body {
  margin: 0;
  font-family: Arial;
  background: linear-gradient(135deg, #0b0b0b, #1a1a1a);
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

/* box */
.login-box {
  background: #111;
  padding: 30px;
  border-radius: 12px;
  width: 320px;
  box-shadow: 0 0 25px rgba(0,0,0,0.7);
  text-align: center;
}

.login-box h2 {
  color: #fff;
  margin-bottom: 20px;
}

/* error */
.error {
  background: #330000;
  color: #ff4d4d;
  padding: 8px;
  border-radius: 6px;
  margin-bottom: 15px;
  font-size: 13px;
}

/* input */
.login-box input {
  width: 100%;
  padding: 10px;
  margin-bottom: 12px;
  border: none;
  border-radius: 6px;
  background: #1f1f1f;
  color: #fff;
}

/* focus */
.login-box input:focus {
  outline: none;
  box-shadow: 0 0 6px red;
}

/* button */
.login-box button {
  width: 100%;
  padding: 10px;
  background: red;
  border: none;
  border-radius: 6px;
  color: white;
  font-weight: bold;
  cursor: pointer;
  transition: 0.3s;
}

.login-box button:hover {
  background: #ff2a2a;
}