:root {
  --bg-start: #eaf2ff;
  --bg-end: #f7fbff;
  --surface: #ffffff;
  --surface-soft: rgba(255, 255, 255, 0.72);
  --border: rgba(17, 63, 121, 0.12);
  --primary: #0b5fd9;
  --primary-dark: #093d8f;
  --accent: #27c46a;
  --text: #12314f;
  --muted: #5b738d;
  --shadow: 0 18px 42px rgba(14, 54, 115, 0.15);
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  min-height: 100%;
}

body {
  font-family: 'Roboto', sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, var(--bg-start), var(--bg-end));
}

.page-shell {
  width: min(100%, 720px);
  margin: 0 auto;
  padding: 18px 16px 28px;
}

.hero-card,
.panel {
  background: var(--surface-soft);
  backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.hero-card {
  padding: 18px;
  background:
    radial-gradient(circle at top right, rgba(39, 196, 106, 0.14), transparent 32%),
    linear-gradient(135deg, rgba(255, 255, 255, 0.96), rgba(238, 246, 255, 0.92));
}

.hero-topbar,
.hero-actions,
.inline-actions,
.footer-note,
.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.hero-topbar {
  margin-bottom: 16px;
}

.brand-block {
  display: flex;
  gap: 14px;
  align-items: center;
  margin-bottom: 18px;
}

.brand-logo {
  width: 68px;
  height: 68px;
  border-radius: 18px;
  box-shadow: 0 10px 24px rgba(11, 95, 217, 0.2);
}

.brand-block h1,
.hero-message h2,
.panel-head h3,
.feature-card h4 {
  margin: 0;
}

.brand-block p,
.hero-message p,
.feature-card p,
.steps,
.install-guide p,
.footer-note {
  margin: 0;
}

.brand-block h1 {
  font-size: 1.7rem;
  font-weight: 900;
}

.brand-block p,
.hero-message p,
.feature-card p,
.install-guide p {
  color: var(--muted);
  line-height: 1.5;
}

.hero-message {
  margin-bottom: 18px;
}

.hero-message h2 {
  font-size: 1.2rem;
  margin-bottom: 8px;
}

.hero-actions,
.inline-actions {
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 18px;
  border-radius: 14px;
  border: 0;
  text-decoration: none;
  font-weight: 700;
  cursor: pointer;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}

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

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  box-shadow: 0 10px 24px rgba(11, 95, 217, 0.28);
}

.btn-secondary {
  background: #edf4ff;
  color: var(--primary-dark);
}

.btn-outline {
  background: #fff;
  border: 1px solid rgba(11, 95, 217, 0.25);
  color: var(--primary-dark);
}

.btn-small {
  min-height: 42px;
  padding: 0 14px;
}

.chip {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  background: rgba(11, 95, 217, 0.1);
  color: var(--primary-dark);
  font-weight: 700;
}

.chip-action {
  border: 0;
  cursor: pointer;
}

.is-hidden {
  display: none !important;
}

.content-stack {
  display: grid;
  gap: 16px;
  margin-top: 16px;
}

.panel {
  padding: 18px;
  background: var(--surface);
}

.panel-accent {
  background: linear-gradient(135deg, #f7fffb, #eef7ff);
}

.panel-head {
  margin-bottom: 14px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(1, minmax(0, 1fr));
  gap: 12px;
}

.feature-card {
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 16px;
  background: linear-gradient(180deg, #fff, #f8fbff);
}

.feature-icon {
  display: inline-flex;
  width: 46px;
  height: 46px;
  border-radius: 14px;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
  background: linear-gradient(135deg, rgba(11, 95, 217, 0.12), rgba(39, 196, 106, 0.16));
  color: var(--primary-dark);
  font-weight: 900;
}

.steps {
  padding-left: 20px;
  color: var(--muted);
  line-height: 1.7;
}

.is-collapsed {
  display: none;
}

.footer-note {
  justify-content: center;
  gap: 10px;
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 18px;
}

@media (min-width: 640px) {
  .feature-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}