/* Agent-Pilled AI Agents site. One stylesheet, system fonts, no scripts. */

:root {
  color-scheme: light dark;

  --paper: #f7f5f0;
  --surface: #efebe3;
  --card: #ffffff;
  --ink: #1c1b19;
  --muted: #5d5950;
  --rule: #dcd6ca;
  --rule-strong: #b9b1a3;
  --grid: #e9e4da;
  --accent: #a3401a;
  --accent-hover: #8a3514;
  --on-accent: #ffffff;
  --tint: #f6e4d9;
  --done: #2f6b3a;
  --inverse: #1c1b19;
  --on-inverse: #f7f5f0;
  --on-inverse-muted: #cfcac0;
  --focus: #1d5fc4;

  --sans:
    system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial,
    sans-serif;
  --mono:
    ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --gutter: clamp(1rem, 4vw, 2rem);
  --radius: 14px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #161513;
    --surface: #1b1a18;
    --card: #211f1c;
    --ink: #ebe7df;
    --muted: #a59f94;
    --rule: #34312c;
    --rule-strong: #57524a;
    --grid: #22201d;
    --accent: #ee9466;
    --accent-hover: #f4ab85;
    --on-accent: #161513;
    --tint: #33241b;
    --done: #8cc79a;
    --inverse: #ebe7df;
    --on-inverse: #161513;
    --on-inverse-muted: #4a463f;
    --focus: #8ab4f8;
  }
}

/* Base */

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

html {
  text-size-adjust: 100%;
}

@media (prefers-reduced-motion: no-preference) {
  html {
    scroll-behavior: smooth;
  }
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 1.0625rem / 1.6 var(--sans);
  overflow-wrap: break-word;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover {
  text-decoration-thickness: 2px;
}

:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
  border-radius: 4px;
}

code {
  font-family: var(--mono);
  font-size: 0.9em;
  white-space: nowrap;
}

h1,
h2,
h3 {
  text-wrap: balance;
}

p,
li {
  text-wrap: pretty;
}

[id] {
  scroll-margin-top: 5rem;
}

.container {
  max-width: calc(72rem + 2 * var(--gutter));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container-narrow {
  max-width: calc(46rem + 2 * var(--gutter));
}

.skip {
  position: absolute;
  z-index: 20;
  left: var(--gutter);
  top: -100%;
  padding: 0.5rem 0.75rem;
  background: var(--ink);
  color: var(--paper);
}

.skip:focus {
  top: 0.5rem;
}

.icon {
  width: 1.125em;
  height: 1.125em;
  flex: none;
}

/* Header */

.site-header {
  border-bottom: 1px solid var(--rule);
  background: var(--paper);
}

@media (min-width: 48rem) {
  .site-header {
    position: sticky;
    top: 0;
    z-index: 10;
  }
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  padding-block: 0.75rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--ink);
  font-weight: 750;
  font-size: 1.1875rem;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 1.25rem;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 0.9375rem;
}

.nav-list a {
  color: var(--muted);
  text-decoration: none;
}

.nav-list a:hover {
  color: var(--ink);
}

.nav-list .nav-github {
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--rule-strong);
  border-radius: 8px;
  color: var(--ink);
}

/* Hero */

.hero {
  position: relative;
  isolation: isolate;
  padding-block: clamp(4rem, 10vw, 7.5rem) clamp(3.5rem, 8vw, 6rem);
  border-bottom: 1px solid var(--rule);
  text-align: center;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 2.5rem 2.5rem;
  background-position: center top;
  mask-image: radial-gradient(
    ellipse 70% 80% at 50% 0%,
    #000 30%,
    transparent 75%
  );
}

.hero-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.3rem 0.85rem;
  border: 1px solid var(--rule-strong);
  border-radius: 999px;
  background: var(--card);
  color: var(--ink);
  font-size: 0.875rem;
  font-weight: 600;
  text-decoration: none;
}

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

.badge-dot {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--accent);
}

.hero h1 {
  max-width: 15ch;
  margin: 1.5rem 0 0;
  font-size: clamp(2.5rem, 1.2rem + 5.5vw, 4.75rem);
  font-weight: 800;
  line-height: 1.04;
  letter-spacing: -0.025em;
}

.lead {
  max-width: 38rem;
  margin: 1.5rem 0 0;
  color: var(--muted);
  font-size: clamp(1.125rem, 1rem + 0.5vw, 1.3125rem);
  line-height: 1.55;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 2.25rem;
}

.button {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.8rem 1.35rem;
  border: 1px solid transparent;
  border-radius: 10px;
  font-weight: 650;
  line-height: 1.2;
  text-decoration: none;
}

.button .icon {
  fill: currentcolor;
}

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

.button-primary:hover {
  background: var(--accent-hover);
}

.button-secondary {
  border-color: var(--rule-strong);
  background: var(--card);
  color: var(--ink);
}

.button-secondary:hover {
  border-color: var(--ink);
}

.hero-meta {
  margin: 1.25rem 0 0;
  color: var(--muted);
  font-size: 0.875rem;
}

/* Sections */

.section {
  padding-block: clamp(4rem, 9vw, 6.5rem);
}

.section-alt {
  border-block: 1px solid var(--rule);
  background: var(--surface);
}

.eyebrow {
  margin: 0;
  color: var(--accent);
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-align: center;
  text-transform: uppercase;
}

.section h2 {
  max-width: 24ch;
  margin: 0.5rem auto 0;
  font-size: clamp(1.875rem, 1.3rem + 2.2vw, 2.75rem);
  font-weight: 780;
  line-height: 1.1;
  letter-spacing: -0.025em;
  text-align: center;
}

.section-intro {
  max-width: 40rem;
  margin: 1rem auto 0;
  color: var(--muted);
  text-align: center;
}

.section-more {
  margin: 2rem 0 0;
  color: var(--muted);
  text-align: center;
}

/* How it works */

.flow {
  margin: 3.5rem 0 0;
}

.flow-steps {
  --flow-gap: 3rem;

  display: grid;
  gap: var(--flow-gap);
  max-width: 26rem;
  margin: 0 auto;
  padding: 0;
  list-style: none;
}

.flow-step {
  position: relative;
  padding: 1.25rem 1.25rem 1.375rem;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--card);
}

.flow-step > p {
  margin: 0;
}

.flow-actor {
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.flow-actor code {
  color: var(--accent);
  font-size: 0.9375rem;
  letter-spacing: 0;
  text-transform: none;
}

.flow-title {
  margin-top: 0.375rem;
  font-size: 1.1875rem;
  font-weight: 720;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.flow-text {
  margin-top: 0.375rem;
  color: var(--muted);
  font-size: 0.9375rem;
  line-height: 1.5;
}

.flow-bot {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px var(--tint);
}

.flow-step > .flow-identity {
  display: inline-block;
  margin-top: 0.875rem;
  padding: 0.125rem 0.6rem;
  border-radius: 999px;
  background: var(--tint);
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 650;
}

.flow-you {
  border-color: var(--inverse);
  background: var(--inverse);
  color: var(--on-inverse);
}

.flow-you > .flow-actor,
.flow-you > .flow-text {
  color: var(--on-inverse-muted);
}

.flow-step > .flow-loop {
  margin-top: 1rem;
  padding-left: 0.75rem;
  border-left: 2px dashed var(--accent);
  color: var(--muted);
  font-size: 0.875rem;
  line-height: 1.45;
}

.flow-arrow {
  position: absolute;
  left: 50%;
  top: 100%;
  width: 2px;
  height: var(--flow-gap);
  background: var(--accent);
  transform: translateX(-50%);
}

.flow-arrow::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 1px;
  width: 0.6rem;
  height: 0.6rem;
  border-right: 2px solid var(--accent);
  border-bottom: 2px solid var(--accent);
  transform: translateX(-50%) rotate(45deg);
}

.flow-gate .icon {
  position: absolute;
  left: 50%;
  top: 45%;
  width: 1.9rem;
  height: 1.9rem;
  padding: 0.3rem;
  border: 2px solid var(--accent);
  border-radius: 50%;
  background: var(--paper);
  fill: none;
  stroke: var(--accent);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  transform: translate(-50%, -50%);
}

.flow figcaption {
  max-width: 40rem;
  margin: 2.5rem auto 0;
  color: var(--muted);
  font-size: 0.9375rem;
  text-align: center;
}

@media (min-width: 64rem) {
  .flow-steps {
    --flow-gap: 3.5rem;

    grid-template-columns: repeat(4, 1fr);
    max-width: none;
    padding-bottom: 6.5rem;
  }

  .flow-arrow {
    left: 100%;
    top: 50%;
    width: var(--flow-gap);
    height: 2px;
    transform: translateY(-50%);
  }

  .flow-arrow::after {
    left: auto;
    right: 1px;
    bottom: auto;
    top: 50%;
    transform: translateY(-50%) rotate(-45deg);
  }

  .flow-gate .icon {
    left: 50%;
    top: 50%;
  }

  /* The loop runs under the cards, from the review back to the author. */
  .flow-step > .flow-loop {
    position: absolute;
    right: 50%;
    top: calc(100% + 0.75rem);
    width: calc(100% + var(--flow-gap));
    height: 2.25rem;
    margin: 0;
    padding: 0;
    border: 2px dashed var(--accent);
    border-top: 0;
    border-radius: 0 0 1rem 1rem;
  }

  .flow-loop::before {
    content: "";
    position: absolute;
    left: -0.4rem;
    top: -0.1rem;
    width: 0.6rem;
    height: 0.6rem;
    border-right: 2px solid var(--accent);
    border-bottom: 2px solid var(--accent);
    transform: rotate(-135deg);
  }

  .flow-loop span {
    position: absolute;
    left: 0;
    right: 0;
    top: calc(100% + 0.625rem);
    text-align: center;
  }

  .flow figcaption {
    margin-top: 1.5rem;
  }
}

/* Cards */

.cards {
  display: grid;
  gap: 1.25rem;
  margin: 3rem 0 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 40rem) {
  .cards-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 64rem) {
  .cards-4 {
    grid-template-columns: repeat(4, 1fr);
  }

  .cards-3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

.card {
  padding: 1.5rem;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background: var(--card);
}

.card h3 {
  margin: 0;
  font-size: 1.1875rem;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

.card p {
  margin: 0.5rem 0 0;
  color: var(--muted);
  font-size: 0.96875rem;
}

.card-icon {
  display: block;
  width: 2.5rem;
  height: 2.5rem;
  margin-bottom: 1rem;
  padding: 0.5rem;
  border-radius: 10px;
  background: var(--tint);
  fill: none;
  stroke: var(--accent);
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.card > .contrast-answer {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--rule);
  color: var(--ink);
}

/* Roadmap */

.roadmap {
  margin: 3rem auto 0;
  max-width: 34rem;
  padding: 0 0 0 1.5rem;
  border-left: 2px solid var(--rule-strong);
  list-style: none;
}

.milestone {
  position: relative;
  padding-bottom: 1.75rem;
}

.milestone:last-child {
  padding-bottom: 0;
}

.milestone::before {
  content: "";
  position: absolute;
  left: calc(-1.5rem - 8px);
  top: 0.3rem;
  width: 14px;
  height: 14px;
  border: 2px solid var(--rule-strong);
  border-radius: 50%;
  background: var(--surface);
}

.milestone > p {
  margin: 0.375rem 0 0;
  color: var(--muted);
  font-size: 0.9375rem;
  line-height: 1.5;
}

.milestone > .milestone-name {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 0.625rem;
  margin: 0;
  color: var(--ink);
  font-size: 1rem;
  font-weight: 720;
}

.state {
  padding: 0.0625rem 0.5rem;
  border: 1px solid currentcolor;
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  white-space: nowrap;
}

.milestone-done::before {
  border-color: var(--done);
  background: var(--done);
}

.milestone-done .state {
  color: var(--done);
}

.milestone-active::before {
  border-color: var(--accent);
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--tint);
}

.milestone-active .state {
  color: var(--accent);
}

.milestone-launch::before {
  border-color: var(--accent);
}

.flag {
  padding: 0.0625rem 0.5rem;
  border-radius: 999px;
  background: var(--accent);
  color: var(--on-accent);
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  white-space: nowrap;
}

.milestone-later::before {
  border-style: dashed;
}

@media (min-width: 64rem) {
  .roadmap {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 1.5rem;
    max-width: none;
    padding: 1.75rem 0 0;
    border-left: 0;
    border-top: 2px solid var(--rule-strong);
  }

  .milestone {
    padding-bottom: 0;
  }

  .milestone::before {
    left: 0;
    top: calc(-1.75rem - 8px);
  }
}

/* FAQ */

.faq {
  margin-top: 2.5rem;
  border-top: 1px solid var(--rule);
}

.faq details {
  border-bottom: 1px solid var(--rule);
}

.faq summary {
  position: relative;
  padding: 1.125rem 2.5rem 1.125rem 0;
  cursor: pointer;
  font-size: 1.0625rem;
  font-weight: 650;
  list-style: none;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq summary::after {
  content: "+";
  position: absolute;
  right: 0.25rem;
  top: 50%;
  color: var(--accent);
  font-size: 1.5rem;
  font-weight: 400;
  line-height: 1;
  transform: translateY(-50%);
}

.faq details[open] > summary::after {
  content: "−";
}

/* The marker is decoration: an empty alternative keeps it out of the
   question's accessible name where browsers support one. */
@supports (content: "+" / "") {
  .faq summary::after {
    content: "+" / "";
  }

  .faq details[open] > summary::after {
    content: "−" / "";
  }
}

.faq p {
  margin: 0 0 1.375rem;
  color: var(--muted);
}

/* Footer */

.site-footer {
  border-top: 1px solid var(--rule);
  padding-block: 2.5rem 3.5rem;
  color: var(--muted);
  font-size: 0.875rem;
}

.footer-inner > p {
  margin: 0.375rem 0 0;
}

.footer-inner > .footer-brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 0.75rem;
  color: var(--ink);
  font-size: 1rem;
  font-weight: 750;
}

/* A page that does not exist */

.not-found {
  padding-block: clamp(4rem, 12vw, 8rem);
  text-align: center;
}

.not-found h1 {
  margin: 0 0 1rem;
  font-size: clamp(2.25rem, 1.4rem + 4vw, 3.5rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
}

.not-found p {
  max-width: 34rem;
  margin: 0 auto;
  color: var(--muted);
}

.not-found .actions {
  margin-top: 2rem;
}

@media print {
  .skip,
  .nav-list,
  .actions,
  .hero::before {
    display: none;
  }

  .faq details::details-content {
    content-visibility: visible;
  }

  a[href^="http"]::after {
    content: " (" attr(href) ")";
    font-size: 0.8em;
  }
}