:root {
  --sdh-bg: #f6f8fb;
  --sdh-surface: #ffffff;
  --sdh-text: #172033;
  --sdh-muted: #657086;
  --sdh-line: #e6eaf0;
  --sdh-accent: #213d79;
  --sdh-danger: #c73535;
  --sdh-header-h: 58px;
  --sdh-footer-h: 64px;
  --sdh-max-mobile: 430px;
  --sdh-radius: 14px;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  overflow-x: hidden;
  color: var(--sdh-text);
  background: var(--sdh-bg);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.5;
}
button, input, textarea, select { font: inherit; }
a { color: var(--sdh-accent); text-decoration: none; }
img { max-width: 100%; display: block; }

.sdh-app {
  width: 100%;
  min-height: 100dvh;
  margin: 0 auto;
  background: var(--sdh-surface);
}

.sdh-main {
  min-height: 100dvh;
  padding-top: var(--sdh-header-h);
  padding-bottom: calc(var(--sdh-footer-h) + env(safe-area-inset-bottom));
}


@media (min-width: 431px) {
  body { background: #edf0f5; }
  .sdh-app { max-width: var(--sdh-max-mobile); box-shadow: 0 0 28px rgba(22, 32, 51, .08); }
}