/* -------------------------------
   General Page Styles
--------------------------------- */
body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  line-height: 1.6;
  background-color: #f9f9f9;
  color: #333;
}

h2 {
  color: #003366;
  margin-top: 2rem;
}

p {
  margin: 0.5rem 0 1rem 0;
}

/* -------------------------------
   Section Layout
--------------------------------- */
section {
  margin: 2rem auto;
  padding: 0 1rem;
  max-width: 900px;
}

/* -------------------------------
   Banner & Header
--------------------------------- */
.site-banner {
  display: block;
  margin: 0 auto;
  width: auto;       /* natural width */
  height: auto;      /* natural height */
  max-width: 100%;   /* shrink if screen is smaller */
}

header {
  text-align: center;
  background: #f5f5f5;
  padding: 0;
}

.tagline {
  text-align: center;
  font-style: italic;
  color: #fff;
  background: #ff4500;  /* Coast Guard orange bar */
  padding: 0.5rem;
  margin: 0 0 1.5rem 0;
}

/* -------------------------------
   Grid Layout (used in visuals)
--------------------------------- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}

.grid img {
  max-width: 100%;
  border: 1px solid #ddd;
  border-radius: 6px;
  background: white;
  padding: 0.25rem;
}

/* -------------------------------
   Prototype Images
--------------------------------- */
.prototype {
  max-width: 90%;
  height: auto;
  display: block;
  margin: 1rem auto;
  border: 2px solid #ccc;
  border-radius: 8px;
  background: #f9f9f9;
  padding: 0.5rem;
}

/* -------------------------------
   Checklists (roadmap & student guide)
--------------------------------- */
.checklist {
  list-style: none;
  padding-left: 0;
  margin: 1rem 0;
}

.checklist li {
  padding-left: 1.8em;
  position: relative;
  margin-bottom: 0.5em;
  font-size: 0.95rem;
  line-height: 1.4em;
}

.checklist li::before {
  content: "☐";
  position: absolute;
  left: 0;
  color: #aaa;
  font-size: 1.2rem;
}

.checklist li.done::before {
  content: "☑";
  color: green;
}

/* -------------------------------
   Core Ideas Section
--------------------------------- */
.core-ideas {
  list-style: disc;
  padding-left: 1.5rem;
  margin: 1rem 0;
}

.core-ideas li {
  margin-bottom: 1rem;
  line-height: 1.5em;
}

/* -------------------------------
   Mobile Adjustments
--------------------------------- */
@media (max-width: 600px) {
  .site-banner {
    width: 100%;     /* make it fill small screens */
    height: auto;    /* keep proportions */
  }

  .tagline {
    font-size: 0.95em;  /* slightly smaller tagline on phones */
    padding: 0.4rem;
  }
}