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

:root {
  --color-bg: #0a0a0f;
  --color-text: #fff;
  --color-text-muted: #9ca3af;
  --color-text-secondary: #6b7280;
  --color-card-bg: #111118;
  --color-card-border: #1e1e2e;
  --color-input-bg: #1a1a24;
  --color-input-border: #2a2a3a;
  --color-input-text: #fff;
  --color-input-placeholder: #4b5563;
  --color-btn-primary: #3b82f6;
  --color-btn-primary-hover: #2563eb;
  --color-btn-secondary-bg: #1a1a24;
  --color-btn-secondary-text: #9ca3af;
  --color-btn-secondary-hover-bg: #22222d;
  --color-btn-secondary-hover-text: #e5e7eb;
  --color-link: #3b82f6;
  --color-link-hover: #2563eb;
  --color-success-bg: rgba(34, 197, 94, 0.1);
  --color-success-border: rgba(34, 197, 94, 0.3);
  --color-success-text: #4ade80;
  --color-error-bg: rgba(239, 68, 68, 0.1);
  --color-error-border: rgba(239, 68, 68, 0.3);
  --color-error-text: #f87171;
  --color-spinner-border: rgba(255, 255, 255, 0.3);
  --color-spinner-text: #fff;
}

[data-theme="light"] {
  --color-bg: #f8fafc;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-text-secondary: #64748b;
  --color-card-bg: #fff;
  --color-card-border: #e2e8f0;
  --color-input-bg: #f1f5f9;
  --color-input-border: #cbd5e1;
  --color-input-text: #1e293b;
  --color-input-placeholder: #94a3b8;
  --color-btn-primary: #3b82f6;
  --color-btn-primary-hover: #2563eb;
  --color-btn-secondary-bg: #f1f5f9;
  --color-btn-secondary-text: #64748b;
  --color-btn-secondary-hover-bg: #e2e8f0;
  --color-btn-secondary-hover-text: #1e293b;
  --color-link: #3b82f6;
  --color-link-hover: #2563eb;
  --color-success-bg: rgba(34, 197, 94, 0.1);
  --color-success-border: rgba(34, 197, 94, 0.3);
  --color-success-text: #22c55e;
  --color-error-bg: rgba(239, 68, 68, 0.1);
  --color-error-border: rgba(239, 68, 68, 0.3);
  --color-error-text: #ef4444;
  --color-spinner-border: rgba(0, 0, 0, 0.3);
  --color-spinner-text: #1e293b;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.auth-container {
  width: 100%;
  max-width: 420px;
  padding: 24px;
}

.auth-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-card-border);
  border-radius: 16px;
  padding: 32px;
}

.auth-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 8px;
}

.auth-logo-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(135deg, #3b82f6, #8b5cf6);
  flex-shrink: 0;
}

.auth-logo-text {
  font-size: 24px;
  font-weight: 700;
}

.auth-subtitle {
  text-align: center;
  color: var(--color-text-secondary);
  font-size: 14px;
  margin-bottom: 24px;
}

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

.form-label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-muted);
  margin-bottom: 6px;
}

.form-input {
  width: 100%;
  background: var(--color-input-bg);
  border: 1px solid var(--color-input-border);
  border-radius: 10px;
  padding: 12px 16px;
  color: var(--color-input-text);
  font-size: 15px;
  outline: none;
  transition: border-color 0.2s;
}

.form-input:focus {
  border-color: var(--color-btn-primary);
}

.form-input::placeholder {
  color: var(--color-input-placeholder);
}

.form-row {
  display: flex;
  gap: 12px;
}

.form-row .form-group {
  flex: 1;
}

.btn {
  width: 100%;
  border: none;
  border-radius: 10px;
  padding: 12px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s, opacity 0.2s;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--color-btn-primary);
  color: #fff;
}

.btn-primary:hover:not(:disabled) {
  background: var(--color-btn-primary-hover);
}

.btn-secondary {
  background: var(--color-btn-secondary-bg);
  color: var(--color-btn-secondary-text);
  border: 1px solid var(--color-input-border);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--color-btn-secondary-hover-bg);
  color: var(--color-btn-secondary-hover-text);
}

.code-row {
  display: flex;
  gap: 10px;
  align-items: stretch;
}

.code-input {
  flex: 1;
  text-align: center;
  letter-spacing: 8px;
  font-size: 18px;
}

.code-btn {
  flex-shrink: 0;
  width: auto;
  padding: 12px 20px;
  font-size: 14px;
  white-space: nowrap;
}

.captcha-img-wrap {
  flex-shrink: 0;
  width: 150px;
  height: 50px;
  border-radius: 10px;
  overflow: hidden;
  background: var(--color-input-bg);
  border: 1px solid var(--color-input-border);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: border-color 0.2s;
}

.captcha-img-wrap:hover {
  border-color: var(--color-btn-primary);
}

.captcha-img-wrap svg {
  width: 100%;
  height: 100%;
}

.captcha-loading {
  color: var(--color-text-secondary);
  font-size: 12px;
  display: none;
}

.auth-options {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  font-size: 13px;
}

.auth-remember {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--color-text-muted);
  cursor: pointer;
}

.auth-remember input[type="checkbox"] {
  accent-color: var(--color-btn-primary);
  width: 16px;
  height: 16px;
}

.auth-link {
  color: var(--color-link);
  text-decoration: none;
}

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

.auth-footer {
  text-align: center;
  margin-top: 20px;
  color: var(--color-text-secondary);
  font-size: 13px;
}

.auth-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
}

.auth-tab {
  flex: 1;
  padding: 10px;
  text-align: center;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  background: var(--color-input-bg);
  color: var(--color-text-muted);
  border: 1px solid var(--color-input-border);
  transition: all 0.2s;
}

.auth-tab.active {
  background: var(--color-btn-primary);
  color: #fff;
  border-color: var(--color-btn-primary);
}

.error-msg {
  background: var(--color-error-bg);
  border: 1px solid var(--color-error-border);
  color: var(--color-error-text);
  font-size: 13px;
  border-radius: 8px;
  padding: 10px 14px;
  margin-bottom: 16px;
  display: none;
}

.error-msg.show {
  display: block;
}

.success-msg {
  background: var(--color-success-bg);
  border: 1px solid var(--color-success-border);
  color: var(--color-success-text);
  font-size: 13px;
  border-radius: 8px;
  padding: 10px 14px;
  margin-bottom: 16px;
  display: none;
}

.success-msg.show {
  display: block;
}

.spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid var(--color-spinner-border);
  border-top-color: var(--color-spinner-text);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
  vertical-align: middle;
  margin-right: 6px;
}

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