/* --- CSS Variables for Theming --- */
:root,
[data-bs-theme="light"] {
  --body-bg: #f0f2f5;
  --card-bg: #ffffff;
  --card-border-color: rgba(0, 0, 0, 0.1);
  --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  --text-color: #212529;
  --input-bg: #f8f9fa;
  --input-border: #ced4da;
  --input-focus-bg: #ffffff;
  --input-focus-border: #86b7fe;
  --input-invalid-bg: #fff5f5;
  --placeholder-color: #6c757d;
  --link-color: #0d6efd;
  --link-hover-color: #0a58ca;
  --req-text-color: #6c757d;
  --req-valid-color: #198754;
}

[data-bs-theme="dark"] {
  --body-bg: #121212;
  --card-bg: #1e1e1e;
  --card-border-color: rgba(255, 255, 255, 0.1);
  --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  --text-color: #f8f9fa;
  --input-bg: #2a2a2a;
  --input-border: rgba(255, 255, 255, 0.15);
  --input-focus-bg: #343434;
  --input-focus-border: rgba(13, 110, 253, 0.5);
  --input-invalid-bg: #382525;
  --placeholder-color: #a0a0a0;
  --link-color: #58a6ff;
  --link-hover-color: #80b6f8;
  --req-text-color: #a0a0a0;
  --req-valid-color: #20c997;
}

body {
  background: var(--body-bg);
  background-attachment: fixed;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  overflow-x: hidden;
  transition: background 0.5s ease;
}

/* --- Theme Toggle Button --- */
.theme-toggle-container {
  position: fixed;
  top: 1rem;
  right: 1rem;
  z-index: 1050;
}
#theme-toggle {
  background-color: var(--card-bg);
  color: var(--text-color);
  border: 1px solid var(--card-border-color);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--card-shadow);
}

/* --- Modern Card --- */
.login-card {
  background: var(--card-bg);
  border-radius: 20px;
  box-shadow: var(--card-shadow);
  border: 1px solid var(--card-border-color);
  padding: 2.5rem;
  width: 100%;
  max-width: 450px;
  color: var(--text-color);
  transition: background 0.3s ease, border 0.3s ease;
}

.logo {
  max-width: 120px;
  height: auto;
}

/* --- Form Elements Styling --- */
.input-wrapper {
  position: relative;
}

.form-icon {
  position: absolute;
  top: calc((1.5em + 1rem + 2px) / 2);
  left: 1rem;
  transform: translateY(-50%);
  color: var(--placeholder-color);
  z-index: 3;
  transition: color 0.2s ease-in-out;
  pointer-events: none; /* Make icon click-through for select */
}

.input-wrapper .form-control:not([type="file"]),
.input-wrapper .form-select {
  background-color: var(--input-bg);
  border: 1px solid var(--input-border);
  border-radius: 0.5rem;
  color: var(--text-color);
  box-shadow: none;
  transition: background-color 0.2s ease-in-out, border-color 0.2s ease-in-out,
    box-shadow 0.2s ease-in-out;
  padding-left: 2.75rem;
  height: calc(1.5em + 1rem + 2px);
}

.form-select {
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23343a40' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 16px 12px;
}

[data-bs-theme="dark"] .form-select {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23f8f9fa' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e");
}

.form-select option {
  background-color: var(--card-bg);
  color: var(--text-color);
}

.form-control::placeholder {
  color: var(--placeholder-color);
  opacity: 1;
}

.input-wrapper .form-control:focus,
.input-wrapper .form-select:focus {
  border-color: var(--input-focus-border);
  box-shadow: inset 0 0 0 1px var(--input-focus-border);
  background-color: var(--input-focus-bg);
  position: relative;
  z-index: 2;
}
.input-wrapper .form-control:focus ~ .form-icon,
.input-wrapper .form-select:focus ~ .form-icon {
  color: var(--link-color);
}

.invalid-feedback {
  padding-left: 0.25rem;
}

/* --- START: Validation Icon Fixes --- */

/*
 * FIX 1: Dropdown Arrow
*/
.was-validated .form-select:valid,
.form-select.is-valid,
.was-validated .form-select:invalid,
.form-select.is-invalid {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%3cpath fill='none' stroke='%23343a40' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e") !important;
}

[data-bs-theme="dark"] .was-validated .form-select:valid,
[data-bs-theme="dark"] .form-select.is-valid,
[data-bs-theme="dark"] .was-validated .form-select:invalid,
[data-bs-theme="dark"] .form-select.is-invalid {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3e%<path fill='none' stroke='%23f8f9fa' stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='m2 5 6 6 6-6'/%3e%3c/svg%3e") !important;
}

/*
 * FIX 2: Password Field Icons
*/
.was-validated .form-control:valid ~ .toggle-password,
.form-control.is-valid ~ .toggle-password,
.was-validated .form-control:invalid ~ .toggle-password,
.form-control.is-invalid ~ .toggle-password {
  right: 2.5rem; /* Move left to make space for the validation icon */
}

/* --- END: Validation Icon Fixes --- */


/* --- Password Visibility Toggle Icon --- */
.toggle-password {
  position: absolute;
  top: calc((1.5em + 1rem + 2px) / 2);
  right: 1rem;
  transform: translateY(-50%);
  color: var(--placeholder-color);
  cursor: pointer;
  z-index: 4;
  transition: right 0.2s ease-in-out, color 0.2s ease-in-out;
}

.toggle-password:hover {
  color: var(--link-color);
}

/* --- Password Requirement Checklist --- */
.requirement-list {
  padding-left: 0.5rem;
  font-size: 0.875rem;
}
.requirement-list li {
  color: var(--req-text-color);
  transition: color 0.3s ease;
}
.requirement-list li i {
  transition: color 0.3s ease;
  width: 20px; /* Align icons */
}
.requirement-list li.valid {
  color: var(--req-valid-color);
}
.requirement-list li.valid i {
  color: var(--req-valid-color);
}

/* --- Button and Links --- */
.btn-login {
  border-radius: 50px;
  padding: 12px 20px;
  font-weight: bold;
  font-size: 1rem;
  transition: all 0.3s ease;
  border: none;
  background-image: linear-gradient(45deg, #0d6efd, #0dcaf0);
  background-size: 200% auto;
}

.btn-login:hover {
  transform: translateY(-3px);
  box-shadow: 0 4px 15px rgba(0, 123, 255, 0.3);
  background-position: right center;
}

.support-link {
  font-size: 0.9em;
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.3s ease;
}

.support-link:hover {
  color: var(--link-hover-color);
  text-decoration: underline;
}

/* --- Offline Banner --- */
#offline-banner {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  background-color: #dc3545;
  color: white;
  text-align: center;
  padding: 8px;
  z-index: 9999;
  font-size: 0.9rem;
  font-weight: 500;
  animation: slideUp 0.5s ease-out;
}

@keyframes slideUp {
  from {
    transform: translateY(100%);
  }
  to {
    transform: translateY(0);
  }
}

.input-wrapper input[type="file"].form-control {
  padding-left: 0.75rem; 
}

.input-wrapper input[type="file"].form-control::file-selector-button {
  margin-left: 1.5rem;
}


.student-id-preview {
  max-width: 150px;
  max-height: 150px;
  border-radius: 0.5rem;
  border: 1px solid var(--border-color);
  object-fit: contain; /* Use 'contain' to see the whole ID card */
}