/* Reset, type, page layout and the shared components:
   navigation, buttons, figure frame, code block, option switch, status tags. */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--ink-0);
  color: var(--text);
  font-family: var(--sans);
  font-size: var(--step-0);
  line-height: 1.6;
  font-stretch: 100%;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* The drafting grid behind the page. */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(24, 40, 110, 0.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(24, 40, 110, 0.045) 1px, transparent 1px);
  background-size: 40px 40px, 40px 40px;
  -webkit-mask-image: linear-gradient(180deg, #000 0, transparent 900px);
  mask-image: linear-gradient(180deg, #000 0, transparent 900px);
}

h1,
h2,
h3,
h4,
p,
ul,
ol,
dl,
dd,
figure,
pre {
  margin: 0;
}

ul,
ol {
  padding: 0;
  list-style: none;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration-color: var(--line-3);
  text-underline-offset: 0.22em;
  text-decoration-thickness: 1px;
  transition: color var(--fast), text-decoration-color var(--fast);
}

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

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

button {
  cursor: pointer;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 3px;
}

::selection {
  background: rgba(31, 68, 255, 0.2);
  color: var(--text);
}

[hidden] {
  display: none !important;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 100;
  padding: 10px 14px;
  background: var(--accent);
  color: #ffffff;
  border-radius: var(--r-1);
  font-weight: 600;
  text-decoration: none;
  transform: translateY(-200%);
}

.skip:focus {
  transform: none;
}

/* ---------- Type ---------- */

h1,
h2 {
  font-stretch: 112%;
  font-weight: 700;
  letter-spacing: -0.032em;
  line-height: 1;
  text-wrap: balance;
}

h1 {
  font-size: var(--step-4);
  line-height: 0.98;
}

h2 {
  font-size: var(--step-3);
}

h3 {
  font-size: var(--step-1);
  font-stretch: 106%;
  font-weight: 600;
  letter-spacing: -0.008em;
  line-height: 1.25;
}

h4 {
  font-size: var(--step-0);
  font-weight: 600;
  line-height: 1.3;
}

p {
  max-width: 64ch;
  text-wrap: pretty;
}

strong {
  font-weight: 620;
  color: var(--text);
}

code,
kbd,
pre,
.mono {
  font-family: var(--mono);
  font-stretch: 87.5%;
  font-size: 0.82em;
  font-weight: 400;
  letter-spacing: -0.01em;
}

:not(pre) > code {
  padding: 0.1em 0.38em;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: var(--ink-2);
  color: var(--text);
  white-space: nowrap;
}

.muted {
  color: var(--text-2);
}

.dim {
  color: var(--text-3);
}

/* ---------- Layout ---------- */

.wrap {
  width: min(100% - 2 * var(--gutter), var(--page));
  margin-inline: auto;
}

.sec {
  padding-block: var(--section);
  position: relative;
}

.sec__head {
  display: grid;
  gap: 28px;
  margin-bottom: clamp(40px, 6vw, 80px);
}

.sec__lead {
  display: grid;
  gap: 16px;
  color: var(--text-2);
  align-content: start;
}

.sec__lead p:first-child {
  color: var(--text);
  font-size: var(--step-1);
  line-height: 1.45;
}

@media (min-width: 960px) {
  .sec__head {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 64px;
    align-items: end;
  }
}

.prose {
  display: grid;
  gap: 16px;
  color: var(--text-2);
}

/* ---------- Navigation ---------- */

.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--nav-h);
  background: rgba(244, 245, 248, 0.82);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid transparent;
  transition: border-color var(--mid);
}

.nav[data-scrolled="true"] {
  border-bottom-color: var(--line);
}

.nav__inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav__brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-stretch: 112%;
  font-weight: 640;
  letter-spacing: -0.01em;
  text-decoration: none;
  white-space: nowrap;
}

.nav__brand:hover {
  color: var(--text);
}

.nav__mark {
  flex: none;
  width: 22px;
  height: 22px;
  color: var(--accent);
}

.nav__links {
  display: none;
  gap: 4px;
  margin-left: auto;
}

.nav__links a {
  padding: 8px 11px;
  white-space: nowrap;
  border-radius: var(--r-1);
  font-size: 0.92rem;
  color: var(--text-2);
  text-decoration: none;
}

.nav__links a:hover,
.nav__links a[aria-current="true"] {
  color: var(--text);
}

.nav__links a[aria-current="true"] {
  background: var(--ink-3);
}

.nav__cta {
  margin-left: auto;
}

.nav__toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line-2);
  border-radius: var(--r-1);
  background: transparent;
}

.nav__toggle svg {
  width: 18px;
  height: 18px;
}

.nav__progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  height: 1px;
  width: 100%;
  background: var(--accent);
  transform-origin: 0 50%;
  transform: scaleX(0);
}

.nav__sheet {
  position: fixed;
  inset: var(--nav-h) 0 auto 0;
  padding: 12px var(--gutter) 24px;
  background: var(--ink-1);
  border-bottom: 1px solid var(--line-2);
  box-shadow: var(--shadow);
  display: grid;
  gap: 2px;
}

.nav__sheet a {
  padding: 14px 4px;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  font-size: 1.05rem;
}

@media (min-width: 1200px) {
  .nav__links {
    display: flex;
  }

  .nav__cta {
    margin-left: 8px;
  }

  .nav__toggle,
  .nav__sheet {
    display: none;
  }
}

@media (max-width: 1199px) {
  .nav .nav__cta {
    display: none;
  }

  .nav__toggle {
    margin-left: auto;
  }
}

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 46px;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: var(--r-1);
  font-weight: 600;
  font-size: 0.97rem;
  letter-spacing: -0.005em;
  text-decoration: none;
  white-space: nowrap;
  transition: background var(--fast), border-color var(--fast), color var(--fast), transform var(--fast);
}

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

.btn svg {
  width: 18px;
  height: 18px;
  flex: none;
}

.btn--primary {
  background: var(--text);
  color: #ffffff;
}

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

.btn--line {
  border-color: var(--line-3);
  color: var(--text);
  background: var(--ink-1);
}

.btn--line:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn--small {
  min-height: 38px;
  padding: 0 14px;
  font-size: 0.9rem;
}

.btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- Figure frame ---------- */

.fig {
  position: relative;
  border: 1px solid var(--line-2);
  border-radius: var(--r-3);
  background: var(--ink-1);
  box-shadow: var(--shadow);
}

.fig__body {
  position: relative;
  padding: clamp(18px, 3vw, 40px);
}

.fig__cap {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  padding: 13px clamp(18px, 3vw, 40px);
  border-top: 1px solid var(--line);
  font-size: var(--step--1);
  color: var(--text-2);
}

.fig__no {
  font-family: var(--mono);
  font-stretch: 87.5%;
  font-size: var(--step--2);
  color: var(--text-3);
}

.fig__src {
  margin-left: auto;
  font-family: var(--mono);
  font-stretch: 87.5%;
  font-size: var(--step--2);
  color: var(--text-3);
}

/* ---------- Code ---------- */

.code {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--r-2);
  background: var(--ink-2);
  overflow: hidden;
}

.code__bar {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 38px;
  padding: 0 8px 0 14px;
  border-bottom: 1px solid var(--line);
  font-family: var(--mono);
  font-stretch: 87.5%;
  font-size: var(--step--2);
  color: var(--text-3);
}

.code__bar a {
  color: inherit;
}

.code__copy {
  margin-left: auto;
  padding: 5px 10px;
  border: 1px solid var(--line-2);
  border-radius: 5px;
  background: transparent;
  font-family: var(--sans);
  font-size: var(--step--2);
  color: var(--text-2);
}

.code__copy:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.code pre {
  padding: 16px 14px;
  overflow-x: auto;
  font-size: 0.76rem;
  line-height: 1.75;
  color: #1b2130;
  tab-size: 2;
}

.code pre .c {
  color: var(--text-3);
}

.code pre .k {
  color: var(--blue);
}

.code pre .s {
  color: var(--cyan);
}

.code pre .hl {
  display: inline-block;
  width: 100%;
  margin-inline: -14px;
  padding-inline: 12px 14px;
  border-left: 2px solid var(--accent);
  background: var(--blue-soft);
  color: var(--text);
}

.code pre .warn {
  color: var(--amber);
}

/* ---------- Option switch (a styled radio group) ---------- */

.switch {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 4px;
  padding: 4px;
  border: 1px solid var(--line-2);
  border-radius: var(--r-2);
  background: var(--ink-1);
}

.switch label {
  position: relative;
  display: inline-flex;
}

.switch input {
  position: absolute;
  inset: 0;
  opacity: 0;
  margin: 0;
  cursor: pointer;
}

.switch span {
  display: inline-flex;
  align-items: center;
  min-height: 36px;
  padding: 0 14px;
  border-radius: 7px;
  font-size: 0.9rem;
  font-weight: 540;
  color: var(--text-2);
  transition: background var(--fast), color var(--fast);
  white-space: nowrap;
}

.switch input:hover + span {
  color: var(--text);
}

.switch input:checked + span {
  background: var(--ink-3);
  color: var(--text);
  box-shadow: inset 0 0 0 1px var(--line-3);
}

.switch input:focus-visible + span {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ---------- Tags ---------- */

.tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 3px 9px;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  font-size: var(--step--2);
  font-weight: 560;
  line-height: 1.5;
  color: var(--text-2);
  white-space: nowrap;
}

.tag::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

.tag--trusted {
  color: var(--blue);
  border-color: rgba(31, 68, 255, 0.4);
}

.tag--enforced {
  color: var(--cyan);
  border-color: rgba(10, 143, 176, 0.45);
}

.tag--untrusted {
  color: var(--amber);
  border-color: rgba(217, 72, 15, 0.4);
}

.tag--plain::before {
  display: none;
}

/* ---------- Footer ---------- */

.foot {
  border-top: 1px solid var(--line);
  padding-block: 44px 56px;
  color: var(--text-3);
  font-size: var(--step--1);
}

.foot__grid {
  display: grid;
  gap: 28px;
}

.foot__links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
}

.foot__links a {
  color: var(--text-2);
}

.foot p {
  max-width: 70ch;
}

@media (min-width: 860px) {
  .foot__grid {
    grid-template-columns: 1fr auto;
    align-items: start;
  }
}

/* ---------- Motion preferences ---------- */

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

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-delay: 0ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    transition-delay: 0ms !important;
  }
}