/* Mobile-First CSS Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* Base Mobile Styles (320px - 479px) */
body {
  font-family: Avenir, Verdana, Arial, sans-serif;
  background-color: #fafafa;
  font-size: 0.9rem;
  line-height: 1.5;
  margin: 0;
  padding: 0;
}

header {
  background-color: #bbb;
  color: white;
  padding: 0.75rem;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

/* Mobile-friendly navigation */
header a {
  color: white;
  text-decoration: none;
  padding: 0.5rem 0.25rem;
  display: inline-block;
  min-height: 44px; /* Touch-friendly tap target */
  line-height: 1.2;
  font-size: 0.85rem;
}

header a:hover {
  background-color: rgba(255,255,255,0.1);
  border-radius: 4px;
}

a {
  color: #88f;
  text-decoration: underline;
}

a:visited {
  color: #88a;
}

/* Mobile typography */
h1 {
  font-size: 1.1rem;
  font-weight: 400;
  color: white;
  margin-bottom: 0.5rem;
  line-height: 1.2;
}

h2 {
  font-size: 1.1rem;
  font-weight: 400;
  margin-bottom: 0.5rem;
  color: #444;
}

h3 {
  font-size: 1rem;
  font-weight: 400;
  margin-top: 0.25rem;
  margin-bottom: 0.1rem;
  color: #444;
}

p {
  padding-bottom: 1rem;
  line-height: 1.6;
}

ul, ol {
  margin-left: 1rem;
  padding-left: 1rem;
  margin-bottom: 1rem;
}

li {
  margin-bottom: 0.5rem;
  line-height: 1.5;
}

/* Mobile main content */
main {
  background: white;
  margin: 0.75rem;
  padding: 1.25rem;
  border-radius: 6px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.container {
  max-width: 100%;
  margin: 0;
  padding: 0;
}

.spacer {
  padding: 0 0.15rem;
  font-size: 0.8rem;
  display: inline-block;
  min-height: 44px;
  line-height: 1.2;
  vertical-align: middle;
  padding-top: 0.5rem;
  padding-bottom: 0.5rem;
}

/* Navigation improvements for mobile */
.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  align-items: center;
  margin-top: 0.5rem;
}

/* Large Mobile Styles (480px - 767px) */
@media (min-width: 480px) {
  body {
    font-size: 1rem;
  }
  
  header {
    padding: 1rem;
  }
  
  header a {
    padding: 0.5rem;
    font-size: 0.9rem;
  }
  
  h1 {
    font-size: 1.25rem;
  }
  
  h2 {
    font-size: 1.15rem;
  }
  
  h3 {
    font-size: 1.05rem;
  }
  
  main {
    margin: 1rem;
    padding: 1.5rem;
    border-radius: 8px;
  }
  
  .spacer {
    padding: 0.5rem 0.25rem;
    font-size: 0.9rem;
    display: inline-block;
    min-height: 44px;
    line-height: 1.2;
    vertical-align: middle;
  }
  
  .nav-links {
    gap: 0;
  }
}

/* Tablet Portrait (768px - 1023px) */
@media (min-width: 768px) {
  body {
    margin: 1.5rem auto;
    max-width: 90%;
    font-size: 1rem;
  }
  
  header {
    padding: 1.5rem;
  }
  
  header a {
    font-size: 1rem;
    padding: 0.5rem 0.75rem;
  }
  
  h1 {
    font-size: 1.5rem;
  }
  
  h2 {
    font-size: 1.3rem;
  }
  
  h3 {
    font-size: 1.15rem;
  }
  
  main {
    margin: 2rem auto;
    padding: 2.5rem;
    max-width: 100%;
  }
  
  .container {
    max-width: 600px;
    margin: 0 auto;
  }
  
  .spacer {
    padding: 0.5rem 0.5rem;
    font-size: 1rem;
    display: inline-block;
    min-height: 44px;
    line-height: 1.2;
    vertical-align: middle;
  }
  
  .nav-links {
    gap: 0;
    margin-top: 0.75rem;
  }
}

/* Desktop (1024px - 1439px) */
@media (min-width: 1024px) {
  body {
    max-width: 800px;
    margin: 2.5rem auto;
  }
  
  header {
    padding: 2rem 0;
  }
  
  h1 {
    font-size: 1.75rem;
    color: #444;
  }
  
  h2 {
    font-size: 1.4rem;
  }
  
  h3 {
    font-size: 1.25rem;
  }
  
  main {
    margin-top: 2rem;
    padding: 3.5rem;
    max-width: 800px;
  }
  
  .spacer {
    padding: 0.5rem 0.75rem;
    display: inline-block;
    min-height: 44px;
    line-height: 1.2;
    vertical-align: middle;
  }
  
  .nav-links {
    margin-top: 1rem;
    gap: 0;
  }
}

/* Large Desktop (1440px - 1919px) */
@media (min-width: 1440px) {
  body {
    margin: 3rem auto;
  }
  
  main {
    padding: 4rem 4rem 8rem 4rem;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.5rem;
  }
  
  h3 {
    font-size: 1.3rem;
  }
}

/* Extra Large Desktop (1920px+) */
@media (min-width: 1920px) {
  body {
    max-width: 1000px;
    margin: 4rem auto;
  }
  
  main {
    padding: 5rem 5rem 10rem 5rem;
  }
  
  .container {
    max-width: 800px;
  }
}