:root{
    --primary:#0d6efd;
    --success:#198754;
    --danger:#dc3545;
    --dark:#212529;
    --light:#f8f9fa;
}

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

body{
    background:#f5f7fb;
    font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;
    min-height:100vh;
}

.navbar-brand{
    font-weight:700;
    letter-spacing:1px;
}

.main-container{
    padding:40px 0;
}

.card{
    border:none;
    border-radius:18px;
    overflow:hidden;
    background:#fff;
    box-shadow:0 10px 30px rgba(0,0,0,.08);
}

.card-header{
    background:var(--primary);
    color:#fff;
    font-size:20px;
    font-weight:600;
    padding:18px;
}

.balance-card{
    text-align:center;
    padding:30px;
}

.balance-value{
    font-size:42px;
    font-weight:700;
    color:var(--success);
}

.balance-label{
    font-size:14px;
    color:#777;
    text-transform:uppercase;
}

.form-control{
    border-radius:12px;
    height:50px;
}

.btn-search{
    height:50px;
    border-radius:12px;
    font-weight:600;
}

.table{
    font-size:14px;
}

.table thead{
    background:#0d6efd;
    color:white;
}

.table th{
    white-space:nowrap;
}

.table td{
    vertical-align:middle;
}

.section-title{
    font-size:22px;
    font-weight:700;
    margin-bottom:15px;
    color:#333;
}

.loading{
    display:none;
    text-align:center;
    padding:20px;
}

.spinner{
    width:50px;
    height:50px;
    border:4px solid #ddd;
    border-top:4px solid var(--primary);
    border-radius:50%;
    animation:spin 1s linear infinite;
    margin:auto;
}

@keyframes spin{
    100%{
        transform:rotate(360deg);
    }
}

.customer-info td:first-child{
    font-weight:600;
    width:250px;
}

.badge-success{
    background:#198754;
}

.badge-danger{
    background:#dc3545;
}

.footer{
    text-align:center;
    color:#777;
    padding:30px 0;
}

.search-box{
    max-width:600px;
    margin:auto;
}

.result-section{
    display:none;
    margin-top:30px;
}

.table-responsive{
    overflow-x:auto;
}

@media(max-width:768px){

    .balance-value{
        font-size:30px;
    }

    .card-header{
        font-size:18px;
    }

    .table{
        font-size:12px;
    }

    .customer-info td:first-child{
        width:120px;
    }
}