body {
    font-family: 'Segoe UI', Roboto, Arial, sans-serif;
    background-color: #f4f7fb;
    color: #333;
    margin: 0;
    padding: 50px 20px;
    text-align: center;
}

/* -------------------------------
   BOTONES
---------------------------------- */
button {
    padding: 12px 24px;
    font-size: 16px;
    background-color: #0057b8;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s ease;
}

button:hover {
    background-color: #003f8a;
}

/* -------------------------------
   FLASH MESSAGES PROFESIONALES
---------------------------------- */
.flash {
    display: flex;
    align-items: center;
    justify-content: center;
    max-width: 600px;
    margin: 0 auto 20px auto;
    padding: 16px 20px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    position: relative;
    animation: fadeIn 0.4s ease-out, fadeOut 0.5s ease-out 4s forwards;
}

/* Éxito */
.flash.success {
    background-color: #d1e7dd;
    color: #0f5132;
    border-left: 5px solid #198754;
}

/* Error */
.flash.error {
    background-color: #f8d7da;
    color: #842029;
    border-left: 5px solid #dc3545;
}

/* -------------------------------
   ANIMACIONES
---------------------------------- */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeOut {
    to {
        opacity: 0;
        transform: translateY(-10px);
        visibility: hidden;
        height: 0;
        margin: 0;
        padding: 0;
    }
}
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    max-width: 320px;
    padding: 14px 20px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 15px;
    z-index: 9999;
    color: #fff;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    animation: fadeIn 0.4s ease-out, fadeOut 0.5s ease-out 4.5s forwards;
}

/* TOAST de éxito */
.toast.success {
    background-color: #28a745;
}

/* TOAST de error */
.toast.error {
    background-color: #dc3545;
}
.device-table {
    width: 90%;
    margin: auto;
    border-collapse: collapse;
    font-size: 15px;
    background-color: white;
    box-shadow: 0 0 12px rgba(0,0,0,0.05);
    border-radius: 8px;
    overflow: hidden;
}

.device-table th, .device-table td {
    padding: 12px 14px;
    text-align: left;
    border-bottom: 1px solid #e5e7eb;
}

.device-table th {
    background-color: #1f2937;
    color: white;
}

.sim-status {
    font-weight: bold;
    padding: 4px 10px;
    border-radius: 6px;
}

.sim-status.used {
    background-color: #fee2e2;
    color: #b91c1c;
}

.sim-status.free {
    background-color: #dcfce7;
    color: #166534;
}

.signal-bars {
    width: 50px;
    height: 12px;
    background: repeating-linear-gradient(
        to right,
        #22c55e 0%,
        #22c55e calc(var(--level, 0) * 20%),
        #e5e7eb calc(var(--level, 0) * 20%),
        #e5e7eb 100%
    );
    border-radius: 3px;
}