:root {
  --page-bg: #f2f2f2;
  --panel-bg: #ffffff;
  --text: #51545c;
  --muted: #8a8d94;
  --border: #d7d7d7;
  --nav-top: #5ba4df;
  --nav-bottom: #2f72a7;
  --nav-active: #2f6fa2;
  --link: #6fa2c0;
  --page-gutter: clamp(22px, 6.5vw, 70px);
}

* {
  box-sizing: border-box;
}

html {
  font-family: "Roboto", Arial, Helvetica, sans-serif;
  font-size: 16px;
  color: var(--text);
  background:
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.55) 0, rgba(255, 255, 255, 0.55) 1px, transparent 1px, transparent 4px),
    var(--page-bg);
}

body {
  margin: 0;
  line-height: 1.45;
}

a {
  color: var(--link);
}

a:hover,
a:focus {
  color: #1d4f82;
}

.site {
  max-width: 1170px;
  margin: 0 auto;
  background: var(--panel-bg);
  box-shadow: 0 0 8px rgba(0, 0, 0, 0.08);
}

.site-header {
  padding: 32px 0 40px;
  border-top: 3px solid rgba(0, 0, 0, 0.18);
  background:
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.65) 0, rgba(255, 255, 255, 0.65) 1px, transparent 1px, transparent 4px),
    #f5f5f5;
}

.brand {
  padding: 0 var(--page-gutter);
}

.site-title {
  display: inline-block;
  color: #51545c;
  font-size: 3.05rem;
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.03em;
  text-decoration: none;
}

.tagline {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 1rem;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  padding-left: var(--page-gutter);
  background: linear-gradient(to bottom, var(--nav-top), var(--nav-bottom));
  border-top: 1px solid #72b5ec;
  border-bottom: 1px solid #1d4f76;
  box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.34), inset 0 -1px 0 rgba(0, 0, 0, 0.25);
}

.site-nav a {
  display: block;
  padding: 19px 12px 20px;
  color: #ffffff;
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1;
  text-decoration: none;
  text-shadow: 0 1px 0 rgba(0, 0, 0, 0.32);
  border-left: 1px solid rgba(255, 255, 255, 0.14);
  border-right: 1px solid rgba(0, 0, 0, 0.18);
}

.site-nav a:hover,
.site-nav a:focus,
.site-nav a.active {
  background: linear-gradient(to bottom, #428ccb, var(--nav-active));
  box-shadow: inset 0 0 12px rgba(0, 0, 0, 0.18);
}

.hero img {
  display: block;
  width: 100%;
  height: auto;
}

.content {
  padding: 58px var(--page-gutter) 46px;
}

.content h1 {
  margin: 0 0 48px;
  color: #51545c;
  font-size: 2.9rem;
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.045em;
}

.content p {
  margin: 0 0 1.05rem;
  font-size: 1.24rem;
  line-height: 1.38;
}

.contact {
  margin-top: 22px;
}

.contact p {
  margin-bottom: 0.35rem;
}

.catalog-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 22px;
}

.catalog-heading h1 {
  margin-bottom: 0;
}

.button {
  display: inline-block;
  padding: 10px 16px;
  color: #ffffff;
  background: linear-gradient(to bottom, var(--nav-top), var(--nav-bottom));
  border-radius: 3px;
  font: 700 0.95rem/1 "Roboto", Arial, Helvetica, sans-serif;
  text-decoration: none;
  text-shadow: 0 1px 0 rgba(0, 0, 0, 0.32);
}

.button:hover,
.button:focus {
  color: #ffffff;
  background: var(--nav-active);
}

.pdf-viewer {
  display: block;
  width: 100%;
  height: min(82vh, 940px);
  min-height: 640px;
  border: 1px solid var(--border);
  background: #f4f4f4;
}

@media (max-width: 720px) {
  .site {
    margin: 0;
  }

  .site-title {
    font-size: 2.5rem;
  }

  .content {
    padding-left: var(--page-gutter);
    padding-right: var(--page-gutter);
  }

  .catalog-heading {
    align-items: flex-start;
    flex-direction: column;
  }

  .pdf-viewer {
    min-height: 520px;
  }
}