/* base.css */
/* 1. Reset & Base Typography */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.6;
  color: #1a1a1a;
  background-color: #f9fafb;
}
h1, h2, h3, h4, h5, h6 {
  color: #1a1a1a;
  margin-bottom: 1rem;
  font-weight: 600;
}
h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.75rem; }
p {
  font-size: 1.1rem;
  margin-bottom: 1rem;
  color: #4b5563;
}
a {
  color: #3b82f6;
  text-decoration: none;
  transition: color 0.3s ease;
}
a:hover {
  color: #2563eb;
}
ul { list-style: none; }
hr {
  border: 0;
  border-top: 1px solid #e5e7eb;
  margin: 1.5rem 0;
}

/* 2. Header & Navigation */
.site-header {
  background-color: #ffffff;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0;
}
.site-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #1a1a1a;
  text-decoration: none;
}
.site-subtitle {
  font-size: 0.9rem;
  color: #4b5563;
}
.top-nav {
  display: flex;
  gap: 1.5rem;
}
.top-nav a {
  font-size: 1rem;
  color: #1a1a1a;
}
.top-nav a.active,
.top-nav a:hover {
  color: #3b82f6;
}
.mobile-nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
}
.top-nav.show {
  display: flex;
  flex-direction: column;
}

/* 3. Footer */
.site-footer {
  text-align: center;
  padding: 2rem 0;
  background-color: #f9fafb;
}
.site-footer hr {
  margin-bottom: 1.5rem;
}
.site-footer p {
  color: #4b5563;
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}
.site-footer a {
  color: #3b82f6;
}
.site-footer a:hover {
  color: #2563eb;
}

/* 4. Utilities */
.button {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background-color: #3b82f6;
  color: white;
  border-radius: 6px;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.3s ease;
}
.button:hover {
  background-color: #2563eb;
}
.reset-button {
  background: none;
  border: none;
  color: #3b82f6;
  text-decoration: underline;
  cursor: pointer;
  font-size: 1rem;
}
.reset-button:hover {
  color: #2563eb;
}