/* ==========================================================================
   Components — buttons, header, nav, logo, timeline, footer, artifact block.
   All values come from assets/css/tokens.css. No gradients, no glass, no
   second accent. Forest Green only.
   ========================================================================== */

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-5);
  font-size: var(--text-body-sm);
  font-weight: var(--weight-medium);
  line-height: var(--leading-caption);
  border-radius: var(--radius-1);
  border: var(--border-hairline);
  white-space: nowrap;
  min-height: 44px;
  min-width: 44px;
  transition: background-color var(--motion-fast) var(--easing-standard),
    border-color var(--motion-fast) var(--easing-standard),
    color var(--motion-fast) var(--easing-standard),
    opacity var(--motion-fast) var(--easing-standard);
}

.btn--primary {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-paper);
}

.btn--primary:hover {
  background: var(--color-accent-strong);
  border-color: var(--color-accent-strong);
}

.btn--primary:focus-visible {
  outline-color: var(--color-focus);
}

.btn--secondary {
  background: transparent;
  border-color: var(--color-line);
  color: var(--color-ink);
}

.btn--secondary:hover {
  background: var(--color-paper-dim);
  border-color: var(--color-gray);
}

.btn--ghost {
  background: transparent;
  border-color: transparent;
  color: var(--color-ink-60);
}

.btn--ghost:hover {
  color: var(--color-ink);
}

.btn--sm {
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-caption);
}

.btn--lg {
  padding: var(--space-4) var(--space-7);
  font-size: var(--text-body);
}

@media (prefers-reduced-motion: reduce) {
  .btn {
    transition: none;
  }
}

/* ---- Site header ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-nav);
  height: var(--space-8);
  display: flex;
  align-items: center;
  border-bottom: var(--border-hairline);
  border-color: transparent;
  background: var(--color-paper);
  transition: border-color var(--motion-base) var(--easing-standard);
}

.site-header.is-condensed {
  border-color: var(--color-line);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
  width: 100%;
  padding-inline: var(--page-margin);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-sans);
  font-weight: var(--weight-semibold);
  font-size: var(--text-body);
  letter-spacing: var(--tracking-tight);
  color: var(--color-ink);
}

.logo__mark {
  width: var(--space-5);
  height: var(--space-5);
  border-radius: var(--radius-1);
  background: var(--color-accent);
}

/* ---- Nav ---- */
.nav {
  display: flex;
  align-items: center;
  gap: var(--space-7);
}

.nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.nav__link {
  position: relative;
  font-size: var(--text-body-sm);
  font-weight: var(--weight-medium);
  color: var(--color-ink-60);
  padding: var(--space-2) 0;
  transition: color var(--motion-fast) var(--easing-standard);
}

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

.nav__link[aria-current="true"]::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-accent);
  border-radius: var(--radius-full);
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

/* ---- Theme toggle ----
   Hidden until JS sets the `.js` class. No JS = light default only. */
.theme-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  background: transparent;
  border: var(--border-hairline);
  border-radius: var(--radius-1);
  color: var(--color-ink-60);
  transition: color var(--motion-fast) var(--easing-standard),
    border-color var(--motion-fast) var(--easing-standard),
    background-color var(--motion-fast) var(--easing-standard);
}

.js .theme-toggle {
  display: inline-flex;
}

.theme-toggle:hover {
  color: var(--color-ink);
  background: var(--color-paper-dim);
}

.theme-toggle__icon {
  display: none;
}

:root:not([data-theme="dark"]) .theme-toggle__icon--sun {
  display: block;
}

:root[data-theme="dark"] .theme-toggle__icon--moon {
  display: block;
}

/* ---- Mobile nav toggle ---- */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: transparent;
  border: var(--border-hairline);
  border-radius: var(--radius-1);
}

.nav-toggle__bar {
  width: 18px;
  height: 2px;
  margin-inline: auto;
  background: var(--color-ink);
  transition: transform var(--motion-fast) var(--easing-standard),
    opacity var(--motion-fast) var(--easing-standard);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

@media (max-width: 900px) {
  .nav-toggle {
    display: flex;
  }

  .nav {
    position: fixed;
    inset: var(--space-8) 0 0 0;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 0;
    padding: var(--space-6) var(--page-margin);
    background: var(--color-paper);
    border-top: var(--border-hairline);
    transform: translateY(-8px);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition: opacity var(--motion-base) var(--easing-standard),
      transform var(--motion-base) var(--easing-standard),
      visibility var(--motion-base) var(--easing-standard);
  }

  .nav.is-open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
  }

  .nav__list {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-2);
    width: 100%;
  }

  .nav__link {
    display: block;
    width: 100%;
    padding: var(--space-3) 0;
    font-size: var(--text-lead);
  }

  .nav__link[aria-current="true"]::after {
    display: none;
  }

  .nav__actions {
    margin-top: var(--space-6);
    width: 100%;
  }

  .nav__actions .btn {
    flex: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .site-header,
  .nav,
  .nav-toggle__bar,
  .theme-toggle,
  .nav__link {
    transition: none;
  }
}

/* ---- Eyebrow (small-caps label) ---- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-ink-60);
  margin-bottom: var(--space-4);
}

.eyebrow::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--color-accent-strong);
}

/* ---- Timeline ---- */
.timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-6) var(--space-5);
  counter-reset: step;
}

.timeline__step {
  position: relative;
  padding-top: var(--space-6);
  border-top: var(--border-hairline);
}

.timeline__step::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  position: absolute;
  top: calc(var(--space-3) * -1);
  left: 0;
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  color: var(--color-accent-strong);
  background: var(--color-paper);
  padding-inline-end: var(--space-3);
  line-height: var(--leading-caption);
}

.act--dim .timeline__step::before {
  background: var(--color-paper-dim);
}

.act--tinted .timeline__step::before {
  background: var(--color-accent-wash);
}

.timeline__title {
  font-size: var(--text-body);
  font-weight: var(--weight-medium);
  margin-bottom: var(--space-2);
  color: var(--color-ink);
}

.timeline__text {
  font-size: var(--text-body-sm);
  color: var(--color-ink-80);
}

@media (max-width: 900px) {
  .timeline {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 560px) {
  .timeline {
    grid-template-columns: 1fr;
  }
}

/* ---- Stat callout (real, countable facts only) ---- */
.stat {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-5);
  background: var(--color-accent-wash);
  border-radius: var(--radius-0);
}

.stat__value {
  font-size: var(--text-h3);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
  color: var(--color-accent-strong);
  font-variant-numeric: tabular-nums;
}

.stat__label {
  font-size: var(--text-caption);
  line-height: var(--leading-caption);
  color: var(--color-ink-60);
  max-width: 24ch;
}

/* ---- Artifact block (real or TODO placeholder) ---- */
.artifact {
  font-family: var(--font-mono);
  font-size: var(--text-body-sm);
  line-height: var(--leading-body);
  background: var(--color-paper-dim);
  border: var(--border-hairline);
  border-radius: var(--radius-0);
  padding: var(--space-5);
  overflow-x: auto;
}

/* On dim sections, lift the artifact to paper so it reads as the focal panel */
.act--dim .artifact {
  background: var(--color-paper);
  border-color: var(--color-gray);
  box-shadow: var(--elevation-1);
}

:root[data-theme="dark"] .act--dim .artifact {
  background: var(--color-accent-wash);
  border-color: var(--color-line);
}

.act--tinted .artifact {
  background: var(--color-paper);
  border-color: var(--color-line);
}

.artifact__caption {
  display: block;
  font-family: var(--font-sans);
  font-size: var(--text-caption);
  color: var(--color-ink-60);
  margin-bottom: var(--space-3);
}

.artifact pre {
  margin: 0;
  white-space: pre-wrap;
  word-break: break-word;
}

.artifact code {
  font-family: inherit;
  color: var(--color-ink);
}

/* ---- Footer ---- */
.site-footer {
  border-top: var(--border-hairline);
  padding-block: var(--space-9) var(--space-8);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, minmax(0, 1fr));
  gap: var(--space-8);
  margin-bottom: var(--space-9);
}

.footer-brand__text {
  margin-top: var(--space-4);
  max-width: var(--container-prose);
  font-size: var(--text-body-sm);
  color: var(--color-ink-80);
}

.footer-col__title {
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-ink-60);
  margin-bottom: var(--space-4);
}

.footer-col__list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer-col__list a {
  font-size: var(--text-body-sm);
  color: var(--color-ink-80);
  transition: color var(--motion-fast) var(--easing-standard);
}

.footer-col__list a:hover {
  color: var(--color-ink);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
  padding-top: var(--space-6);
  border-top: var(--border-hairline);
}

.footer-bottom__copy {
  font-size: var(--text-caption);
  color: var(--color-ink-60);
}

@media (max-width: 900px) {
  .footer-top {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 560px) {
  .footer-top {
    grid-template-columns: 1fr;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .footer-col__list a {
    transition: none;
  }
}

/* ---- Badge (quiet platform / stack labels) ---- */
.badge {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  line-height: var(--leading-caption);
  color: var(--color-ink-60);
  padding: var(--space-1) var(--space-2);
  background: var(--color-paper-dim);
  border-radius: var(--radius-1);
  white-space: nowrap;
}

.act--dark .badge {
  background: var(--color-paper-dim);
  color: var(--color-ink-60);
}

.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

/* ---- Case study card (proof card — one project unit) ---- */
.case-study-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-5);
}

@media (min-width: 768px) {
  .case-study-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-6);
  }
}

.case-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  padding: var(--space-5);
  background: var(--color-paper);
  border: var(--border-hairline);
  border-radius: var(--radius-2);
  border-left: 2px solid transparent;
  transition: background-color var(--motion-fast) var(--easing-standard),
    border-color var(--motion-fast) var(--easing-standard),
    box-shadow var(--motion-fast) var(--easing-standard);
}

.case-card:hover,
.case-card:focus-within {
  background: var(--color-accent-wash);
  border-left-color: var(--color-accent);
  box-shadow: var(--elevation-1);
}

.act--dim .case-card {
  background: var(--color-paper);
}

.act--dim .case-card:hover,
.act--dim .case-card:focus-within {
  background: var(--color-accent-wash);
}

.case-card__header {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.case-card__title {
  font-size: var(--text-h4);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
  color: var(--color-ink);
}

.case-card__industry {
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-ink-60);
}

.case-card__outcome {
  font-size: var(--text-body);
  font-weight: var(--weight-medium);
  color: var(--color-ink);
  line-height: var(--leading-body);
}

.case-card__details {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin: 0;
}

.case-card__details > div {
  display: grid;
  grid-template-columns: 5.5rem minmax(0, 1fr);
  gap: var(--space-3);
  align-items: baseline;
}

.case-card__details dt {
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-ink-60);
}

.case-card__details dd {
  margin: 0;
  font-size: var(--text-body-sm);
  color: var(--color-ink-80);
}

.case-card__link {
  margin-top: auto;
  padding-top: var(--space-2);
  font-size: var(--text-body-sm);
  font-weight: var(--weight-medium);
  color: var(--color-accent-strong);
  text-decoration: underline;
  text-underline-offset: 0.2em;
  align-self: flex-start;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  transition: color var(--motion-fast) var(--easing-standard);
}

.case-card__link:hover {
  color: var(--color-ink);
}

.case-card.is-hidden {
  display: none;
}

@media (max-width: 560px) {
  .case-card__details > div {
    grid-template-columns: 1fr;
    gap: var(--space-1);
  }

  .filter-bar {
    gap: var(--space-2);
  }

  .filter-btn {
    flex: 1 1 auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  .case-card,
  .case-card__link {
    transition: none;
  }
}

/* ---- Case study metadata (detail pages) ---- */
.case-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-5) var(--space-7);
  margin-top: var(--space-6);
  padding-top: var(--space-5);
  border-top: var(--border-hairline);
}

.case-meta__item {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  min-width: 8rem;
}

.case-meta__item dt {
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
  color: var(--color-ink-60);
}

.case-meta__item dd {
  margin: 0;
  font-size: var(--text-body-sm);
  font-weight: var(--weight-medium);
  color: var(--color-ink);
}

/* ---- Filter bar ---- */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-4);
  border-bottom: var(--border-hairline);
}

.filter-btn {
  padding: var(--space-2) var(--space-4);
  min-height: 44px;
  font-size: var(--text-caption);
  font-weight: var(--weight-medium);
  color: var(--color-ink-60);
  background: transparent;
  border: var(--border-hairline);
  border-radius: var(--radius-1);
  transition: color var(--motion-fast) var(--easing-standard),
    background-color var(--motion-fast) var(--easing-standard),
    border-color var(--motion-fast) var(--easing-standard);
}

.filter-btn:hover {
  color: var(--color-ink);
  background: var(--color-paper-dim);
}

.filter-btn.is-active {
  color: var(--color-accent-strong);
  border-color: var(--color-accent);
  background: var(--color-accent-wash);
}

.filter-status {
  font-size: var(--text-caption);
  color: var(--color-ink-60);
  margin-bottom: var(--space-4);
}

@media (prefers-reduced-motion: reduce) {
  .filter-btn {
    transition: none;
  }
}

/* ---- Stack group (quiet tech appendix on case studies) ---- */
.stack-groups {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-5);
}

@media (min-width: 768px) {
  .stack-groups {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-6);
  }
}

.stack-group {
  padding: var(--space-5);
  border: var(--border-hairline);
  border-radius: var(--radius-2);
  background: var(--color-paper);
}

.stack-group__title {
  font-size: var(--text-body);
  font-weight: var(--weight-medium);
  color: var(--color-ink);
  margin-bottom: var(--space-2);
}

.stack-group__desc {
  font-size: var(--text-body-sm);
  color: var(--color-ink-80);
  margin-bottom: var(--space-4);
}

.act--dim .stack-group {
  background: var(--color-paper);
}