/* ==========================================================================
   layout.css - page frame, header, sections, footer
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. Containers and section rhythm
   -------------------------------------------------------------------------- */

.shell {
  position: relative;
  z-index: 1;               /* above the paper grain */
}

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  padding-block: var(--space-2xl);
  border-top: 1px solid var(--rule);
}

.section--flush { border-top: none; }
.section--tight { padding-block: var(--space-xl); }

/* The header block of every section: number, kicker, title, lede. */
.section-head {
  display: grid;
  gap: var(--space-m);
  margin-bottom: var(--space-xl);
}

.section-head__meta {
  display: flex;
  align-items: center;
  gap: var(--space-s);
}

.section-head__meta::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--rule);
}

.section-head__title { max-width: 20ch; }

@media (min-width: 60rem) {
  .section-head--split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: end;
    column-gap: var(--space-xl);
  }
  .section-head--split .section-head__meta { grid-column: 1 / -1; }
}

/* Generic auto-fitting grid used by several sections */
.grid {
  display: grid;
  gap: var(--space-m);
}

.grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 22rem), 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 17rem), 1fr)); }

/* --------------------------------------------------------------------------
   2. Site header
   -------------------------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: blur(12px) saturate(140%);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur-fast) var(--ease-out),
              background-color var(--dur-fast) var(--ease-out);
}

.site-header[data-stuck="true"] { border-bottom-color: var(--rule); }

.site-header__inner {
  display: flex;
  align-items: center;
  gap: var(--space-m);
  min-height: 4.25rem;
}

/* Wordmark: a small chain glyph plus the name */
.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: -0.02em;
  font-size: var(--step-0);
  white-space: nowrap;
}

.wordmark__glyph {
  width: 1.5rem;
  height: 1.5rem;
  color: var(--accent);
  flex: none;
}

.wordmark__sub {
  color: var(--ink-faint);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

@media (max-width: 40rem) { .wordmark__sub { display: none; } }

.site-nav { margin-inline-start: auto; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(0.75rem, 1.8vw, 1.6rem);
}

.site-nav__link {
  position: relative;
  text-decoration: none;
  font-size: var(--step--1);
  font-weight: 500;
  color: var(--ink-soft);
  padding-block: 0.4rem;
  transition: color var(--dur-fast) var(--ease-out);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1.5px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur-mid) var(--ease-out);
}

.site-nav__link:hover { color: var(--ink); }
.site-nav__link:hover::after,
.site-nav__link[aria-current="true"]::after { transform: scaleX(1); }
.site-nav__link[aria-current="true"] { color: var(--ink); }

.site-header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  margin-inline-start: var(--space-m);
}

/* Mobile navigation ------------------------------------------------------- */

.nav-toggle { display: none; }

@media (max-width: 62rem) {
  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    border: 1px solid var(--rule);
    border-radius: var(--radius);
  }

  .nav-toggle__bars,
  .nav-toggle__bars::before,
  .nav-toggle__bars::after {
    content: "";
    display: block;
    width: 1.05rem;
    height: 1.5px;
    background: var(--ink);
    transition: transform var(--dur-mid) var(--ease-out),
                opacity var(--dur-fast) linear;
  }
  .nav-toggle__bars::before { transform: translateY(-5px); }
  .nav-toggle__bars::after  { transform: translateY(3.5px); }

  .nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
  .nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { transform: rotate(45deg); }
  .nav-toggle[aria-expanded="true"] .nav-toggle__bars::after  { transform: rotate(-45deg); }

  .site-nav {
    position: fixed;
    inset: 4.25rem 0 auto 0;
    background: var(--paper);
    border-block: 1px solid var(--rule);
    padding: var(--space-m) var(--gutter) var(--space-l);
    transform: translateY(-120%);
    visibility: hidden;
    transition: transform var(--dur-mid) var(--ease-out),
                visibility var(--dur-mid) linear;
  }

  .site-nav[data-open="true"] { transform: translateY(0); visibility: visible; }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__link {
    display: block;
    padding-block: var(--space-s);
    border-bottom: 1px solid var(--rule);
    font-size: var(--step-1);
    font-family: var(--font-display);
  }

  .site-nav__link::after { display: none; }
}

/* On the narrowest phones the header runs out of room. The "Connect" call to
   action is the first thing to go: the wallet section has its own button. */
/* Only shown once the header's own Connect button drops out. */
.site-nav__item--compact { display: none; }

@media (max-width: 30rem) {
  .site-nav__item--compact { display: block; }
  .site-header__inner { gap: var(--space-xs); }
  .site-header__actions { margin-inline-start: var(--space-xs); }
  .site-header__actions .btn--primary { display: none; }
  .icon-btn,
  .nav-toggle { width: 2.25rem; height: 2.25rem; }
}

/* --------------------------------------------------------------------------
   3. Reading-progress chain (fixed left rail, desktop only)
   -------------------------------------------------------------------------- */

.progress-rail {
  position: fixed;
  left: max(0.9rem, calc((100vw - var(--container)) / 2 - 2.6rem));
  top: 50%;
  transform: translateY(-50%);
  z-index: 90;
  display: none;
  flex-direction: column;
  align-items: center;
  gap: 0;
}

@media (min-width: 85rem) { .progress-rail { display: flex; } }

.progress-rail__link {
  display: grid;
  place-items: center;
  width: 1.6rem;
  height: 1.6rem;
  text-decoration: none;
}

.progress-rail__block {
  width: 0.55rem;
  height: 0.55rem;
  border: 1.5px solid var(--rule-strong);
  background: transparent;
  transform: rotate(45deg);
  transition: background-color var(--dur-mid) var(--ease-out),
              transform var(--dur-mid) var(--ease-out),
              border-color var(--dur-mid) var(--ease-out);
}

.progress-rail__link:hover .progress-rail__block { transform: rotate(45deg) scale(1.35); }

.progress-rail__link[aria-current="true"] .progress-rail__block {
  background: var(--accent);
  border-color: var(--accent);
  transform: rotate(45deg) scale(1.35);
}

.progress-rail__tether {
  width: 1.5px;
  height: 1.1rem;
  background: var(--rule);
}

/* --------------------------------------------------------------------------
   4. Footer
   -------------------------------------------------------------------------- */

.site-footer {
  border-top: 1px solid var(--rule);
  padding-block: var(--space-xl) var(--space-l);
  background: var(--paper-sunken);
}

.site-footer__grid {
  display: grid;
  gap: var(--space-l);
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 14rem), 1fr));
  margin-bottom: var(--space-xl);
}

.site-footer__col h4 { margin-bottom: var(--space-s); }

.link-list { display: grid; gap: var(--space-2xs); }

.link-list a {
  font-size: var(--step--1);
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  padding-block: 2px;
  transition: color var(--dur-fast) var(--ease-out),
              border-color var(--dur-fast) var(--ease-out);
}

.link-list a:hover { color: var(--accent); border-bottom-color: var(--accent); }

.link-list a[target="_blank"]::after {
  content: " ↗";
  color: var(--ink-faint);
  font-size: 0.85em;
}

.site-footer__baseline {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-s) var(--space-m);
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-m);
  border-top: 1px solid var(--rule);
  font-size: var(--step--1);
  color: var(--ink-faint);
}