* { box-sizing: border-box; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: #f4f5f7;
  margin: 0;
  color: #1a1a1a;
}
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #1a2b4a;
  color: white;
  padding: 16px 32px;
}
header h1 { font-size: 18px; margin: 0; }
main {
  max-width: 800px;
  margin: 32px auto;
  padding: 0 16px;
}
.form-block, .history-block {
  background: white;
  border-radius: 10px;
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.08);
}
label { display: block; margin: 12px 0 4px; font-weight: 600; font-size: 14px; }
input[type=text], input[type=password], input[type=number] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid #d0d5dd;
  border-radius: 6px;
  font-size: 15px;
}
button {
  margin-top: 16px;
  background: #2f6feb;
  color: white;
  border: none;
  padding: 10px 20px;
  border-radius: 6px;
  font-size: 15px;
  cursor: pointer;
}
button:hover { background: #2557c7; }
.link-btn {
  background: none;
  border: none;
  color: #cdd6e6;
  text-decoration: underline;
  cursor: pointer;
  margin: 0;
  padding: 0;
  font-size: 14px;
}
.error {
  background: #fde8e8;
  color: #c0392b;
  padding: 10px 14px;
  border-radius: 6px;
  margin-bottom: 12px;
}
.success {
  background: #e8f9ee;
  color: #1e7a3d;
  padding: 10px 14px;
  border-radius: 6px;
  margin-bottom: 12px;
}
table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 8px 10px; border-bottom: 1px solid #eee; font-size: 14px; }
.status-paid { color: #1e7a3d; font-weight: 600; }
.status-created { color: #b8860b; }
.login-box {
  max-width: 360px;
  margin: 80px auto;
  background: white;
  padding: 32px;
  border-radius: 10px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.08);
}