:root {
  --bg: #fafbfc;
  --text: #0a0e27;
  --muted: #718096;
  --brand: #10b981;
  --surface: #ffffff;
  --border: rgba(15, 23, 42, 0.08);
  --gradient: linear-gradient(135deg, #10b981 0%, #3b82f6 100%);
  --danger: #ef4444;
}

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

body {
  font-family: Inter, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.auth-wrap {
  max-width: 440px;
  margin: 48px auto;
  padding: 0 20px 48px;
}

.auth-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px;
  box-shadow: 0 16px 48px rgba(15, 23, 42, 0.08);
}

.auth-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
  text-decoration: none;
  color: var(--text);
  font-weight: 800;
}

.auth-logo img { width: 40px; height: 40px; border-radius: 10px; }

h1 { font-size: 28px; margin-bottom: 8px; }
.subtitle { color: var(--muted); margin-bottom: 24px; font-size: 15px; }

.tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 24px;
  background: #f1f5f9;
  padding: 4px;
  border-radius: 10px;
}

.tab {
  flex: 1;
  border: none;
  background: transparent;
  padding: 10px;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  color: var(--muted);
}

.tab.active {
  background: white;
  color: var(--text);
  box-shadow: 0 2px 8px rgba(15, 23, 42, 0.06);
}

.form-group { margin-bottom: 16px; }
label { display: block; font-weight: 600; margin-bottom: 6px; font-size: 14px; }

input {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 15px;
}

input:focus {
  outline: none;
  border-color: #3b82f6;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.btn-primary {
  width: 100%;
  border: none;
  border-radius: 10px;
  padding: 12px 16px;
  background: var(--gradient);
  color: white;
  font-weight: 700;
  font-size: 15px;
  cursor: pointer;
  margin-top: 8px;
}

.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; }

.message {
  margin-top: 16px;
  padding: 12px;
  border-radius: 10px;
  font-size: 14px;
  display: none;
}

.message.error { display: block; background: #fef2f2; color: #b91c1c; }
.message.success { display: block; background: #ecfdf5; color: #047857; }

.back-link {
  display: inline-block;
  margin-top: 20px;
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
}

.back-link:hover { color: var(--text); }

.panel { display: none; }
.panel.active { display: block; }

/* OAuth Divider */
.oauth-divider {
  display: flex;
  align-items: center;
  text-align: center;
  margin: 20px 0;
  color: var(--muted);
  font-size: 14px;
}

.oauth-divider::before,
.oauth-divider::after {
  content: '';
  flex: 1;
  border-bottom: 1px solid var(--border);
}

.oauth-divider:not(:empty)::before {
  margin-right: .5em;
}

.oauth-divider:not(:empty)::after {
  margin-left: .5em;
}

/* Google Button */
.btn-google {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  background: white;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 16px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}

.btn-google:hover {
  background: #f8fafc;
  border-color: #cbd5e1;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
  transform: translateY(-1px);
}

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