* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: #f5f5f7;
  min-height: 100vh;
}

.screen {
  display: none;
}

.screen.active {
  display: block;
}

/* Login Screen */
.login-container {
  max-width: 400px;
  margin: 0 auto;
  padding: 3rem 2rem;
  text-align: center;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.login-logo {
  font-size: 4rem;
  margin-bottom: 1rem;
}

.login-container h1 {
  font-size: 1.5rem;
  font-weight: 600;
  color: #1d1d1f;
  margin-bottom: 0.5rem;
}

.login-container p {
  color: #6e6e73;
  margin-bottom: 2rem;
  font-size: 0.95rem;
}

#loginForm {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

#loginForm input {
  padding: 1rem;
  font-size: 1.1rem;
  border: 2px solid #e5e5ea;
  border-radius: 12px;
  text-align: center;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

#loginForm input:focus {
  outline: none;
  border-color: #007aff;
}

#loginForm button {
  padding: 1rem;
  font-size: 1rem;
  font-weight: 600;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
}

#loginForm button:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

#loginForm button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.error-message {
  color: #ff3b30;
  margin-top: 1rem;
  font-size: 0.9rem;
}

.portal-footer {
  margin-top: 3rem;
  color: #8e8e93;
  font-size: 0.85rem;
}

/* Browser Screen */
header {
  background: white;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid #e5e5ea;
  position: sticky;
  top: 0;
  z-index: 100;
}

header h1 {
  font-size: 1.25rem;
  font-weight: 600;
  color: #1d1d1f;
}

.btn {
  padding: 0.5rem 1rem;
  font-size: 0.85rem;
  font-weight: 500;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s;
}

.btn-secondary {
  background: #e5e5ea;
  color: #1d1d1f;
}

.btn-secondary:hover {
  background: #d1d1d6;
}

main {
  max-width: 900px;
  margin: 0 auto;
  padding: 1.5rem;
}

/* Breadcrumb */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}

.breadcrumb-item {
  color: #007aff;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
}

.breadcrumb-item:hover {
  background: #e5e5ea;
}

.breadcrumb-item:last-child {
  color: #1d1d1f;
  font-weight: 500;
}

.breadcrumb-separator {
  color: #8e8e93;
  padding: 0.25rem 0;
}

/* File List */
.file-list {
  background: white;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.file-item {
  display: flex;
  align-items: center;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid #f0f0f0;
  transition: background 0.15s;
}

.file-item:last-child {
  border-bottom: none;
}

.file-item:hover {
  background: #f9f9fb;
}

.file-icon {
  font-size: 1.5rem;
  margin-right: 1rem;
  width: 2rem;
  text-align: center;
}

.file-info {
  flex: 1;
  min-width: 0;
}

.file-name {
  font-weight: 500;
  color: #1d1d1f;
  word-break: break-word;
}

.file-name.folder {
  color: #007aff;
  cursor: pointer;
}

.file-meta {
  font-size: 0.8rem;
  color: #8e8e93;
  margin-top: 0.25rem;
}

.file-actions {
  display: flex;
  gap: 0.5rem;
}

.btn-download {
  background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
  color: white;
  padding: 0.5rem 1rem;
  font-size: 0.8rem;
}

.btn-download:hover {
  box-shadow: 0 2px 8px rgba(17, 153, 142, 0.4);
}

.loading {
  padding: 3rem;
  text-align: center;
  color: #8e8e93;
}

.empty-state {
  padding: 3rem;
  text-align: center;
  color: #8e8e93;
}

footer {
  text-align: center;
  padding: 2rem;
  color: #8e8e93;
  font-size: 0.85rem;
}

/* Responsive */
@media (max-width: 600px) {
  main {
    padding: 1rem;
  }
  
  .file-item {
    flex-wrap: wrap;
    gap: 0.75rem;
  }
  
  .file-actions {
    width: 100%;
    justify-content: flex-end;
  }
}

/* Backup warning */
.backup-warning {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  background: linear-gradient(135deg, #fff3cd 0%, #ffeaa7 100%);
  border-bottom: 1px solid #f0d78c;
  color: #856404;
  font-size: 0.9rem;
}

.warning-icon {
  font-size: 1.25rem;
}

/* Disabled button */
.btn-disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* Download overlay */
.download-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.download-message {
  background: white;
  padding: 2rem 3rem;
  border-radius: 12px;
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 1.1rem;
  font-weight: 500;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.spinner {
  width: 24px;
  height: 24px;
  border: 3px solid #e5e5ea;
  border-top-color: #007aff;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}