body { font-family: Arial, Helvetica, sans-serif; max-width:900px; margin:20px auto; padding:0 15px; }
header, footer { margin:20px 0; }
.article-intro { color:#333; }
nav a{ margin-right:10px; }
.form-field{ margin-bottom:10px; }
input[type=text], textarea { width:100%; padding:8px; box-sizing:border-box; }
button { padding:8px 12px; }
.table { width:100%; border-collapse:collapse; }
.table td, .table th { border:1px solid #ddd; padding:8px; }
@media (max-width:600px){ body{padding:10px;} }
.message { padding:8px; margin:10px 0; border-radius:4px; }
.message.success { background:#e6ffea; border:1px solid #b7f2c6; }
.message.error { background:#ffecec; border:1px solid #f2b8b8; }