html {
  background: #fff;
  color: #222;
  font-family: system-ui, sans-serif;
  font-size: 20px;
  line-height: 1.6;
}

body {
  max-width: 850px;
  margin: 2.5rem auto;
  padding: 0 1rem;
}

h1 {
  font-size: 2.2rem;
  margin-bottom: 1.5rem;
}

ul {
  list-style: none;
  padding: 0;
}

li {
  margin-bottom: 2rem;
  border-bottom: 1px solid #eee;
  padding-bottom: 1rem;
}

.title {
  font-weight: bold;
  font-size: 1.1em;
}

.desc {
  margin: 0.3em 0 0.5em 0;
  color: #555;
}

a {
  color: #0066cc;
  text-decoration: underline;
  word-break: break-all;
}

a:visited {
  color: #4c2882;
}


nav {
  margin-bottom: 2rem;
  padding: 1rem;
  background: #f9f9f9;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  color: #222;
  display: flex;
  gap: 1.5rem;
}

nav a {
  text-decoration: none;
  color: #222;
  padding: 0.5rem 0;
  position: relative;
  transition: color 0.2s ease;
}

nav a:hover {
  color: #0066cc;
}

nav a:visited {
  color: #222;
}

nav a.active {
  color: #0066cc;
  font-weight: bold;
}

nav a.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: #0066cc;
}

nav ul {
  margin-block-start: 0.5em;
  margin-block-end: 0.5em;
  margin-top: 0px;
  margin-bottom: 0px;

}

nav li {
  margin-bottom: 0.5rem;
  border-bottom: 1px solid #eee;
  padding-bottom: 0.5rem;
}


footer {
  margin-top: 3rem; 
  color: #888; 
  font-size: 0.9em;
}


.filters {
  margin: 0 0 2rem 0;
  padding: 1rem;
  background: #f9f9f9;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 0.5rem 1rem;
  cursor: pointer;
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 4px;
  font-size: 0.9em;
  color: #222;
  transition: all 0.2s ease;
}

.filter-btn:hover {
  background: #f0f0f0;
  border-color: #ccc;
}

.filter-btn.active {
  background: #0066cc;
  color: white;
  border-color: #0066cc;
}

#documents-list li.hidden {
  display: none;
}

/* Media queries */
@media (max-width: 600px) {
  html {
    font-size: 18px;
  }
  body {
    margin: 1rem auto;
    padding: 0 0.5rem;
  }
  .filters {
    gap: 8px;
    padding: 0.8rem;
  }
  .filter-btn {
    padding: 0.4rem 0.8rem;
    font-size: 0.8em;
  }
  nav {
    gap: 1rem;
    padding: 0.8rem;
    -webkit-overflow-scrolling: touch;
  }
  
  nav a {
    font-size: 0.9em;
  }
}