html { scroll-behavior: smooth; }

body{
  background: linear-gradient(180deg, #cfd9df 0%, #8d99a6 100%);
  background-attachment: fixed;
  margin: 0;
}

*{
  color: #f5f5f7;
  font-size: 15px;
  font-family: 'Comic Neue';
}

div {
  background: rgba(40, 40, 40, 0.55);
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0,0,0,0.35);
  margin: 24px auto;
  padding: 22px 20px;
  text-align: center;
  backdrop-filter: blur(20px);
  max-width: 980px;
}

h2{
  text-align: center;
  color: #ffffff;
  text-shadow: 0 1px 2px rgba(0,0,0,0.6);
  letter-spacing: .3px;
  margin-top: 4px;
}

.intro h1{
  text-align: center;
  margin: 6px 0 10px;
}

.micro-intro{
  opacity: .9;
}

ul{
  list-style: disc inside;
  line-height: 1.55;
  text-align: left;
  margin: 8px auto 0;
  max-width: 740px;
}

.callout{
  margin: 14px auto 0;
  padding: 12px 14px;
  border-radius: 12px;
  max-width: 740px;
  text-align: left;
}
.callout.tip{
  background: rgba(80, 160, 255, 0.15);
  border: 1px solid rgba(80,160,255,0.35);
}
.callout.warn{
  background: rgba(255, 160, 90, 0.15);
  border: 1px solid rgba(255,160,90,0.35);
}

.parts{
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 14px;
  margin-top: 14px;
}
.parts img{
  width: 100%;
  height: 110px;
  object-fit: cover;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,.25);
}

.nav{
  position: sticky;
  top: 0;
  z-index: 10;
  max-width: 980px;
  margin: 12px auto;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.2);
  backdrop-filter: blur(20px);
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 18px;
  padding: 12px 16px;
  box-shadow: 0 6px 18px rgba(0,0,0,0.25);
  border-radius: 14px;
}

.nav img{
  width: 20px;
  height: 20px;
  border-radius: 4px;
  box-shadow: none;
  margin-right: 6px;
}

.nav a:hover,
.nav a:focus{
  text-decoration: underline;
  outline: none;
}