:root {
  color-scheme: light;
  --ink: #151817;
  --muted: #616864;
  --paper: #f4f5f1;
  --surface: #ffffff;
  --line: #d6dad5;
  --teal: #087f73;
  --teal-dark: #05665d;
  --green: #dcebd8;
  --yellow: #f5d66f;
  --danger-bg: #fff4d2;
  --danger-line: #d59e17;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.5;
}

button, input, select { font: inherit; letter-spacing: 0; }
a { color: inherit; text-underline-offset: 4px; }

.site-header,
main,
footer {
  width: min(1040px, calc(100% - 40px));
  margin-inline: auto;
}

.site-header {
  min-height: 88px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  font-size: 20px;
  font-weight: 750;
  text-decoration: none;
}

.brand img {
  width: 48px;
  height: 48px;
  object-fit: contain;
  border: 1px solid var(--line);
}

.header-actions { display: flex; align-items: center; gap: 20px; }
.header-actions a { color: var(--muted); }

.version {
  padding: 4px 9px;
  border: 1px solid var(--line);
  background: var(--surface);
  font-size: 13px;
  font-weight: 700;
}

main { padding: 58px 0 76px; }

.intro { max-width: 720px; margin-bottom: 38px; }
.eyebrow, .step-label, .mode-kicker {
  margin: 0 0 8px;
  color: var(--teal-dark);
  font-size: 13px;
  font-weight: 800;
  text-transform: uppercase;
}

h1, h2, h3, p { letter-spacing: 0; }
h1 { margin: 0; font-size: clamp(42px, 7vw, 72px); line-height: 1; }
.intro > p:last-child { margin: 20px 0 0; color: var(--muted); font-size: 19px; max-width: 650px; }
h2 { margin: 0; font-size: 27px; line-height: 1.2; }
h3 { margin: 0 0 10px; font-size: 22px; }

.installer {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 28px;
  border-radius: 6px;
}

.installer-heading,
.section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
}

.compatibility {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
}
.compatibility span { width: 9px; height: 9px; background: var(--teal); border-radius: 50%; }

.mode-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 32px;
  padding: 26px 4px;
  margin-top: 26px;
  border-top: 1px solid var(--line);
}
.mode-copy p:last-child { margin: 0; color: var(--muted); max-width: 650px; }

esp-web-install-button { display: block; min-width: 205px; }
esp-web-install-button[hidden] { display: none; }
.install-button {
  width: 100%;
  min-height: 52px;
  padding: 0 22px;
  border: 1px solid var(--teal-dark);
  border-radius: 4px;
  background: var(--teal);
  color: white;
  cursor: pointer;
  font-weight: 800;
}
.install-button:hover { background: var(--teal-dark); }
.install-button:focus-visible, summary:focus-visible { outline: 3px solid var(--yellow); outline-offset: 2px; }
.browser-message { max-width: 270px; margin: 0; color: var(--muted); font-size: 14px; }

.installer-error {
  margin: 18px 0 0;
  padding: 14px 16px;
  border-left: 4px solid var(--danger-line);
  background: var(--danger-bg);
  font-size: 14px;
}

.erase-warning {
  margin-top: 20px;
  border-left: 4px solid var(--danger-line);
  background: var(--danger-bg);
  padding: 14px 16px;
  font-size: 14px;
}
.erase-warning strong { display: block; margin-bottom: 2px; }

.storage, .steps { padding-top: 58px; }
.partition-map {
  display: grid;
  grid-template-columns: 1.1fr 2.4fr .8fr 4.7fr;
  min-height: 94px;
  margin-top: 22px;
  border: 1px solid var(--ink);
  background: var(--surface);
}
.partition {
  min-width: 0;
  padding: 17px 14px;
  border-right: 1px solid var(--ink);
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.partition:last-child { border-right: 0; }
.partition span { font-weight: 800; }
.partition small { color: var(--muted); }
.partition.system { background: #e5e8e4; }
.partition.firmware { background: #d9e7e5; }
.partition.web { background: var(--yellow); }
.partition.ebooks { background: var(--green); }

.steps ol {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.steps li { display: flex; gap: 14px; padding: 22px 20px 22px 0; }
.steps li + li { border-left: 1px solid var(--line); padding-left: 20px; }
.steps li > span { font-size: 13px; font-weight: 800; color: var(--teal-dark); }
.steps p { margin: 4px 0 0; color: var(--muted); font-size: 14px; }

details { margin-top: 20px; border-bottom: 1px solid var(--line); padding-bottom: 14px; }
summary { cursor: pointer; font-weight: 750; }
details p { color: var(--muted); margin-bottom: 0; }

footer {
  min-height: 88px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--muted);
  font-size: 14px;
}

@media (max-width: 720px) {
  .site-header, main, footer { width: min(100% - 28px, 1040px); }
  .site-header { min-height: 76px; }
  .brand img { width: 40px; height: 40px; }
  .version { display: none; }
  main { padding-top: 38px; }
  h1 { font-size: 48px; }
  .installer { padding: 20px; }
  .installer-heading { align-items: flex-start; flex-direction: column; gap: 12px; }
  .mode-panel { grid-template-columns: 1fr; gap: 22px; }
  esp-web-install-button { min-width: 0; }
  .partition-map { grid-template-columns: 1fr 1fr; }
  .partition:nth-child(2) { border-right: 0; }
  .partition:nth-child(-n+2) { border-bottom: 1px solid var(--ink); }
  .steps ol { grid-template-columns: 1fr; }
  .steps li + li { border-left: 0; border-top: 1px solid var(--line); padding-left: 0; }
  footer { align-items: flex-start; flex-direction: column; justify-content: center; gap: 8px; }
}