:root {
  --blue:    #0099FF;
  --card-bg: #ffffff;
  --card-border: #e5e7eb;
  --text:    #111827;
  --text-sm: #6b7280;
  --input-bg: #f9fafb;
}
[data-theme="dark"] {
  --card-bg:     #1a2235;
  --card-border: #2d3748;
  --text:        #f1f5f9;
  --text-sm:     #94a3b8;
  --input-bg:    #0f1623;
}

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

/* ── Brand logo light/dark swap ──────────────────────────────────────────── */
.brand { display: flex; align-items: center; }
.brand img { height: 32px; width: auto; }
.logo-light { display: none; }
.logo-dark  { display: block; }
[data-theme="light"] .logo-dark  { display: none; }
[data-theme="light"] .logo-light { display: block; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: #0a1628;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.login-card {
  background: var(--card-bg);
  border-radius: 14px;
  padding: 40px;
  width: 100%;
  max-width: 400px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4);
}

.login-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 28px;
}

.brand {
  font-size: 22px;
  font-weight: 800;
  color: var(--blue);
  letter-spacing: 3px;
}

.theme-toggle {
  background: none;
  border: 1px solid var(--card-border);
  border-radius: 6px;
  padding: 5px 9px;
  font-size: 14px;
  cursor: pointer;
  color: var(--text-sm);
}
.theme-toggle:hover { border-color: var(--blue); color: var(--blue); }

.login-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 6px;
}

.login-sub {
  font-size: 14px;
  color: var(--text-sm);
  margin-bottom: 28px;
}

.btn-group { display: flex; flex-direction: column; gap: 0; }

.btn-microsoft,
.btn-google {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  width: 100%;
  padding: 13px 20px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: opacity 0.15s;
}
.btn-microsoft:hover,
.btn-google:hover { opacity: 0.88; }

.btn-microsoft {
  background: #0078d4;
  color: #ffffff;
  border: none;
  margin-bottom: 12px;
}

.btn-google {
  background: #ffffff;
  color: #3c4043;
  border: 1px solid #dadce0;
}
[data-theme="dark"] .btn-google {
  background: #1e293b;
  color: var(--text);
  border-color: var(--card-border);
}

.divider {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 4px 0 12px;
  color: var(--text-sm);
  font-size: 12px;
}
.divider::before,
.divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--card-border);
}

.alert-error {
  background: #fef2f2;
  border: 1px solid #fca5a5;
  color: #991b1b;
  padding: 10px 14px;
  border-radius: 6px;
  font-size: 13px;
  margin-bottom: 20px;
}
[data-theme="dark"] .alert-error {
  background: #3b0f0f;
  border-color: #7f1d1d;
  color: #fca5a5;
}

.login-help {
  margin-top: 24px;
  text-align: center;
  font-size: 13px;
  color: var(--text-sm);
}
.login-help a { color: var(--blue); text-decoration: none; }
.login-help a:hover { text-decoration: underline; }