* {
  box-sizing: border-box;
}

html, body {
  height: 100%;
  margin: 0;
  display: flex;
  flex-direction: column;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #fdfeff;
  color: #333;
}

header {
  background: linear-gradient(90deg, #2c3e50, #34495e);
  color: #ffffff;
  padding: 40px 20px;
  text-align: center;
}

header h1 {
  font-size: 2.5rem;
  margin-bottom: 10px;
  text-shadow: 1px 1px 2px #000;
  font-weight: 600;
}

header p {
  font-size: 1.1rem;
  text-shadow: 1px 1px 1px #000;
  margin: 0;
}

nav {
  display: flex;
  justify-content: center;
  gap: 30px;
  padding: 15px 10px;
  background-color: #02000b;
  border-bottom: 1px solid #ddd;
  flex-wrap: wrap;
}

nav a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  font-size: 1rem;
  padding: 8px 0;
  position: relative;
  transition: color 0.3s;
}

nav a::after {
  content: '';
  position: absolute;
  width: 0%;
  height: 2px;
  bottom: 0;
  left: 0;
  background-color: whitesmoke;
  transition: width 0.3s ease;
}

nav a:hover {
  color: whitesmoke;
}

nav a:hover::after {
  width: 100%;
}

main {
  flex: 1;
  width: 100%;
  max-width: 900px;
  margin: 30px auto;
  padding: 0 20px;
}

@media (min-width: 1025px) {
  main {
    background: white;
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(0,0,0,0.05);
    padding: 30px;
  }
}

.account-section {
  background: white;
  padding: 25px;
  margin-bottom: 25px;
  border-radius: 8px;
  border: 1px solid #e0e0e0;
  box-shadow: 0 2px 5px rgba(0,0,0,0.05);
  animation: fadeIn 0.5s ease;
}

.account-section h2 {
  color: #2c3e50;
  font-size: 1.5rem;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 2px solid #2c3e50;
  font-weight: 600;
}

.account-section h3 {
  color: #34495e;
  font-size: 1.2rem;
  margin-bottom: 15px;
  font-weight: 600;
}

/* Profile Info */
.profile-info .info-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 0;
  border-bottom: 1px solid #f0f0f0;
}

.profile-info .info-row label {
  font-weight: 600;
  color: #555;
  flex: 0 0 150px;
}

.profile-info .info-row span {
  color: #333;
  flex: 1;
  text-align: right;
  word-break: break-word;
}

/* Session Info */
.session-info {
  background: #f8f9fa;
  padding: 15px;
  border-radius: 5px;
  margin-bottom: 15px;
}

.session-info p {
  margin: 8px 0;
}

/* Form Groups */
.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-weight: 600;
  margin-bottom: 8px;
  color: #555;
}

.form-group input {
  width: 100%;
  padding: 12px;
  border: 1px solid #ddd;
  border-radius: 5px;
  font-size: 1rem;
  transition: border-color 0.3s, box-shadow 0.3s;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.form-group input:focus {
  outline: none;
  border-color: #2c3e50;
  box-shadow: 0 0 0 3px rgba(44, 62, 80, 0.1);
}

/* Locked Field Styling */
.locked-field input:disabled,
.locked-field input:read-only {
  background-color: #f5f5f5;
  background-image: repeating-linear-gradient(
    45deg,
    transparent,
    transparent 10px,
    rgba(108, 117, 125, 0.03) 10px,
    rgba(108, 117, 125, 0.03) 20px
  );
  color: #6c757d;
  cursor: not-allowed;
  border: 1px solid #e0e0e0;
  font-style: italic;
}

.readonly-badge {
  display: inline-block;
  font-size: 0.75rem;
  padding: 2px 8px;
  background-color: #ffc107;
  color: #000;
  border-radius: 3px;
  font-weight: 600;
  margin-left: 8px;
}

.field-note {
  font-size: 0.85rem;
  color: #666;
  margin: 5px 0 0 0;
  padding: 8px 12px;
  background-color: #fff3cd;
  border-left: 3px solid #ffc107;
  border-radius: 4px;
  line-height: 1.4;
}

/* Buttons */
.btn {
  padding: 12px 25px;
  border: none;
  border-radius: 5px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s;
  margin-right: 10px;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.btn-primary {
  background-color: #2c3e50;
  color: white;
}

.btn-primary:hover {
  background-color: #34495e;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(44, 62, 80, 0.3);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-success {
  background-color: #27ae60;
  color: white;
}

.btn-success:hover {
  background-color: #229954;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(39, 174, 96, 0.3);
}

.btn-success:active {
  transform: translateY(0);
}

.btn-secondary {
  background-color: #95a5a6;
  color: white;
}

.btn-secondary:hover {
  background-color: #7f8c8d;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(149, 165, 166, 0.3);
}

.btn-secondary:active {
  transform: translateY(0);
}

.btn-warning {
  background-color: #f39c12;
  color: white;
}

.btn-warning:hover {
  background-color: #e67e22;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(243, 156, 18, 0.3);
}

.btn-warning:active {
  transform: translateY(0);
}

.btn-danger {
  background-color: #e74c3c;
  color: white;
}

.btn-danger:hover {
  background-color: #c0392b;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(231, 76, 60, 0.3);
}

.btn-danger:active {
  transform: translateY(0);
}

.button-group {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

/* Messages */
.message {
  padding: 10px;
  margin: 15px 0;
  border-radius: 5px;
  font-weight: 500;
}

/* Footer */
.footer {
  background-color: #2c3e50;
  color: white;
  text-align: center;
  padding: 15px 10px;
  font-size: 0.85em;
  margin-top: auto;
}

.footer p {
  margin: 5px 0;
}

.footer strong {
  font-weight: 600;
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Loading state */
button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none !important;
}

/* ========== TABLET RESPONSIVE (769px - 1024px) ========== */
@media (max-width: 1024px) and (min-width: 769px) {
  header {
    padding: 35px 20px;
  }

  header h1 {
    font-size: 2.2rem;
  }

  header p {
    font-size: 1.05rem;
  }

  nav {
    gap: 25px;
    padding: 14px 10px;
    flex-wrap: wrap;
  }

  nav a {
    font-size: 0.98rem;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    padding: 10px 12px;
  }

  main {
    padding: 0 30px;
    margin: 30px auto;
    max-width: 700px;
  }

  .account-section {
    padding: 25px;
    margin-bottom: 25px;
  }

  .account-section h2 {
    font-size: 1.5rem;
  }

  .account-section h3 {
    font-size: 1.25rem;
  }

  .profile-info .info-row {
    padding: 12px 0;
  }

  .profile-info .info-row label {
    flex: 0 0 150px;
    font-size: 0.95rem;
  }

  .profile-info .info-row span {
    font-size: 0.95rem;
  }

  .session-info {
    padding: 14px;
  }

  .session-info p {
    font-size: 0.95rem;
  }

  .form-group {
    margin-bottom: 18px;
  }

  .form-group label {
    font-size: 0.95rem;
  }

  .form-group input {
    padding: 12px;
    font-size: 16px;
  }

  .readonly-badge {
    font-size: 0.7rem;
  }

  .field-note {
    font-size: 0.85rem;
  }

  .btn {
    padding: 12px 22px;
    font-size: 15px;
    min-height: 44px;
  }

  .button-group {
    gap: 12px;
  }

  .footer {
    font-size: 0.82rem;
  }
}

/* ========== MOBILE RESPONSIVE (481px - 768px) ========== */
@media (max-width: 768px) {
  header {
    padding: 30px 20px;
  }

  header h1 {
    font-size: 2rem;
  }

  header p {
    font-size: 1rem;
  }

  nav {
    flex-direction: row;
    justify-content: center;
    gap: 12px;
    padding: 12px 10px;
    flex-wrap: wrap;
  }

  nav a {
    font-size: 0.9rem;
    padding: 10px 12px;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  main {
    padding: 0 20px;
    margin: 25px auto;
  }

  .account-section {
    padding: 22px 20px;
    margin-bottom: 22px;
    box-shadow: 0 1px 8px rgba(0, 0, 0, 0.06);
  }

  .account-section h2 {
    font-size: 1.45rem;
    margin-bottom: 18px;
  }

  .account-section h3 {
    font-size: 1.2rem;
    margin-bottom: 14px;
  }

  .profile-info .info-row {
    flex-direction: column;
    align-items: flex-start;
    padding: 12px 0;
    gap: 6px;
  }

  .profile-info .info-row label {
    flex: none;
    font-size: 0.93rem;
    font-weight: 600;
  }

  .profile-info .info-row span {
    text-align: left;
    font-size: 0.93rem;
    word-break: break-word;
  }

  .session-info {
    padding: 14px;
  }

  .session-info p {
    font-size: 0.93rem;
    margin: 7px 0;
  }

  .form-group {
    margin-bottom: 18px;
  }

  .form-group label {
    font-size: 0.93rem;
    margin-bottom: 8px;
  }

  .form-group input {
    padding: 13px;
    font-size: 16px; /* Prevent zoom on iOS */
    border-radius: 6px;
  }

  .readonly-badge {
    font-size: 0.7rem;
    padding: 3px 7px;
  }

  .field-note {
    font-size: 0.85rem;
    padding: 8px 12px;
    line-height: 1.5;
  }

  .button-group {
    flex-direction: column;
    gap: 10px;
  }

  .btn {
    width: 100%;
    padding: 13px 20px;
    margin-right: 0;
    margin-bottom: 0;
    font-size: 15px;
    min-height: 48px;
  }

  .message {
    padding: 11px;
    margin: 14px 0;
    font-size: 0.93rem;
  }

  .footer {
    font-size: 0.82rem;
    padding: 13px 10px;
  }
}

/* ========== SMALL MOBILE (320px - 480px) ========== */
@media (max-width: 480px) {
  header {
    padding: 25px 15px;
  }

  header h1 {
    font-size: 1.75rem;
    margin-bottom: 8px;
    line-height: 1.2;
  }

  header p {
    font-size: 0.95rem;
    line-height: 1.4;
  }

  nav {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0;
  }

  nav a {
    width: 100%;
    text-align: center;
    padding: 14px 12px;
    font-size: 0.95rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    min-height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  nav a:last-child {
    border-bottom: none;
  }

  main {
    padding: 0 15px;
    margin: 20px auto;
  }

  .account-section {
    padding: 20px 16px;
    margin-bottom: 20px;
    border-radius: 8px;
    box-shadow: 0 1px 6px rgba(0, 0, 0, 0.08);
  }

  .account-section h2 {
    font-size: 1.35rem;
    margin-bottom: 16px;
    padding-bottom: 12px;
  }

  .account-section h3 {
    font-size: 1.15rem;
    margin-bottom: 14px;
  }

  .profile-info .info-row {
    padding: 10px 0;
    gap: 6px;
  }

  .profile-info .info-row label {
    font-size: 0.9rem;
    font-weight: 600;
    color: #666;
  }

  .profile-info .info-row span {
    font-size: 0.9rem;
    color: #333;
    word-break: break-word;
    line-height: 1.5;
  }

  .session-info {
    padding: 12px;
    border-radius: 6px;
  }

  .session-info p {
    font-size: 0.88rem;
    margin: 6px 0;
    line-height: 1.5;
  }

  .form-group {
    margin-bottom: 16px;
  }

  .form-group label {
    font-size: 0.9rem;
    margin-bottom: 7px;
  }

  .form-group input {
    padding: 12px;
    font-size: 16px;
    border-radius: 6px;
  }

  .readonly-badge {
    display: block;
    margin-left: 0;
    margin-top: 6px;
    width: fit-content;
    font-size: 0.7rem;
    padding: 3px 8px;
  }

  .field-note {
    font-size: 0.82rem;
    padding: 8px 10px;
    line-height: 1.5;
    margin-top: 6px;
  }

  .btn {
    padding: 13px 18px;
    font-size: 15px;
    min-height: 48px;
    border-radius: 6px;
  }

  .button-group {
    gap: 10px;
  }

  .message {
    padding: 10px;
    margin: 12px 0;
    font-size: 0.88rem;
    line-height: 1.5;
  }

  .footer {
    font-size: 0.78rem;
    padding: 12px 10px;
    line-height: 1.5;
  }

  .footer p {
    margin: 4px 0;
  }
}

/* ========== EXTRA SMALL MOBILE (< 360px) ========== */
@media (max-width: 360px) {
  header {
    padding: 20px 12px;
  }

  header h1 {
    font-size: 1.5rem;
    margin-bottom: 6px;
  }

  header p {
    font-size: 0.88rem;
  }

  main {
    padding: 0 12px;
  }

  .account-section {
    padding: 16px 14px;
    margin-bottom: 16px;
  }

  .account-section h2 {
    font-size: 1.25rem;
    margin-bottom: 14px;
  }

  .account-section h3 {
    font-size: 1.05rem;
  }

  .profile-info .info-row {
    padding: 9px 0;
  }

  .profile-info .info-row label {
    font-size: 0.88rem;
  }

  .profile-info .info-row span {
    font-size: 0.88rem;
  }

  .session-info {
    padding: 10px;
  }

  .session-info p {
    font-size: 0.85rem;
  }

  .form-group {
    margin-bottom: 14px;
  }

  .form-group label {
    font-size: 0.88rem;
  }

  .form-group input,
  .btn {
    padding: 11px;
    font-size: 16px;
  }

  .field-note {
    font-size: 0.78rem;
    padding: 7px 8px;
  }

  .message {
    font-size: 0.85rem;
    padding: 9px;
  }

  .footer {
    font-size: 0.75rem;
    padding: 10px 8px;
  }
}

/* Accessibility improvements */
*:focus-visible {
  outline: 3px solid #2c3e50;
  outline-offset: 2px;
  border-radius: 2px;
}

/* Better focus for interactive elements */
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
a:focus-visible {
  outline: 3px solid #2c3e50;
  outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  .account-section {
    border: 2px solid #333;
  }

  .btn {
    border: 2px solid currentColor;
  }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Smooth scrolling */
html {
  scroll-behavior: smooth;
}

/* Touch-friendly tap highlights */
a, button, input {
  -webkit-tap-highlight-color: transparent;
}

/* Ensure proper touch targets on mobile (44x44px minimum) */
@media (max-width: 768px) {
  .btn,
  nav a {
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }
}

/* Prevent zoom on input focus for iOS */
@media (max-width: 768px) {
  input[type="text"],
  input[type="password"],
  input[type="email"] {
    font-size: 16px !important;
  }
}

/* Improve touch responsiveness */
@media (hover: none) and (pointer: coarse) {
  .btn:active {
    transform: scale(0.98);
    opacity: 0.9;
  }

  nav a:active {
    background-color: rgba(255, 255, 255, 0.1);
  }

  .profile-info .info-row:active {
    background-color: rgba(0, 0, 0, 0.02);
  }

  /* Larger tap targets for mobile */
  .btn,
  nav a,
  input,
  select,
  textarea {
    min-height: 48px;
  }

  /* Better touch feedback */
  button:active,
  .btn:active {
    background-color: #1a2734;
  }

  .btn-success:active {
    background-color: #1e8449;
  }

  .btn-secondary:active {
    background-color: #6c757d;
  }

  .btn-warning:active {
    background-color: #d68910;
  }

  .btn-danger:active {
    background-color: #a93226;
  }
}

/* Improved scrollbar for mobile */
@media (max-width: 768px) {
  ::-webkit-scrollbar {
    width: 8px;
  }

  ::-webkit-scrollbar-track {
    background: #f1f1f1;
  }

  ::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
  }

  ::-webkit-scrollbar-thumb:hover {
    background: #555;
  }
}
/* ========== LANDSCAPE MOBILE OPTIMIZATION ========== */
@media (max-width: 896px) and (max-height: 414px) and (orientation: landscape) {
  header {
    padding: 20px 15px;
  }

  header h1 {
    font-size: 1.5rem;
    margin-bottom: 5px;
  }

  header p {
    font-size: 0.9rem;
  }

  nav {
    padding: 10px;
    gap: 10px;
  }

  nav a {
    padding: 10px 12px;
    font-size: 0.9rem;
  }

  main {
    margin: 15px auto;
    padding: 0 20px;
  }

  .account-section {
    padding: 18px;
    margin-bottom: 18px;
  }

  .account-section h2 {
    font-size: 1.3rem;
    margin-bottom: 14px;
  }

  .form-group {
    margin-bottom: 14px;
  }

  .footer {
    padding: 10px;
  }
}

/* ========== IMPROVED PRINT STYLES ========== */
@media print {
  header,
  nav,
  .footer,
  .button-group,
  .edit-profile {
    display: none !important;
  }

  main {
    max-width: 100%;
    margin: 0;
    padding: 0;
  }

  .account-section {
    box-shadow: none;
    border: 1px solid #ddd;
    page-break-inside: avoid;
    margin-bottom: 20px;
  }

  .profile-info .info-row {
    border-bottom: 1px solid #ddd;
    padding: 10px 0;
  }

  * {
    color: #000 !important;
    background: #fff !important;
  }
}

/* ========== DARK MODE SUPPORT (Optional) ========== */
@media (prefers-color-scheme: dark) {
  /* Users can uncomment this if they want dark mode support
  html, body {
    background-color: #1a1a1a;
    color: #e0e0e0;
  }

  .account-section {
    background: #2d2d2d;
    border-color: #444;
  }

  input, select, textarea {
    background-color: #333;
    color: #e0e0e0;
    border-color: #555;
  }

  .session-info {
    background: #333;
  }
  */
}