:root{
      --bg1:#0f172a;         /* slate-900 */
      --bg2:#111827;         /* gray-900  */
      --card:#0b1220cc;      /* glass */
      --border:rgba(255,255,255,.12);
      --text:#e5e7eb;        /* gray-200 */
      --muted:#94a3b8;       /* slate-400 */
      --accent:#6366f1;      /* indigo-500 */
      --accent2:#22c55e;     /* green-500 (hover/ok) */
      --danger:#ef4444;
      --shadow: 0 20px 60px rgba(0,0,0,.45);
      --radius: 16px;
    }

    *{ box-sizing:border-box; }
    body{
      margin:0;
      min-height:100vh;
      display:flex;
      align-items:center;
      justify-content:center;
      font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial;
      color:var(--text);
      background:
        radial-gradient(1000px 600px at 20% 10%, rgba(99,102,241,.35), transparent 60%),
        radial-gradient(900px 500px at 80% 40%, rgba(34,197,94,.25), transparent 55%),
        linear-gradient(180deg, var(--bg1), var(--bg2));
      padding:24px;
    }

    .login-wrap{
      width:100%;
      max-width:420px;
    }

    .card{
      background: var(--card);
      backdrop-filter: blur(10px);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      box-shadow: var(--shadow);
      padding: 28px;
      position:relative;
      overflow:hidden;
    }

    .card:before{
      content:"";
      position:absolute;
      inset:-2px;
      background: linear-gradient(120deg, rgba(99,102,241,.35), rgba(34,197,94,.20), transparent 60%);
      filter: blur(20px);
      opacity:.35;
      pointer-events:none;
    }

    .card > *{ position:relative; }

    .brand{
      display:flex;
      align-items:center;
      gap:12px;
      margin-bottom:18px;
    }
    .logo{
      width:44px;height:44px;
      border-radius:14px;
      background: linear-gradient(135deg, rgba(99,102,241,.9), rgba(34,197,94,.75));
      display:grid;
      place-items:center;
      box-shadow: 0 10px 25px rgba(99,102,241,.25);
      font-weight:800;
      color:white;
      letter-spacing:.5px;
    }
    h1{
      font-size:22px;
      margin:0;
      line-height:1.1;
    }
    .subtitle{
      margin:4px 0 0 0;
      color:var(--muted);
      font-size:13px;
    }

    form{
      display:flex;
      flex-direction:column;
      gap:14px;
      margin-top:14px;
    }

    label{
      font-size:13px;
      color:var(--muted);
      margin-bottom:6px;
      display:block;
    }

    .field{
      display:flex;
      flex-direction:column;
    }

    input{
      width:100%;
      padding: 12px 12px;
      border-radius: 12px;
      border: 1px solid var(--border);
      background: rgba(2,6,23,.35);
      color: var(--text);
      outline:none;
      transition: border-color .15s ease, box-shadow .15s ease, transform .05s ease;
    }

    input::placeholder{ color: rgba(148,163,184,.7); }

    input:focus{
      border-color: rgba(99,102,241,.65);
      box-shadow: 0 0 0 4px rgba(99,102,241,.18);
    }

    .row{
      display:flex;
      align-items:center;
      justify-content:space-between;
      gap:12px;
      margin-top:2px;
    }

    .remember{
      display:flex;
      align-items:center;
      gap:8px;
      color:var(--muted);
      font-size:13px;
      user-select:none;
    }
    .remember input{
      width:16px;height:16px;
      margin:0;
      box-shadow:none;
    }

    .link{
      color: rgba(99,102,241,.9);
      text-decoration:none;
      font-size:13px;
    }
    .link:hover{ text-decoration:underline; }

    button{
      margin-top:10px;
      width:100%;
      padding: 12px 14px;
      border-radius: 12px;
      border: none;
      cursor:pointer;
      font-weight:700;
      color:white;
      background: linear-gradient(135deg, rgba(99,102,241,1), rgba(79,70,229,1));
      box-shadow: 0 14px 35px rgba(99,102,241,.25);
      transition: transform .08s ease, filter .15s ease, box-shadow .15s ease;
    }
    button:hover{
      filter: brightness(1.05);
      box-shadow: 0 18px 45px rgba(99,102,241,.32);
    }
    button:active{ transform: translateY(1px); }

    .foot{
      margin-top:14px;
      text-align:center;
      color:var(--muted);
      font-size:12px;
    }

    /* Mensajes (si ya usas un alertBox, aplica esta clase) */
    .alert{
      display:none;
      padding:10px 12px;
      border-radius:12px;
      border:1px solid rgba(239,68,68,.35);
      background: rgba(239,68,68,.12);
      color: #fecaca;
      font-size:13px;
      margin-top:12px;
    }
    .alert.show{ display:block; }