/* シンプルで見た目の良いログインフォーム */
body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue",
    Arial;
  background: linear-gradient(180deg, #f5f7fb, #eef2f7);
  height: 100vh;
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}
.login-container {
  background: #fff;
  padding: 32px;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  width: 360px;
}
.login-container h1 {
  margin: 0 0 16px;
  font-size: 20px;
}
.login-form label {
  display: block;
  margin-bottom: 12px;
  font-size: 14px;
  color: #333;
}
.login-form input[type="text"],
.login-form input[type="password"] {
  width: 100%;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 6px;
  box-sizing: border-box;
}
.login-form button {
  display: block;
  width: 100%;
  padding: 10px;
  border: none;
  background: #0073e6;
  color: #fff;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
}
.flash {
  background: #fff3cd;
  border-left: 4px solid #ffecb5;
  padding: 10px;
  margin-bottom: 12px;
  border-radius: 6px;
  color: #7a5a00;
}