/* =========================================================
   style.css — Diseño moderno, inspirado en Apple / Stripe / Cloudflare
   Sin frameworks. CSS puro con variables y dark mode automático.
   ========================================================= */

:root {
    --color-bg: #f5f5f7;
    --color-surface: #ffffff;
    --color-text: #1d1d1f;
    --color-text-muted: #6e6e73;
    --color-border: #e5e5ea;
    --color-primary: #0071e3;
    --color-primary-hover: #0077ed;
    --color-danger: #ff3b30;
    --color-success: #34c759;
    --shadow-soft: 0 1px 3px rgba(0,0,0,0.06), 0 8px 24px rgba(0,0,0,0.06);
    --radius-lg: 18px;
    --radius-md: 12px;
    --radius-sm: 8px;
    --font-main: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --ancho-maximo: 1060px;
}

@media (prefers-color-scheme: dark) {
    :root {
        --color-bg: #000000;
        --color-surface: #1c1c1e;
        --color-text: #f5f5f7;
        --color-text-muted: #9a9a9e;
        --color-border: #2c2c2e;
        --color-primary: #0a84ff;
        --color-primary-hover: #3ba0ff;
        --shadow-soft: 0 1px 3px rgba(0,0,0,0.4), 0 8px 24px rgba(0,0,0,0.4);
    }
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: var(--font-main);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.contenedor {
    max-width: var(--ancho-maximo);
    width: 100%;
    margin: 0 auto;
    padding: 32px 20px 80px;
}

.encabezado {
    text-align: center;
    margin-bottom: 32px;
}

.logo-empresa {
    display: block;
    max-width: 320px;
    width: 100%;
    height: auto;
    margin: 0 auto 20px;
}

@media (max-width: 640px) {
    .logo-empresa {
        max-width: 240px;
    }
}

.encabezado h1 {
    font-size: 26px;
    font-weight: 700;
    margin: 12px 0 4px;
}

.encabezado p {
    color: var(--color-text-muted);
    font-size: 15px;
    margin: 0;
}

.card {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-soft);
    padding: 28px;
    margin-bottom: 24px;
    border: 1px solid var(--color-border);
}

.card h2 {
    font-size: 18px;
    font-weight: 600;
    margin-top: 0;
    margin-bottom: 18px;
}

.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

@media (max-width: 640px) {
    .grid-2 { grid-template-columns: 1fr; }
}

.campo { margin-bottom: 16px; }

.campo label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--color-text-muted);
}

.campo input,
.campo textarea,
.campo select {
    width: 100%;
    padding: 11px 14px;
    font-size: 15px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    background: var(--color-bg);
    color: var(--color-text);
    font-family: var(--font-main);
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.campo input:focus,
.campo textarea:focus,
.campo select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(10,132,255,0.15);
}

.campo .error {
    color: var(--color-danger);
    font-size: 12px;
    margin-top: 4px;
    display: none;
}

.campo.campo-invalido input,
.campo.campo-invalido textarea {
    border-color: var(--color-danger);
}

.campo.campo-invalido .error { display: block; }

.documento-legal {
    max-height: 420px;
    overflow-y: auto;
    padding: 20px;
    background: var(--color-bg);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    font-size: 14px;
    /* Limita el ancho de línea de lectura aunque el contenedor
       general sea más ancho, para que el texto legal no quede
       incómodo de leer en pantallas grandes */
    max-width: 780px;
    margin: 0 auto;
}

.documento-legal h3 {
    text-align: center;
    font-size: 17px;
    margin-bottom: 4px;
}

.documento-legal .subtitulo {
    text-align: center;
    color: var(--color-text-muted);
    font-size: 13px;
    margin-bottom: 18px;
}

.documento-legal p { margin: 10px 0; }

.documento-legal .seccion-titulo {
    font-weight: 700;
    margin-top: 20px;
    font-size: 13px;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--color-text-muted);
}

.checkbox-lista { margin-top: 8px; }

.checkbox-item {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 10px 0;
    border-bottom: 1px solid var(--color-border);
}

.checkbox-item:last-child { border-bottom: none; }

.checkbox-item input[type="checkbox"] {
    width: 20px;
    height: 20px;
    margin-top: 2px;
    accent-color: var(--color-primary);
    flex-shrink: 0;
}

.checkbox-item label {
    font-size: 14px;
    cursor: pointer;
}

.firma-contenedor {
    border: 2px dashed var(--color-border);
    border-radius: var(--radius-md);
    background: #fff;
    touch-action: none;
}

#canvasFirma {
    width: 100%;
    height: 200px;
    display: block;
    cursor: crosshair;
    border-radius: var(--radius-md);
}

.firma-botones {
    display: flex;
    gap: 10px;
    margin-top: 12px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 22px;
    font-size: 15px;
    font-weight: 600;
    border-radius: 980px;
    border: none;
    cursor: pointer;
    transition: transform 0.1s ease, opacity 0.15s ease;
    font-family: var(--font-main);
}

.btn:active { transform: scale(0.97); }

.btn-primario {
    background: var(--color-primary);
    color: #fff;
    width: 100%;
    padding: 15px;
    font-size: 16px;
}

.btn-primario:hover { background: var(--color-primary-hover); }

.btn-primario:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.btn-secundario {
    background: var(--color-border);
    color: var(--color-text);
}

.btn-secundario:hover { opacity: 0.85; }

.alerta {
    padding: 14px 16px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    margin-bottom: 20px;
}

.alerta-error {
    background: rgba(255,59,48,0.1);
    color: var(--color-danger);
    border: 1px solid rgba(255,59,48,0.25);
}

.alerta-exito {
    background: rgba(52,199,89,0.1);
    color: var(--color-success);
    border: 1px solid rgba(52,199,89,0.25);
}

.pie {
    text-align: center;
    color: var(--color-text-muted);
    font-size: 12px;
    margin-top: 40px;
}

.spinner {
    width: 18px; height: 18px;
    border: 2px solid rgba(255,255,255,0.4);
    border-top-color: #fff;
    border-radius: 50%;
    animation: girar 0.7s linear infinite;
    display: none;
}

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