:root {
  color-scheme: dark;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #0c0f11;
  color: #f2f5f6;
  font-synthesis: none;
  --surface: #151a1e;
  --surface-strong: #1d2429;
  --line: #323c43;
  --muted: #9caab2;
  --green: #53d993;
  --blue: #4b9fe3;
  --amber: #f2bd5a;
  --danger: #f0786d;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  background: #0c0f11;
  line-height: 1.5;
  letter-spacing: 0;
}

a { color: #9ed2fa; }
a:hover { color: #d2ebff; }

.site-header {
  min-height: 76px;
  padding: 12px clamp(20px, 4vw, 64px);
  border-bottom: 1px solid var(--line);
  background: #111518;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand img {
  border: 1px solid #3b454b;
  border-radius: 6px;
}

.brand strong,
.brand span { display: block; }
.brand strong { font-size: 1rem; }
.brand span { color: var(--muted); font-size: 0.8rem; }

nav { display: flex; gap: 20px; }
nav a { color: #d9e1e5; text-decoration: none; font-size: 0.9rem; }

main {
  width: min(1040px, calc(100% - 40px));
  margin: 0 auto;
  padding: 48px 0 64px;
}

.intro {
  max-width: 720px;
  margin-bottom: 32px;
}

.eyebrow,
.step {
  margin: 0 0 6px;
  color: var(--green);
  font-size: 0.73rem;
  font-weight: 800;
}

h1,
h2,
p { margin-top: 0; }
h1 { margin-bottom: 12px; font-size: clamp(2rem, 5vw, 3.3rem); line-height: 1.06; }
h2 { margin-bottom: 0; font-size: 1.15rem; }
.intro > p:last-child { color: #bec8cd; font-size: 1.04rem; }

.flasher,
.checks {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.flasher { padding: clamp(20px, 4vw, 36px); }
.checks { margin-top: 20px; padding: 28px 32px; }

.section-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 24px;
}

.status {
  padding-left: 14px;
  border-left: 3px solid var(--amber);
  color: var(--muted);
  font-size: 0.82rem;
}

.status.ready { border-color: var(--green); color: #c6f5dc; }
.status.error { border-color: var(--danger); color: #ffc0ba; }

.field span {
  display: block;
  margin-bottom: 8px;
  color: #dce3e7;
  font-weight: 700;
  font-size: 0.88rem;
}

select {
  width: 100%;
  min-height: 48px;
  padding: 0 42px 0 14px;
  border: 1px solid #46535b;
  border-radius: 6px;
  background: #0e1215;
  color: #fff;
  font: inherit;
}

select:focus-visible,
button:focus-visible,
a:focus-visible { outline: 3px solid rgba(75, 159, 227, 0.55); outline-offset: 2px; }

.device-data {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin: 24px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.device-data div {
  min-width: 0;
  padding: 17px 16px;
  border-right: 1px solid var(--line);
}
.device-data div:first-child { padding-left: 0; }
.device-data div:last-child { border-right: 0; }
.device-data dt { color: var(--muted); font-size: 0.74rem; }
.device-data dd { margin: 4px 0 0; font-weight: 750; overflow-wrap: anywhere; }

.warning {
  display: grid;
  grid-template-columns: minmax(190px, 0.7fr) 2fr;
  gap: 20px;
  padding: 16px 18px;
  border-left: 4px solid var(--amber);
  background: #241f16;
  color: #e4d5b6;
}
.warning strong { color: #ffdb92; }
code { color: #d9f1ff; overflow-wrap: anywhere; }

.install-area {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 30px 0 24px;
}
.install-area p:last-child { margin: 7px 0 0; color: var(--muted); font-size: 0.88rem; }

esp-web-install-button {
  --esp-tools-button-color: #2f89ca;
  --esp-tools-button-text-color: #ffffff;
  --esp-tools-button-border-radius: 6px;
  flex: 0 0 auto;
}

.install-button {
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid #60b1e9;
  border-radius: 6px;
  background: #2f89ca;
  color: #fff;
  font: inherit;
  font-weight: 800;
  cursor: pointer;
}
.install-button:hover { background: #3b98d8; }
.install-button span { margin-right: 8px; }
.browser-message { max-width: 380px; color: #ffc0ba; }

.downloads {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px 20px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  font-size: 0.84rem;
}
.downloads span { color: var(--muted); font-weight: 750; }

.checks ol {
  margin: 0;
  padding-left: 24px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px 42px;
  color: #c5cfd4;
}
.checksum {
  margin: 24px 0 0;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.78rem;
}

footer {
  min-height: 72px;
  padding: 20px clamp(20px, 4vw, 64px);
  border-top: 1px solid var(--line);
  background: #111518;
  display: flex;
  align-items: center;
  gap: 24px;
  color: var(--muted);
  font-size: 0.8rem;
}
footer span { margin-right: auto; }

@media (max-width: 720px) {
  .site-header { align-items: flex-start; }
  nav { display: none; }
  main { width: min(100% - 24px, 1040px); padding-top: 32px; }
  .device-data { grid-template-columns: 1fr 1fr; }
  .device-data div:nth-child(2) { border-right: 0; }
  .device-data div:nth-child(-n + 2) { border-bottom: 1px solid var(--line); }
  .device-data div:nth-child(3) { padding-left: 0; }
  .warning { grid-template-columns: 1fr; gap: 6px; }
  .install-area { align-items: stretch; flex-direction: column; }
  .install-button { width: 100%; }
  .checks { padding: 24px 20px; }
  .checks ol { grid-template-columns: 1fr; }
  footer { align-items: flex-start; flex-direction: column; gap: 8px; }
  footer span { margin-right: 0; }
}