/* ============================================================================
   FirmClock — Components: layout shell, navigation, buttons, forms, footer
   ========================================================================= */

/* --- Layout shell --------------------------------------------------------- */
.shell {
  width: 100%;
  max-width: var(--content-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.shell--wide { max-width: var(--wide-max); }

.section { padding-block: var(--section-y); position: relative; }
.section--ink {
  background: var(--ink-900);
  color: var(--fg-primary);
}
.section--sunken { background: var(--bg-sunken); }

.section__head {
  display: grid;
  gap: var(--s-5);
  max-width: 62ch;
}
.section__head--wide { max-width: none; }

.stack-4 { display: grid; gap: var(--s-4); }
.stack-6 { display: grid; gap: var(--s-6); }
.stack-8 { display: grid; gap: var(--s-8); }
.stack-12 { display: grid; gap: var(--s-12); }

/* ============================================================================
   Wordmark — temporary. Replaceable in one place.
   Structure: [mark] FirmClock. The mark is an interval bracket, not a clock face.
   ========================================================================= */
.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--fg-primary);
  font-family: var(--font-ui);
  font-size: 1.0625rem;
  font-weight: 560;
  letter-spacing: -0.022em;
  line-height: 1;
  white-space: nowrap;
}
.wordmark__mark {
  width: 18px;
  height: 18px;
  flex: none;
  color: var(--fg-accent);
}
.wordmark__mark svg { width: 100%; height: 100%; display: block; }
.wordmark__text em {
  font-style: normal;
  font-weight: 400;
  color: var(--fg-secondary);
}
.wordmark--lg { font-size: 1.375rem; gap: 0.7rem; }
.wordmark--lg .wordmark__mark { width: 23px; height: 23px; }

/* ============================================================================
   Navigation — refines and compacts on scroll
   ========================================================================= */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  background: color-mix(in srgb, var(--paper-050) 82%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition:
    background var(--dur-base) var(--ease-out),
    border-color var(--dur-base) var(--ease-out),
    box-shadow var(--dur-base) var(--ease-out);
}
.site-header__inner {
  display: flex;
  align-items: center;
  gap: var(--s-8);
  max-width: var(--wide-max);
  margin-inline: auto;
  padding: var(--s-5) var(--gutter);
  transition: padding var(--dur-base) var(--ease-out);
}
.site-header.is-compact {
  background: color-mix(in srgb, var(--paper-050) 93%, transparent);
  border-bottom-color: var(--line-hairline);
  box-shadow: 0 1px 20px -8px rgba(11, 19, 21, 0.16);
}
.site-header.is-compact .site-header__inner { padding-block: var(--s-3); }

/* A hairline measure runs beneath the header and fills with scroll progress. */
.site-header__progress {
  position: absolute;
  left: 0; bottom: -1px;
  height: 2px;
  width: 100%;
  transform: scaleX(var(--scroll-progress, 0));
  transform-origin: left center;
  background: var(--accent-500);
  opacity: 0;
  transition: opacity var(--dur-base) var(--ease-out);
}
.site-header.is-compact .site-header__progress { opacity: 1; }

.nav {
  display: flex;
  align-items: center;
  gap: var(--s-1);
  margin-inline-start: auto;
}
.nav__link {
  position: relative;
  padding: var(--s-2) var(--s-3);
  font-size: var(--fs-body-sm);
  font-weight: 450;
  color: var(--fg-secondary);
  border-radius: var(--r-sm);
  transition: color var(--dur-fast) var(--ease-out);
}
.nav__link::after {
  content: "";
  position: absolute;
  left: var(--s-3);
  right: var(--s-3);
  bottom: 2px;
  height: 1px;
  background: var(--fg-accent);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur-base) var(--ease-out);
}
.nav__link:hover { color: var(--fg-primary); }
.nav__link:hover::after,
.nav__link:focus-visible::after { transform: scaleX(1); }
.nav__link[aria-current="true"] { color: var(--fg-primary); }
.nav__link[aria-current="true"]::after { transform: scaleX(1); }

.nav__divider {
  width: 1px;
  height: 18px;
  background: var(--line-soft);
  margin-inline: var(--s-3);
}
.nav-actions { display: flex; align-items: center; gap: var(--s-2); }

/* --- Mobile navigation ---------------------------------------------------- */
.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px; height: 40px;
  margin-inline-start: auto;
  background: transparent;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-sm);
  cursor: pointer;
  color: var(--fg-primary);
}
.nav-toggle__bars { display: block; width: 16px; height: 10px; position: relative; }
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0; right: 0;
  height: 1.5px;
  background: currentColor;
  transition: transform var(--dur-base) var(--ease-out);
}
.nav-toggle__bars::before { top: 0; }
.nav-toggle__bars::after { bottom: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { transform: translateY(4.25px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { transform: translateY(-4.25px) rotate(-45deg); }

.mobile-nav {
  display: none;
  border-top: 1px solid var(--line-hairline);
  background: var(--paper-050);
  padding: var(--s-4) var(--gutter) var(--s-8);
}
.mobile-nav__list { display: grid; }
.mobile-nav__link {
  display: flex;
  align-items: baseline;
  gap: var(--s-4);
  padding: var(--s-4) 0;
  border-bottom: 1px solid var(--line-hairline);
  font-size: 1.125rem;
  font-weight: 450;
}
.mobile-nav__link .metric { font-size: var(--fs-micro); color: var(--fg-muted); }
.mobile-nav__actions { display: grid; gap: var(--s-3); margin-top: var(--s-6); }

/* ============================================================================
   Buttons
   ========================================================================= */
.btn {
  --btn-pad-y: 0.6875rem;
  --btn-pad-x: 1.125rem;
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--s-2);
  padding: var(--btn-pad-y) var(--btn-pad-x);
  font-size: var(--fs-body-sm);
  font-weight: 500;
  letter-spacing: -0.008em;
  line-height: 1.2;
  border: 1px solid transparent;
  border-radius: var(--r-md);
  cursor: pointer;
  white-space: nowrap;
  background: transparent;
  transition:
    background-color var(--dur-fast) var(--ease-out),
    border-color var(--dur-fast) var(--ease-out),
    color var(--dur-fast) var(--ease-out),
    transform var(--dur-fast) var(--ease-out),
    box-shadow var(--dur-fast) var(--ease-out);
}
.btn:active { transform: translateY(0.5px); }
.btn[disabled],
.btn[aria-disabled="true"] { cursor: not-allowed; opacity: 0.62; }

.btn--primary {
  background: var(--ink-900);
  color: var(--paper-050);
  box-shadow: var(--shadow-sm);
}
.btn--primary:hover { background: var(--ink-700); }
.on-ink .btn--primary { background: var(--paper-050); color: var(--ink-900); }
.on-ink .btn--primary:hover { background: var(--paper-000); }

.btn--accent {
  background: var(--accent-600);
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn--accent:hover { background: var(--accent-700); }

.btn--ghost {
  color: var(--fg-primary);
  border-color: var(--line-soft);
  background: color-mix(in srgb, var(--paper-000) 60%, transparent);
}
.btn--ghost:hover { border-color: var(--line-strong); background: var(--paper-000); }
.on-ink .btn--ghost { background: transparent; }
.on-ink .btn--ghost:hover { background: rgba(255, 255, 255, 0.06); }

.btn--quiet { color: var(--fg-secondary); padding-inline: var(--s-3); }
.btn--quiet:hover { color: var(--fg-primary); }

.btn--lg { --btn-pad-y: 0.875rem; --btn-pad-x: 1.5rem; font-size: var(--fs-body); }
.btn--block { width: 100%; }

/* The trailing rule: a two-tick measure that extends on hover. */
.btn__rule {
  display: inline-block;
  width: 14px;
  height: 7px;
  flex: none;
  border-left: 1px solid currentColor;
  border-right: 1px solid currentColor;
  border-bottom: 1px solid currentColor;
  opacity: 0.5;
  transition: width var(--dur-base) var(--ease-out), opacity var(--dur-base) var(--ease-out);
}
.btn:hover .btn__rule { width: 20px; opacity: 0.85; }

/* ============================================================================
   Cards & panels
   ========================================================================= */
.panel {
  background: var(--bg-raised);
  border: 1px solid var(--line-hairline);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-sm);
}
.on-ink .panel {
  background: var(--ink-850);
  border-color: var(--line-inverse-hairline);
  box-shadow: none;
}

.note {
  display: flex;
  gap: var(--s-3);
  align-items: flex-start;
  padding: var(--s-4) var(--s-5);
  border: 1px dashed var(--line-soft);
  border-radius: var(--r-md);
  background: color-mix(in srgb, var(--paper-100) 60%, transparent);
  font-size: var(--fs-body-sm);
  color: var(--fg-secondary);
  max-width: 68ch;
}
.on-ink .note { background: rgba(255, 255, 255, 0.03); }
.note__tag {
  flex: none;
  font-family: var(--font-metric);
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--fg-accent);
  padding-top: 0.18em;
}

/* Conceptual marker — applied to every non-functional product visual. */
.concept-tag {
  display: inline-flex;
  align-items: center;
  gap: var(--s-2);
  font-family: var(--font-metric);
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--fg-muted);
  background: color-mix(in srgb, var(--paper-100) 80%, transparent);
  border: 1px solid var(--line-hairline);
  border-radius: var(--r-xs);
  padding: 0.3rem 0.55rem;
}
.concept-tag::before {
  content: "";
  width: 6px; height: 6px;
  border: 1px solid var(--fg-muted);
  flex: none;
}
.on-ink .concept-tag {
  background: rgba(255, 255, 255, 0.05);
  border-color: var(--line-inverse-hairline);
}

/* ============================================================================
   Forms
   ========================================================================= */
.field { display: grid; gap: var(--s-2); }
.field__label {
  font-size: var(--fs-meta);
  font-weight: 500;
  color: var(--fg-secondary);
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--s-3);
}
.field__optional {
  font-family: var(--font-metric);
  font-size: var(--fs-micro);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--fg-muted);
}
.field__control {
  width: 100%;
  padding: 0.75rem 0.875rem;
  font-size: var(--fs-body-sm);
  color: var(--fg-primary);
  background: var(--bg-raised);
  border: 1px solid var(--line-soft);
  border-radius: var(--r-md);
  transition: border-color var(--dur-fast) var(--ease-out), box-shadow var(--dur-fast) var(--ease-out);
  appearance: none;
}
textarea.field__control { min-height: 6.5rem; resize: vertical; line-height: 1.55; }
select.field__control {
  background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='7' viewBox='0 0 10 7'%3E%3Cpath d='M1 1l4 4 4-4' fill='none' stroke='%23667A80' stroke-width='1.3'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.875rem center;
  padding-right: 2.25rem;
}
.field__control::placeholder { color: var(--ui-faint); }
.field__control:hover { border-color: var(--line-strong); }
.field__control:focus-visible {
  outline: none;
  border-color: var(--accent-500);
  box-shadow: 0 0 0 3px var(--accent-100);
}
.field__error {
  display: none;
  align-items: center;
  gap: var(--s-2);
  font-size: var(--fs-meta);
  color: var(--flag-600);
}
.field__error::before {
  content: "";
  width: 8px; height: 8px;
  flex: none;
  border-left: 1.5px solid currentColor;
  border-top: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
}
.field.is-invalid .field__control {
  border-color: var(--flag-500);
  background: color-mix(in srgb, var(--flag-100) 40%, var(--bg-raised));
}
.field.is-invalid .field__control:focus-visible { box-shadow: 0 0 0 3px var(--flag-100); }
.field.is-invalid .field__error { display: flex; }

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--s-5);
}
.form-grid > .field--full { grid-column: 1 / -1; }

.form-status {
  display: flex;
  gap: var(--s-3);
  align-items: flex-start;
  padding: var(--s-4) var(--s-5);
  border-radius: var(--r-md);
  font-size: var(--fs-body-sm);
  border: 1px solid transparent;
}
.form-status[hidden] { display: none; }
.form-status--success {
  background: var(--accent-050);
  border-color: var(--accent-200);
  color: var(--accent-800);
}
.form-status--error {
  background: var(--flag-100);
  border-color: var(--flag-300);
  color: var(--flag-600);
}
.form-status__mark { flex: none; margin-top: 0.28em; }

/* A quiet prototype control — this build has no backend by design. */
.state-preview {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--s-3);
  padding-top: var(--s-5);
  margin-top: var(--s-5);
  border-top: 1px dashed var(--line-soft);
  font-size: var(--fs-meta);
  color: var(--fg-muted);
}
.state-preview__group { display: flex; flex-wrap: wrap; gap: var(--s-2); min-width: 0; }
.state-preview__btn {
  font-family: var(--font-metric);
  font-size: var(--fs-micro);
  letter-spacing: 0.09em;
  text-transform: uppercase;
  padding: 0.32rem 0.6rem;
  border: 1px solid var(--line-soft);
  background: transparent;
  border-radius: var(--r-xs);
  color: var(--fg-secondary);
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out);
}
.state-preview__btn:hover { border-color: var(--line-strong); color: var(--fg-primary); }

/* Loading indicator: the measure fills, rather than a spinner. */
.btn.is-loading { color: transparent; pointer-events: none; }
.btn.is-loading .btn__rule { opacity: 0; }
.btn__loader {
  position: absolute;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  gap: 3px;
}
.btn.is-loading .btn__loader { display: flex; }
.btn__loader span {
  width: 2px;
  height: 12px;
  background: currentColor;
  color: var(--paper-050);
  opacity: 0.28;
  animation: tickFill 1.05s var(--ease-in-out) infinite;
}
.btn__loader span:nth-child(2) { animation-delay: 0.12s; }
.btn__loader span:nth-child(3) { animation-delay: 0.24s; }
.btn__loader span:nth-child(4) { animation-delay: 0.36s; }
.btn__loader span:nth-child(5) { animation-delay: 0.48s; }
@keyframes tickFill {
  0%, 100% { opacity: 0.24; transform: scaleY(0.6); }
  40% { opacity: 1; transform: scaleY(1); }
}
@media (prefers-reduced-motion: reduce) {
  .btn__loader span { animation: none; opacity: 0.75; }
}

/* ============================================================================
   Footer
   ========================================================================= */
.site-footer {
  background: var(--ink-900);
  color: var(--fg-primary);
  padding-block: var(--s-20) var(--s-10);
}
.site-footer__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) repeat(3, minmax(0, 1fr));
  gap: var(--s-12) var(--s-8);
}
.footer-col__title {
  font-family: var(--font-metric);
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--fg-muted);
  margin-bottom: var(--s-4);
}
.footer-col__list { display: grid; gap: var(--s-3); }
.footer-col__list a {
  font-size: var(--fs-body-sm);
  color: var(--fg-secondary);
  transition: color var(--dur-fast) var(--ease-out);
  display: inline-flex;
  align-items: baseline;
  gap: var(--s-2);
}
.footer-col__list a:hover { color: var(--fg-primary); }
.footer-col__list a[data-placeholder]::after {
  content: "Placeholder";
  font-family: var(--font-metric);
  font-size: 0.5625rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--fg-muted);
  border: 1px solid var(--line-soft);
  border-radius: 2px;
  padding: 0.1rem 0.3rem;
  line-height: 1.4;
}

.site-footer__base {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-4) var(--s-8);
  align-items: center;
  justify-content: space-between;
  margin-top: var(--s-16);
  padding-top: var(--s-6);
  border-top: 1px solid var(--line-inverse-hairline);
  font-size: var(--fs-meta);
  color: var(--fg-muted);
}
.site-footer__base p { max-width: 62ch; }
.kavrico {
  font-family: var(--font-metric);
  font-size: var(--fs-micro);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--fg-muted);
  display: inline-flex;
  align-items: center;
  gap: var(--s-2);
}
.kavrico::before {
  content: "";
  width: 14px; height: 1px;
  background: var(--line-inverse-soft);
}

/* The footer terminal: the measure closes with a full end cap. */
.footer-terminal {
  max-width: var(--wide-max);
  margin: 0 auto var(--s-16);
  padding-inline: var(--gutter);
}
.footer-terminal__rule {
  display: block;
  position: relative;
  height: 16px;
  background-image:
    repeating-linear-gradient(to right,
      var(--tick-color) 0 1px, transparent 1px var(--tick-gap)),
    repeating-linear-gradient(to right,
      var(--tick-major-color) 0 1px, transparent 1px calc(var(--tick-gap) * 4));
  background-size: 100% 6px, 100% 12px;
  background-position: left bottom, left bottom;
  background-repeat: repeat-x;
  border-bottom: 1px solid var(--line-inverse-soft);
}
.footer-terminal__rule::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: 2px;
  height: 22px;
  background: var(--accent-400);
}