/* Reset, typography, shared components (nav, buttons, tags, lists). */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + var(--space-4));
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--color-paper);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}

h1,
h2,
h3,
p,
ul,
ol,
dl,
dd,
figure,
blockquote,
fieldset {
  margin: 0;
  padding: 0;
}

ul,
ol {
  list-style: none;
}

fieldset {
  border: 0;
  min-width: 0;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

a {
  color: inherit;
}

button,
input,
select {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: var(--focus-ring);
  outline-offset: var(--focus-offset);
  border-radius: var(--radius-md);
}

::selection {
  background: var(--color-accent);
  color: var(--color-on-accent);
}

/* ---------- layout ---------- */

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

.section-head {
  display: grid;
  gap: var(--space-4);
  max-width: 46rem;
  margin-bottom: var(--space-12);
}

/* ---------- type ---------- */

.h-section {
  font-family: var(--font-display);
  font-size: var(--text-4xl);
  font-weight: var(--weight-display);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-display);
  text-wrap: balance;
}

.lead {
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: 1.5;
  color: var(--color-ink-2);
  text-wrap: pretty;
}

.eyebrow {
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-label);
  text-transform: uppercase;
  color: var(--color-brand-2);
}

.icon {
  width: 1.5em;
  height: 1.5em;
  flex: none;
  fill: currentColor;
}

/* ---------- skip link ---------- */

.skip-link {
  position: fixed;
  top: var(--space-2);
  left: var(--space-2);
  z-index: var(--z-skip);
  padding: var(--space-3) var(--space-5);
  border-radius: var(--radius-pill);
  background: var(--color-fill);
  color: var(--color-on-dark);
  font-weight: var(--weight-bold);
  text-decoration: none;
  transform: translateY(-200%);
  transition: transform var(--duration-fast) var(--ease-primary);
}

.skip-link:focus {
  transform: translateY(0);
}

/* ---------- brand ---------- */

.brand {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: var(--weight-display);
  letter-spacing: var(--tracking-heading);
  color: var(--color-brand);
  text-decoration: none;
  white-space: nowrap;
}

.brand__dot {
  color: var(--color-accent-strong);
}

.brand--xl {
  font-size: var(--text-4xl);
  line-height: 1;
  color: var(--color-on-dark);
}

.brand--xl .brand__dot {
  color: var(--color-accent);
}

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

.nav-sentinel {
  position: absolute;
  top: 0;
  left: 0;
  width: 1px;
  height: var(--space-6);
  pointer-events: none;
}

.nav {
  position: sticky;
  top: 0;
  z-index: var(--z-nav);
  height: var(--nav-h);
  background: var(--color-paper);
  border-bottom: 1px solid transparent;
  transition:
    border-color var(--duration-fast) var(--ease-primary),
    box-shadow var(--duration-fast) var(--ease-primary);
}

.nav.is-stuck {
  border-bottom-color: var(--color-line);
  box-shadow: var(--shadow-card);
}

.nav__inner {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  height: 100%;
}

.nav__links {
  display: flex;
  gap: var(--space-1);
  margin-inline: auto;
}

.nav__links a {
  display: inline-flex;
  align-items: center;
  min-height: var(--tap);
  padding-inline: var(--space-4);
  border-radius: var(--radius-pill);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  color: var(--color-ink-2);
  text-decoration: none;
  white-space: nowrap;
  transition:
    background-color var(--duration-micro) var(--ease-primary),
    color var(--duration-micro) var(--ease-primary);
}

.nav__links a.is-current {
  color: var(--color-brand);
  background: var(--color-tint);
}

.nav__links .nav__menu-cta,
.nav__links .nav__menu-lang {
  display: none;
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.text-size,
.theme-toggle,
.lang-switch,
.nav__toggle {
  display: inline-grid;
  place-items: center;
  width: var(--tap);
  height: var(--tap);
  padding: 0;
  border: var(--border);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  color: var(--color-brand);
  font-family: var(--font-display);
  font-weight: var(--weight-bold);
  cursor: pointer;
  transition:
    background-color var(--duration-micro) var(--ease-primary),
    border-color var(--duration-micro) var(--ease-primary),
    transform var(--duration-micro) var(--ease-primary);
}

.text-size[aria-pressed="true"] {
  background: var(--color-fill);
  border-color: var(--color-brand);
  color: var(--color-on-dark);
}

.text-size:active,
.theme-toggle:active,
.lang-switch:active,
.nav__toggle:active {
  transform: scale(0.97);
}

.lang-switch {
  font-size: var(--text-sm);
  text-decoration: none;
}

/* the control shows the theme it switches TO */
.theme-toggle .icon--sun,
:root[data-theme="dark"] .theme-toggle .icon--moon {
  display: none;
}

:root[data-theme="dark"] .theme-toggle .icon--sun {
  display: block;
}

.nav__toggle {
  display: none;
}

.nav__toggle .icon--close,
.nav.is-open .nav__toggle .icon--open {
  display: none;
}

.nav.is-open .nav__toggle .icon--close {
  display: block;
}

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  min-height: 3.5rem;
  padding: var(--space-3) var(--space-8);
  border: 2px solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-display);
  font-size: var(--text-base);
  font-weight: var(--weight-bold);
  line-height: 1.1;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition:
    background-color var(--duration-micro) var(--ease-primary),
    border-color var(--duration-micro) var(--ease-primary),
    color var(--duration-micro) var(--ease-primary),
    scale var(--duration-micro) var(--ease-primary);
}

.btn:active {
  scale: 0.97;
}

.btn .icon {
  width: 1.25em;
  height: 1.25em;
  transition: translate var(--duration-fast) var(--ease-primary);
}

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

.btn--ghost {
  border-color: var(--color-brand);
  color: var(--color-brand);
}

.btn--sm {
  min-height: var(--tap);
  padding-inline: var(--space-6);
}

.btn--block {
  width: 100%;
}

.btn[aria-busy="true"] {
  opacity: 0.7;
  pointer-events: none;
}

@media (hover: hover) and (pointer: fine) {
  .nav__links a:hover {
    background: var(--color-paper-2);
    color: var(--color-brand);
  }

  .text-size:hover,
  .theme-toggle:hover,
  .lang-switch:hover,
  .nav__toggle:hover {
    border-color: var(--color-brand);
  }

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

  .btn--ghost:hover {
    background: var(--color-fill);
    color: var(--color-on-dark);
  }

  .btn:hover .icon {
    translate: 0.25rem 0;
  }
}

/* ---------- tags and check lists ---------- */

.tag {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  min-height: 2rem;
  padding: var(--space-1) var(--space-4);
  border-radius: var(--radius-pill);
  background: var(--color-paper-2);
  color: var(--color-ink-2);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: var(--weight-bold);
}

.tag--accent {
  background: var(--color-accent);
  color: var(--color-on-accent);
}

.checks {
  display: grid;
  gap: var(--space-3);
}

.checks li {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  line-height: 1.4;
}

.checks .icon {
  margin-top: 0.05em;
  color: var(--color-accent);
}

.checks--dark .icon {
  color: var(--color-brand-2);
}

/* ---------- scroll reveal base state ---------- */

.has-motion [data-reveal]:not(.is-revealed) {
  opacity: 0;
}

/* ---------- mobile navigation ---------- */

@media (max-width: 74.99em) {
  .nav__toggle {
    display: inline-grid;
  }

  .nav__inner {
    gap: var(--space-4);
    justify-content: space-between;
  }

  .nav__links {
    position: fixed;
    inset: var(--nav-h) 0 0 0;
    z-index: var(--z-menu);
    flex-direction: column;
    gap: 0;
    margin: 0;
    padding: var(--space-6) var(--gutter) var(--space-12);
    background: var(--color-paper);
    overflow-y: auto;
    visibility: hidden;
    opacity: 0;
    transform: translateY(calc(var(--space-2) * -1));
    transition:
      opacity var(--duration-fast) var(--ease-primary),
      transform var(--duration-fast) var(--ease-primary),
      visibility 0s linear var(--duration-fast);
  }

  .nav.is-open .nav__links {
    visibility: visible;
    opacity: 1;
    transform: none;
    transition-delay: 0s;
  }

  .nav__links a {
    min-height: 4rem;
    padding-inline: 0;
    border-radius: 0;
    border-bottom: var(--border);
    font-family: var(--font-display);
    font-size: var(--text-xl);
    font-weight: var(--weight-bold);
    color: var(--color-brand);
  }

  .nav__links a.is-current {
    background: none;
  }

  .nav__links .nav__menu-lang {
    display: flex;
  }

  .lang-switch {
    display: none;
  }

  .nav__links .nav__menu-cta {
    display: flex;
    justify-content: center;
    margin-top: var(--space-8);
    border: 0;
    border-radius: var(--radius-pill);
    background: var(--color-accent);
    color: var(--color-on-accent);
    font-size: var(--text-base);
  }
}

@media (max-width: 34em) {
  .nav__cta {
    display: none;
  }
}

html.is-locked {
  overflow: hidden;
}

/* ---------- reduced motion ---------- */

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-property: opacity, background-color, border-color, color !important;
    animation-duration: var(--duration-fast) !important;
    animation-delay: 0ms !important;
  }
}

/* ---------- tight desktop header ---------- */

@media (min-width: 75em) and (max-width: 84.99em) {
  .nav__inner {
    gap: var(--space-4);
  }

  .nav__links {
    gap: 0;
  }

  .nav__links a {
    padding-inline: var(--space-3);
  }

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