/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #fff;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  margin-bottom: 1rem;
  font-weight: 600;
  line-height: 1.2;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.1rem; }
h6 { font-size: 1rem; }

p {
  margin-bottom: 1rem;
}

a {
  color: #007bff;
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: #0056b3;
  text-decoration: underline;
}

/* Layout */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.row {
  display: flex;
  flex-wrap: wrap;
  margin: 0 -15px;
}

.col {
  flex: 1;
  padding: 0 15px;
}

/* Header */
header {
  background-color: #f8f9fa;
  padding: 1rem 0;
  border-bottom: 1px solid #dee2e6;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 2rem;
}

nav a {
  font-weight: 500;
  padding: 0.5rem 0;
}

/* Main Content */
main {
  padding: 2rem 0;
  min-height: calc(100vh - 200px);
}

section {
  margin-bottom: 3rem;
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background-color: #007bff;
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 1rem;
  transition: background-color 0.3s ease;
}

.btn:hover {
  background-color: #0056b3;
  text-decoration: none;
  color: white;
}

.btn-secondary {
  background-color: #6c757d;
}

.btn-secondary:hover {
  background-color: #5a6268;
}

/* Cards */
.card {
  background: white;
  border: 1px solid #dee2e6;
  border-radius: 8px;
  padding: 1.5rem;
  margin-bottom: 1rem;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

/* Forms */
input, textarea, select {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid #ced4da;
  border-radius: 4px;
  margin-bottom: 1rem;
  font-size: 1rem;
}

input:focus, textarea:focus, select:focus {
  outline: none;
  border-color: #007bff;
  box-shadow: 0 0 0 2px rgba(0,123,255,0.25);
}

label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
}

/* Footer */
footer {
  background-color: #343a40;
  color: white;
  text-align: center;
  padding: 2rem 0;
  margin-top: auto;
}

footer a {
  color: #adb5bd;
}

footer a:hover {
  color: white;
}

/* Utilities */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mt-5 { margin-top: 3rem; }

.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.mb-5 { margin-bottom: 3rem; }

.p-1 { padding: 0.25rem; }
.p-2 { padding: 0.5rem; }
.p-3 { padding: 1rem; }
.p-4 { padding: 1.5rem; }
.p-5 { padding: 3rem; }

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    padding: 0 15px;
  }
  
  .row {
    flex-direction: column;
  }
  
  nav ul {
    flex-direction: column;
    gap: 1rem;
  }
  
  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  h3 { font-size: 1.25rem; }
  
  main {
    padding: 1rem 0;
  }
}