* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: #f5f5f5;
  color: #333;
}

.container {
  max-width: 750px;
  margin: 0 auto;
  background: white;
  min-height: 100vh;
}

.header {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 1rem;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.header h1 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.user-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
}

.btn {
  padding: 0.5rem 1rem;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.875rem;
  transition: all 0.3s;
}

.btn-primary {
  background: #667eea;
  color: white;
}

.btn-primary:hover {
  background: #5568d3;
}

.btn-secondary {
  background: white;
  color: #667eea;
  border: 1px solid #667eea;
}

.btn-success {
  background: #48bb78;
  color: white;
}

.nav-tabs {
  display: flex;
  background: white;
  border-bottom: 1px solid #e2e8f0;
  position: sticky;
  top: 60px;
  z-index: 99;
}

.nav-tab {
  flex: 1;
  padding: 1rem;
  text-align: center;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: all 0.3s;
}

.nav-tab.active {
  color: #667eea;
  border-bottom-color: #667eea;
}

.content {
  padding: 1rem;
}

.login-form {
  padding: 2rem;
}

.form-group {
  margin-bottom: 1rem;
}

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

.form-group input {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid #e2e8f0;
  border-radius: 4px;
  font-size: 1rem;
}

.project-card {
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 8px;
  padding: 1rem;
  margin-bottom: 1rem;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.project-card h3 {
  font-size: 1.125rem;
  margin-bottom: 0.5rem;
  color: #2d3748;
}

.project-meta {
  display: flex;
  gap: 1rem;
  margin: 0.5rem 0;
  font-size: 0.875rem;
  color: #718096;
}

.project-positions {
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid #e2e8f0;
}

.position-tag {
  display: inline-block;
  background: #edf2f7;
  color: #4a5568;
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  margin-right: 0.5rem;
  margin-bottom: 0.5rem;
  font-size: 0.875rem;
}

.loading {
  text-align: center;
  padding: 2rem;
  color: #718096;
}

.empty {
  text-align: center;
  padding: 3rem 1rem;
  color: #a0aec0;
}

.project-detail {
  padding: 1rem;
}

.detail-section {
  margin-bottom: 1.5rem;
}

.detail-section h3 {
  font-size: 1rem;
  margin-bottom: 0.75rem;
  color: #2d3748;
  font-weight: 600;
}

.position-list {
  background: #f7fafc;
  border-radius: 8px;
  padding: 1rem;
}

.position-item {
  padding: 0.75rem;
  background: white;
  border-radius: 4px;
  margin-bottom: 0.5rem;
}

.position-item h4 {
  font-size: 0.9375rem;
  margin-bottom: 0.25rem;
}

.position-item p {
  font-size: 0.875rem;
  color: #718096;
}