html, body {
  height: 100%;
  min-height: 100vh;
  background-color: #0a2233;
}
html, body {
  height: 100%;
  min-height: 100vh;
}
body.dark-mode {
  background-color: #0a2233;
  color: #f8f9fa;
  background-image: url("../images/01.avif");
  background-size: cover;
  background-repeat: no-repeat;
  background-position: center bottom;
  background-attachment: fixed;
}
body.light-mode {
  background-color: #f8f9fa;
  color: #212529;
  background-image: url("../images/01.avif");
  background-size: cover;
  background-repeat: no-repeat;
  background-position: center bottom;
  background-attachment: fixed;
}
.custom-card {
  max-width: 50rem;
  margin: 0 auto;
  border-radius: 10px !important;
  background: transparent;
}
body.light-mode .custom-card {
  background: rgba(255,255,255,0.92);
  color: #212529;
}
body.dark-mode .custom-card {
  background: rgba(10,34,51,0.96);
  color: #f8f9fa;
}

/* Toggle Theme button contrast */
#themeToggle {
  background: #212529;
  color: #fff;
  border: none;
  transition: background 0.2s, color 0.2s;
}
body.light-mode #themeToggle {
  background: #f8f9fa;
  color: #212529;
  border: 1px solid #212529;
}
body.dark-mode #themeToggle {
  background: #212529;
  color: #fff;
  border: 1px solid #fff;
}
#themeToggle:hover, #themeToggle:focus {
  filter: brightness(1.1);
  outline: 2px solid #888;
}

/* Link color for dark mode */
body.dark-mode a, body.dark-mode a:visited {
  color: #4dc3ff;
}
body.light-mode a, body.light-mode a:visited {
  color: #0a2233;
}

/* Register button color for both themes */
body.dark-mode #submit {
  background: #4dc3ff;
  color: #0a2233;
  border: none;
}
body.light-mode #submit {
  background: #0a2233;
  color: #fff;
  border: none;
}
#submit:disabled {
  opacity: 0.6;
}

/* Alert box background for dark mode */
body.dark-mode .alert-info {
  background: rgba(77,195,255,0.15);
  color: #b8e6ff;
  border-color: #4dc3ff;
}
body.light-mode .alert-info {
  background: #e9f7fe;
  color: #0a2233;
  border-color: #b8e6ff;
}

/* Input backgrounds for dark mode */
body.dark-mode .form-control {
  background: #18344a;
  color: #fff;
  border: 1px solid #4dc3ff;
}
body.dark-mode .form-control:focus {
  background: #204060;
  color: #fff;
  border-color: #4dc3ff;
}
body.light-mode .form-control {
  background: #fff;
  color: #212529;
  border: 1px solid #0a2233;
}
body.light-mode .form-control:focus {
  background: #f0f8ff;
  color: #212529;
  border-color: #0a2233;
}

/* Remove white from mb-0 ul in alert */
body.dark-mode .alert-info ul.mb-0 {
  background: transparent;
  color: #b8e6ff;
}