body, html {
  margin: 0;
  font-family: Arial, sans-serif;
  height: 100%;
  width: 100%;
  background: #0d0d0d;
  color: #f0f0f0;
  display: flex;
  justify-content: center;
  align-items: center;
}

body.light-theme, html.light-theme {
  background: #f5f5f5;
  color: #000;
}

.login-container {
  max-width: 350px;
  width: 100%;
  padding: 25px;
  background: rgba(0, 0, 0, 0.65);
  border-radius: 12px;
  box-shadow: 0 0 20px rgba(0,255,255,0.15);
  text-align: center;
  position: relative;
}

body.light-theme .login-container {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 0 15px rgba(0, 0, 0, 0.2);
}

.logo {
  width: 70px;
  margin-bottom: 10px;
}

h2 {
  margin: 10px 0 20px;
}

select,
input[type="text"],
input[type="password"] {
  width: 100%;
  padding: 10px;
  margin-bottom: 12px;
  border: 1px solid #333;
  background: #1c1c1c;
  color: #fff;
  border-radius: 5px;
  box-sizing: border-box;
  font-size: 14px;
}

.captcha-box {
  display: flex;
  gap: 10px;
  margin-bottom: 12px;
}

.captcha-value {
  flex: 0 0 80px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  color: #5fff5f;
  background: #1a1a1a;
  border-radius: 5px;
}

#captcha {
  flex: 1;
  padding: 10px;
  border: 1px solid #333;
  background: #1c1c1c;
  color: #fff;
  border-radius: 5px;
  box-sizing: border-box;
}

button.btn {
  background-color: #007bff;
  color: white;
  border: none;
  padding: 10px;
  border-radius: 5px;
  width: 100%;
  cursor: pointer;
  font-size: 14px;
}

button.btn:hover {
  background-color: #0056b3;
}

.register-link {
  margin-top: 10px;
  display: block;
  color: #ccc;
  font-size: 13px;
  cursor: pointer;
}

.error-message {
  color: red;
  font-size: 12px;
  margin-top: 8px;
}

#loader {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: #000;
  color: #5ff;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 20px;
  z-index: 999;
  animation: blink 1s infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.theme-switcher,
.language-switcher {
  display: inline-block;
  margin-bottom: 10px;
}

.form-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 10px;
}

input[type="checkbox"] {
  width: 30px;
  height: 16px;
  appearance: none;
  background: #444;
  border-radius: 16px;
  position: relative;
  cursor: pointer;
  margin: 0 4px;
}

input[type="checkbox"]::before {
  content: "";
  position: absolute;
  top: 2px;
  left: 2px;
  width: 12px;
  height: 12px;
  background: white;
  border-radius: 50%;
  transition: 0.2s;
}

input[type="checkbox"]:checked::before {
  transform: translateX(14px);
}

body.light-theme input,
body.light-theme select,
body.light-theme .captcha-value,
body.light-theme #captcha {
  background: #fff;
  color: #000;
  border: 1px solid #999;
}

.theme-switcher label {
  font-size: 16px;
  color: #ddd;
}

body.light-theme .theme-switcher label {
  color: #333;
}


.theme-switcher {
  display: flex;
  align-items: center;
  gap: 5px;
}

.switch {
  position: relative;
  display: inline-block;
  width: 36px;
  height: 20px;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #555;
  transition: 0.4s;
  border-radius: 34px;
}

.slider:before {
  position: absolute;
  content: "";
  height: 14px;
  width: 14px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  transition: 0.4s;
  border-radius: 50%;
}

.switch input:checked + .slider {
  background-color: #2196F3;
}

.switch input:checked + .slider:before {
  transform: translateX(16px);
}

body.light-theme .slider {
  background-color: #ccc;
}

body.light-theme .switch input:checked + .slider {
  background-color: #2196F3;
}