:root {
      --bg: #f7f7f8;
      --card: #ffffff;
      --text: #0f172a;
      --muted: #64748b;
      --primary: #111827;
      --ring: rgba(2,132,199,0.35);
      --border: #e5e7eb;
      /* Cambia esta URL por la foto que quieras mostrar a la izquierda */
      --side-photo: url('../img/cyber.png');
    }

    * { box-sizing: border-box; }
    html, body { height: 100%; }
    body {
      margin: 0;
      font-family: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, 'Helvetica Neue', Arial, sans-serif;
      color: var(--text);
      background: linear-gradient(180deg, #fafafa, #f3f4f6);
    }

    /* NAVBAR */
    .navbar { position: sticky; top: 0; width: 100%; backdrop-filter: saturate(180%) blur(10px); background: rgba(255,255,255,0.7); border-bottom: 1px solid var(--border); z-index: 50; }
    .nav-inner { max-width: 1100px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; padding: 14px 20px; }
    .brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: inherit; }
    .brand-logo { width: 28px; height: 28px; border-radius: 8px; background: #111827; display: grid; place-items: center; color: white; font-size: 14px; font-weight: 700; letter-spacing: -0.02em; }
    .brand-name { font-weight: 700; letter-spacing: -0.01em; }
    .nav-links { display: flex; gap: 18px; }
    .nav-links a { color: var(--muted); text-decoration: none; font-size: 14px; }
    .nav-links a:hover { color: var(--text); }

    /* LAYOUT */
    .wrapper { max-width: 1100px; margin: 28px auto; display: grid; grid-template-columns: 1.1fr 1fr; gap: 28px; padding: 0 20px; }

    /* LEFT PHOTO PANEL */
    .side-photo { position: relative; border-radius: 20px; overflow: hidden; min-height: 520px; background: #0b1220; box-shadow: 0 10px 30px rgba(0,0,0,0.08); isolation: isolate; }
    .side-photo::before { content: ""; position: absolute; inset: 0; background-image: var(--side-photo); background-size: cover; background-position: center; filter: saturate(1) contrast(1.05); z-index: -1; transform: scale(1.02); }
    .side-overlay { position: absolute; inset: 0; background: linear-gradient(120deg, rgba(0,0,0,0.55), rgba(0,0,0,0.15)); }
    .side-content { position: absolute; inset: 0; display: grid; place-items: end start; padding: 24px; color: white; }
    .side-badge { display: inline-flex; align-items: center; gap: 8px; padding: 6px 10px; border-radius: 9999px; background: rgba(255,255,255,0.1); font-size: 12px; backdrop-filter: blur(4px); }
    .side-title { margin-top: 10px; font-weight: 700; font-size: 28px; letter-spacing: -0.02em; }
    .side-sub { margin-top: 6px; color: rgba(255,255,255,0.85); font-size: 14px; max-width: 55ch; }

    /* CARD (SIGNUP) */
    .card { background: var(--card); border: 1px solid var(--border); border-radius: 20px; padding: 28px; align-self: center; box-shadow: 0 10px 30px rgba(2,6,23,0.05); }
    .card h1 { font-size: 28px; margin: 6px 0 6px; letter-spacing: -0.02em; }
    .card p { color: var(--muted); font-size: 14px; margin: 0 0 18px; }

    .btn-google { width: 100%; display: inline-flex; align-items: center; justify-content: center; gap: 10px; border: 1px solid var(--border); background: white; padding: 12px 16px; border-radius: 12px; font-weight: 600; cursor: pointer; text-decoration: none; color: #111827; transition: transform .04s ease, box-shadow .15s ease, border-color .15s ease; box-shadow: 0 1px 0 rgba(17,24,39,0.04); }
    .btn-google:hover { border-color: #d1d5db; box-shadow: 0 8px 20px rgba(17,24,39,0.06); }
    .btn-google:active { transform: translateY(1px); }
    .g-icon { width: 20px; height: 20px; display: inline-block; }

    .divider { display: flex; align-items: center; gap: 12px; margin: 18px 0; color: var(--muted); font-size: 12px; }
    .divider::before, .divider::after { content: ""; height: 1px; background: var(--border); flex: 1; }

    .grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
    .form-group { margin-bottom: 12px; }
    label { display: block; font-size: 13px; color: #111827; margin-bottom: 6px; }
    input[type="text"], input[type="email"], input[type="password"] { width: 100%; padding: 12px 14px; border-radius: 12px; border: 1px solid var(--border); outline: none; font-size: 14px; background: white; transition: border-color .15s ease, box-shadow .15s ease; }
    input:focus { border-color: #93c5fd; box-shadow: 0 0 0 4px var(--ring); }

    .pw-wrap { position: relative; }
    .toggle-pw { position: absolute; right: 10px; top: 50%; transform: translateY(-50%); border: 0; background: transparent; cursor: pointer; font-size: 12px; color: var(--muted); }

    .strength { height: 8px; border-radius: 9999px; background: #f1f5f9; overflow: hidden; margin-top: 8px; }
    .strength > div { height: 100%; width: 0%; background: #10b981; transition: width .25s ease; }
    .hint { font-size: 12px; color: var(--muted); margin-top: 6px; }
    .error { font-size: 12px; color: #b91c1c; margin-top: 6px; display: none; }

    .terms { display: flex; gap: 10px; align-items: flex-start; font-size: 13px; color: var(--muted); margin: 6px 0 10px; }
    .terms a { color: #111827; text-decoration: none; }
    .terms a:hover { text-decoration: underline; }

    .btn-primary { width: 100%; border: 0; background: #111827; color: white; padding: 12px 16px; border-radius: 12px; font-weight: 600; cursor: pointer; transition: transform .04s ease, box-shadow .15s ease, opacity .15s ease; }
    .btn-primary:hover { box-shadow: 0 10px 20px rgba(17,24,39,0.18); }
    .btn-primary:active { transform: translateY(1px); }
    .btn-primary[disabled] { opacity: 0.6; cursor: not-allowed; }

    .help { margin-top: 10px; font-size: 12px; color: var(--muted); }
    .help a { color: #111827; text-decoration: none; }
    .help a:hover { text-decoration: underline; }

    footer { margin: 30px auto 40px; max-width: 1100px; padding: 12px 20px; color: var(--muted); font-size: 12px; display: flex; align-items: center; justify-content: space-between; border-top: 1px solid var(--border); }
    .foot-links { display: flex; gap: 14px; }
    .foot-links a { color: var(--muted); text-decoration: none; }
    .foot-links a:hover { color: var(--text); }

    @media (max-width: 980px) {
      .wrapper { grid-template-columns: 1fr; }
      .side-photo { min-height: 260px; }
      .grid-2 { grid-template-columns: 1fr; }
    }