:root {
    --bg:      #07090d;
    --surface: #0d1117;
    --card:    #111820;
    --border:  #1e2d3d;
    --accent:  #00d4ff;
    --accent2: #0055ff;
    --success: #00e676;
    --danger:  #ff4444;
    --text:    #e2e8f0;
    --muted:   #64748b;
  }

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

  body {
    background: var(--bg);
    color: var(--text);
    font-family: 'DM Sans', sans-serif;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem 1rem;
  }

  /* Grid background */
  body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image:
      linear-gradient(rgba(0,212,255,0.025) 1px, transparent 1px),
      linear-gradient(90deg, rgba(0,212,255,0.025) 1px, transparent 1px);
    background-size: 44px 44px;
    pointer-events: none;
    z-index: 0;
  }

  /* Glow orbs */
  body::after {
    content: '';
    position: fixed;
    width: 600px; height: 600px;
    background: radial-gradient(circle, rgba(0,85,255,0.08) 0%, transparent 70%);
    top: -100px; left: -100px;
    pointer-events: none;
    z-index: 0;
  }

  .glow-orb {
    position: fixed;
    width: 500px; height: 500px;
    background: radial-gradient(circle, rgba(0,212,255,0.06) 0%, transparent 70%);
    bottom: -100px; right: -100px;
    pointer-events: none;
    z-index: 0;
  }

  /* ── Wrapper ── */
  .auth-wrapper {
    position: relative;
    z-index: 1;
    width: 100%;
    max-width: 460px;
  }

  /* ── Logo ── */
  .brand {
    text-align: center;
    margin-bottom: 2rem;
    animation: fadeUp 0.5s ease both;
  }

  .brand-logo {
    font-family: 'Orbitron', monospace;
    font-weight: 900;
    font-size: 1.4rem;
    color: var(--accent);
    letter-spacing: 3px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.6rem;
    margin-bottom: 0.4rem;
  }

  .brand-sub {
    font-size: 0.78rem;
    color: var(--muted);
    letter-spacing: 1.5px;
    font-family: 'Orbitron', monospace;
  }

  /* ── Card ── */
  .auth-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 16px;
    overflow: hidden;
    position: relative;
    animation: fadeUp 0.55s ease 0.1s both;
  }

  .auth-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent), var(--accent2), transparent);
  }

  /* ── Tabs ── */
  .tabs {
    display: grid;
    grid-template-columns: 1fr 1fr;
    border-bottom: 1px solid var(--border);
  }

  .tab-btn {
    padding: 1rem;
    background: transparent;
    border: none;
    color: var(--muted);
    font-family: 'Orbitron', monospace;
    font-size: 0.7rem;
    letter-spacing: 2px;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
  }

  .tab-btn::after {
    content: '';
    position: absolute;
    bottom: -1px; left: 0; right: 0;
    height: 2px;
    background: var(--accent);
    transform: scaleX(0);
    transition: transform 0.2s ease;
  }

  .tab-btn.active {
    color: var(--accent);
  }

  .tab-btn.active::after {
    transform: scaleX(1);
  }

  /* ── Forms container ── */
  .forms-wrap {
    overflow: hidden;
    position: relative;
  }

  .form-panel {
    padding: 2rem;
    display: none;
    animation: fadeUp 0.35s ease both;
  }

  .form-panel.active { display: block; }

  /* Register panel scrollable */
  .form-panel.register-panel {
    max-height: 65vh;
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: var(--border) transparent;
  }

  .form-panel.register-panel::-webkit-scrollbar { width: 4px; }
  .form-panel.register-panel::-webkit-scrollbar-track { background: transparent; }
  .form-panel.register-panel::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
  }

  /* ── Section label ── */
  .section-label {
    font-family: 'Orbitron', monospace;
    font-size: 0.6rem;
    letter-spacing: 2.5px;
    color: var(--muted);
    margin: 1.5rem 0 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
  }

  .section-label::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--border);
  }

  .section-label:first-child { margin-top: 0; }

  /* ── Input group ── */
  .input-group {
    position: relative;
    margin-bottom: 1.1rem;
  }

  .input-group .icon {
    position: absolute;
    left: 0.9rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--muted);
    font-size: 0.9rem;
    pointer-events: none;
    transition: color 0.2s;
  }

  .input-group input {
    width: 100%;
    padding: 0.8rem 0.9rem 0.8rem 2.5rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text);
    font-family: 'DM Sans', sans-serif;
    font-size: 0.88rem;
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
  }

  .input-group input::placeholder {
    color: var(--muted);
    font-size: 0.82rem;
  }

  .input-group input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(0,212,255,0.08);
  }

  .input-group input:focus + .icon,
  .input-group input:focus ~ .icon {
    color: var(--accent);
  }

  /* icon is before input in DOM so use ~ sibling on focus from input */
  .input-group:focus-within .icon { color: var(--accent); }

  /* autofill */
  input:-webkit-autofill,
  input:-webkit-autofill:hover,
  input:-webkit-autofill:focus {
    -webkit-box-shadow: 0 0 0 1000px var(--surface) inset !important;
    -webkit-text-fill-color: var(--text) !important;
    caret-color: var(--text);
  }

  /* ── Two col grid ── */
  .input-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
  }
  
  .toggle-pw {
    position: absolute; right: 0.9rem; top: 50%;
    transform: translateY(-50%);
    color: var(--muted); cursor: pointer;
    font-size: 0.95rem; transition: color 0.2s;
    z-index: 1;
  }
  .toggle-pw:hover { color: var(--accent); }

  /* ── Forgot password ── */
  .forgot {
    text-align: right;
    margin: -0.5rem 0 1rem;
  }

  .forgot a {
    color: var(--muted);
    font-size: 0.78rem;
    text-decoration: none;
    transition: color 0.2s;
  }

  .forgot a:hover { color: var(--accent); }

  /* ── Submit button ── */
  .btn-submit {
    width: 100%;
    padding: 0.85rem;
    background: linear-gradient(135deg, var(--accent2), var(--accent));
    border: none;
    border-radius: 8px;
    color: #000;
    font-family: 'Orbitron', monospace;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 2px;
    cursor: pointer;
    transition: all 0.25s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 0.5rem;
  }

  .btn-submit:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0,212,255,0.3);
  }

  .btn-submit:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
  }

  /* ── Error message ── */
  .error-msg {
    background: rgba(255,68,68,0.08);
    border: 1px solid rgba(255,68,68,0.25);
    border-radius: 8px;
    color: var(--danger);
    font-size: 0.8rem;
    padding: 0.6rem 0.9rem;
    margin-bottom: 1rem;
    display: none;
    align-items: center;
    gap: 0.5rem;
  }

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

  /* ── Success message ── */
  .success-msg {
    background: rgba(0,230,118,0.08);
    border: 1px solid rgba(0,230,118,0.25);
    border-radius: 8px;
    color: var(--success);
    font-size: 0.8rem;
    padding: 0.6rem 0.9rem;
    margin-bottom: 1rem;
    display: none;
    align-items: center;
    gap: 0.5rem;
  }

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

  /* ── Footer note ── */
  .auth-footer {
    text-align: center;
    padding: 1.25rem;
    border-top: 1px solid var(--border);
    font-size: 0.75rem;
    color: var(--muted);
    font-family: 'Orbitron', monospace;
    letter-spacing: 1px;
  }

  /* ── Animations ── */
  @keyframes fadeUp {
    from { opacity: 0; transform: translateY(16px); }
    to   { opacity: 1; transform: translateY(0); }
  }

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

  @media (max-width: 480px) {
    .input-row { grid-template-columns: 1fr; }
    .form-panel { padding: 1.5rem; }
  }