* {
  box-sizing: border-box;
  font-family: "Segoe UI", sans-serif;
}

body {
  background-color: #f8f9fa;
  color: #212529;
  margin: 0;
  padding: 0;

  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.container {
  width: 500px;
  margin: auto;
  padding: 20px;
  background-color: #ffffff;
  border-radius: 12px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.05);
  text-align: center;

  transform: scale(1.1);
}

/* result input */
.password-container {
  position: relative;
  margin-top: 25px;
}

.password-container input[type="text"],
.password-container input[type="text"]:focus {
  width: 100%;
  padding: 14px 90px 14px 16px;
  font-size: 17px;
  font-weight: 500;
  text-align: left;
  border: 2px solid #007acc;
  border-radius: 8px;
  background-color: #f0f8ff;
  color: #1b1b1b;
  box-shadow: inset 0 0 5px rgba(0, 0, 0, 0.05);
  outline: none;
}

.password-container input[type="text"]::placeholder {
  color: #888;
  font-style: italic;
}

.function-button-container {
  display: inline;
}

.password-container button {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background-color: #007acc;
  border: none;
  padding: 8px 12px;
  color: #fff;
  font-size: 16px;
  border-radius: 6px;
  cursor: pointer;
  transition: background-color 0.2s;
}

.password-container button:hover {
  background-color: #005f99;
}

#copyButton {
  right: 50px;
}

#generateButton {
  right: 6px;
}

.mobile-text {
  display: none;
  font-size: 16px;
  font-weight: 700;
  margin-left: 5px;
}

#copyStatus {
  font-size: 16px;
  text-align: center;
  color: #28a745;
  height: 1em;
  margin-bottom: 20px;
}

/* form */
form {
  text-align: left;
  margin-bottom: 20px;
}

form label {
  display: block;
  margin: 15px 0 5px;
  font-weight: 500;
  cursor: pointer;
  user-select: none;
}

/* checkbox */
input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  background-color: #fff;
  border: 2px solid #007acc;
  padding: 6px;
  border-radius: 4px;
  display: inline-block;
  position: relative;
  vertical-align: middle;
  cursor: pointer;
  margin-right: 10px;
}

input[type="checkbox"]:checked::after {
  content: "✓";
  position: absolute;
  top: -6px;
  left: 1px;
  color: #007acc;
  font-size: 16px;
  font-weight: bold;
}

/* range */
input[type="range"] {
  appearance: none;
  width: 100%;
  height: 8px;
  background: linear-gradient(90deg, #007acc, #00c4cc);
  border-radius: 5px;
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  background: #007acc;
  border-radius: 50%;
  border: 2px solid #fff;
  cursor: pointer;
  box-shadow: 0 0 2px rgba(0, 0, 0, 0.5);
}

input[type="range"]::-moz-range-thumb {
  width: 20px;
  height: 20px;
  background: #007acc;
  border-radius: 50%;
  border: 2px solid #fff;
  cursor: pointer;
}

/* length span */
#passwdLength {
  font-weight: bold;
  color: #007acc;
  margin-left: 5px;
}

/* responsiveness */
@media (max-width: 600px) {
  .container {
    width: 95%;
    margin: auto;
    padding: 15px 25px;
    transform: scale(1);
  }

  .password-container input[type="text"] {
    padding-right: 16px;
  }

  .function-button-container {
    display: flex;
    justify-content: space-evenly;
    align-items: center;
    margin: 10px auto 0;
  }

  #copyButton,
  #generateButton {
    position: static;
    transform: translateY(0);
  }

  .mobile-text {
    display: inline;
  }

  #copyStatus {
    font-size: 20px;
    margin: 10px auto 0;
    height: 1.5em;
  }
}