  margin: 0 0 var(--space-xs);
}

.step p {
  font-size: 0.9rem;
  margin-bottom: 0;
}

/* --- Mode Cards (Response Modes) --- */
.modes {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-md);
  margin-top: var(--space-md);
}

.mode {
  background: var(--color-paper);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: var(--space-md);
}

.mode--default {
  border-color: var(--color-accent);
  background: var(--color-paper);
  border-width: 2px;
}

.mode-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: var(--space-xs);
}

.mode-icon {
  display: block;
  flex-shrink: 0;
  width: 28px;
  height: 28px;
}

.modes--axis {
  position: relative;
}

.modes--axis {
  grid-template-columns: repeat(3, 1fr);
}

.modes-axis {
  grid-column: 1 / -1;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-xs);
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

.mode h3 {
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-ink);
  margin: 0;
}

.mode p {
  font-size: 0.9rem;
  margin-bottom: 0;
}

.mode-tag {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  background: var(--color-accent);
  color: #fff;
  padding: 0.15rem 0.5rem;
  border-radius: 3px;
  margin-bottom: var(--space-xs);
}

/* --- Benefit Cards (Why Participate) --- */
.benefits {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-md);
  margin-top: var(--space-md);
}

.benefit {
  padding: var(--space-md);
  border: 1px solid var(--color-border);
  border-left: 1px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-paper);
}

.benefit h3 {
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-ink);
  margin: 0 0 var(--space-xs);
  margin-top: var(--space-xs);
}

.benefit p {
  font-size: 0.9rem;
  margin-bottom: 0;
}

.benefit-kicker {
  display: inline-block;
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
  line-height: 1;
}

.benefit-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-xs);
}

.benefit-icon {
  display: block;
  flex-shrink: 0;
  width: 28px;
  height: 28px;
}

/* --- Table of Contents --- */
.toc {
  border: 1px solid var(--color-border);
  background: var(--color-paper-alt);
  padding: var(--space-md) var(--space-lg);
  margin: var(--space-lg) 0;
  border-radius: 4px;
}

.toc__heading {
  font-weight: 600;
  margin: 0 0 var(--space-xs) 0;
  color: var(--color-ink-secondary);
  font-size: 0.95rem;
}

.toc ul {
  margin: 0;
  padding-left: var(--space-lg);
}

.toc li {
  margin-bottom: 0.15rem;
}

/* --- Section Divider --- */
.section-divider {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-md) 0;
}

.section-divider + h2 {
  margin-top: 0;
}

/* --- Guide Placeholder --- */
.placeholder-content {
  text-align: center;
  padding: var(--space-xl) 0;
}

.placeholder-content h1 {
  margin-bottom: var(--space-sm);
}

.placeholder-content p {
  font-size: 1.05rem;
}

/* --- Footer --- */
.site-footer {
  background: var(--color-footer-bg);
  padding: var(--space-md) var(--space-md);
  margin-top: auto;
}

.site-footer__inner {
  max-width: var(--max-width-wide);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.site-footer__copyright {
  font-size: 0.82rem;
  color: var(--color-footer-text);
}

.site-footer__links {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.site-footer__links a {
  font-size: 0.82rem;
  color: var(--color-footer-link);
  text-decoration: none;
}

.site-footer__links a:hover {
  color: #fff;
}

.site-footer__version {
  font-size: 0.75rem;
  color: var(--color-footer-text);
  opacity: 0.6;
}

/* --- Hamburger Toggle (CSS-only, hidden checkbox pattern) --- */
.nav-toggle {
  /* Visually hidden but kept in tab order so keyboard users can toggle the nav.
     Using the clip pattern instead of display:none preserves focusability. */
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
}

/* When the hidden checkbox receives keyboard focus, show a ring on the
   adjacent hamburger label so the user knows where focus is. */
.nav-toggle:focus-visible + .nav-hamburger {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.nav-hamburger {
  display: none;  /* hidden on desktop, shown via media query */
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  transition: background-color 0.15s ease;
  /* Position hamburger at far right of header */
  order: 2;
}

.nav-hamburger:hover {
  background-color: var(--color-paper-alt);
}

.nav-hamburger__bar {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-ink);
  border-radius: 1px;
  transition: transform 0.25s ease, opacity 0.2s ease;
}

/* Animate hamburger bars into X when toggle is checked */
.nav-toggle:checked ~ .nav-hamburger .nav-hamburger__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle:checked ~ .nav-hamburger .nav-hamburger__bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle:checked ~ .nav-hamburger .nav-hamburger__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* --- Responsive: Tablet / Narrow (768px) — Hamburger menu --- */
@media (max-width: 768px) {
  .nav-hamburger {
    display: flex;
  }

  .site-nav {
    /* Hidden by default on mobile */
    display: none;
    flex-direction: column;
    gap: var(--space-xs);
    width: 100%;
    order: 3;
    padding-top: var(--space-sm);
    border-top: 1px solid var(--color-border);
    margin-top: var(--space-xs);
  }

  .site-nav a {
    padding: var(--space-xs) 0;
    font-size: 1rem;
  }

  /* Show nav when hamburger is toggled */
  .nav-toggle:checked ~ .site-nav {
    display: flex;
  }

  .site-header__inner {
    flex-wrap: wrap;
  }

  .site-header__logo {
    order: 1;
    flex: 1;
  }

  /* Footer stacks at this breakpoint */
  .site-footer__inner {
    flex-direction: column;
    text-align: center;
  }

  .site-footer__links {
    flex-wrap: wrap;
    justify-content: center;
  }

  /* Cards stack to single column */
  .steps,
  .modes,
  .benefits {
    grid-template-columns: 1fr;
  }
}

/* --- Responsive: Mobile (640px) — Typography and spacing --- */
@media (max-width: 640px) {
  html {
    font-size: 16px;
  }

  h1 {
    font-size: 1.8rem;
  }

  h2 {
    font-size: 1.3rem;
  }

  .terms-header h1 {
    font-size: 1.4rem;
  }

  .gate-box {
    padding: var(--space-md);
  }

  .btn {
    width: 100%;
    text-align: center;
  }

  /* Ensure terms notice text wraps well on narrow screens */
  .terms-notice {
    padding: var(--space-xs) var(--space-sm);
  }

  .terms-notice__inner {
    font-size: 0.82rem;
    line-height: 1.6;
  }

  /* Prevent any element from causing horizontal overflow */
  .main-content {
    padding-left: var(--space-sm);
    padding-right: var(--space-sm);
    overflow-wrap: break-word;
    word-wrap: break-word;
  }

  .callout,
  .callout--amber,
  .acceptance-callout {
    padding: var(--space-sm);
  }
}

/* --- Responsive: Extra-narrow (480px) — hide Response Modes axis labels --- */
@media (max-width: 480px) {
  .modes-axis { display: none; }
}