:root {
  --bg: #fff;
  --surface: #f2f2f2;
  --text: #000;
  --muted: #7f7f7f;
  --accent: #f00;
  --accent-hover: #e60000;
  --border: #eaeaea;
  --max-w: 720px;
}

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

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

body {
  margin: 0;
  min-height: 100vh;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 16px;
  line-height: 1.5;
  color: var(--text);
  background: var(--bg);
}

a {
  color: var(--text);
  text-decoration: underline;
  text-underline-offset: 2px;
}

a:hover {
  color: #333;
}

main {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 3rem 1.5rem;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

h1 {
  margin: 0 0 1rem;
  font-size: clamp(2rem, 5vw, 2.75rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  text-align: center;
}

.hero-logo {
  display: block;
  width: 64px;
  height: 64px;
  margin: 0 auto 1.5rem;
  border-radius: 14px;
}

.lead {
  margin: 0 auto 2rem;
  font-size: 1.125rem;
  color: var(--muted);
  max-width: 36ch;
  text-align: center;
}

.features {
  display: grid;
  gap: 2rem;
  width: fit-content;
  margin: 3rem auto;
}

.feature {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}

.feature-icon {
  flex: 0 0 auto;
  width: 40px;
  height: 40px;
}

.feature-icon img {
  display: block;
  width: 40px;
  height: 40px;
}

.feature-copy h2 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 700;
}

.feature-copy p {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--muted);
}

.btn {
  display: inline-block;
  padding: 0.875rem 1.75rem;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  color: #fff;
  background: var(--accent);
  border-radius: 999px;
  border: none;
  cursor: pointer;
  transition: background 0.15s ease;
}

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

.btn:disabled,
.btn.disabled {
  background: var(--border);
  color: var(--muted);
  pointer-events: none;
}

.btn-secondary {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
}

.btn-secondary:hover {
  background: var(--border);
  color: var(--text);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 2rem;
}

.download-grid {
  display: grid;
  gap: 1rem;
  margin: 2rem 0;
}

.download-card {
  padding: 1.5rem;
  background: var(--surface);
  border-radius: 12px;
}

.download-card h2 {
  margin: 0 0 0.5rem;
  font-size: 1.125rem;
}

.download-card p {
  margin: 0 0 1rem;
  font-size: 0.9375rem;
  color: var(--muted);
}

.download-card .btn {
  font-size: 0.9375rem;
  padding: 0.65rem 1.25rem;
}

.download-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.download-note {
  color: var(--muted);
  font-size: 0.9375rem;
}

.join-box {
  margin: 2rem 0;
  padding: 2rem;
  text-align: center;
  background: var(--surface);
  border-radius: 12px;
}

.join-code {
  margin: 1rem 0;
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  font-variant-numeric: tabular-nums;
}

.join-status {
  color: var(--muted);
  font-size: 0.9375rem;
}