:root {
    --bg: #f3f6f8;
    --surface: #ffffff;
    --text: #1f2937;
    --muted: #6b7280;
    --line: #d1d5db;
    --brand: #0f766e;
    --danger: #b91c1c;
}

* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: "Segoe UI", Tahoma, sans-serif;
    background: linear-gradient(180deg, #eef7f6 0%, var(--bg) 320px);
    color: var(--text);
}
.container { max-width: 1180px; margin: 0 auto; padding: 20px; }
header { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 16px; }
header h1 { margin: 0 0 12px 0; font-size: 22px; }
nav { display: flex; gap: 10px; flex-wrap: wrap; }
nav a {
    text-decoration: none;
    color: #064e3b;
    padding: 7px 12px;
    border-radius: 8px;
    border: 1px solid #99f6e4;
    background: #ccfbf1;
}
main { margin-top: 16px; display: grid; gap: 16px; }
.card {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 16px;
}
h2, h3 { margin-top: 0; }
.grid { display: grid; gap: 12px; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); }
label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 4px; }
input, select, textarea, button {
    width: 100%;
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 9px 10px;
    font-size: 14px;
}
button, .btn {
    width: auto;
    background: var(--brand);
    color: #fff;
    border-color: var(--brand);
    cursor: pointer;
}
.btn-secondary { background: #374151; border-color: #374151; }
.btn-danger { background: var(--danger); border-color: var(--danger); }
.table-wrap { overflow: auto; }
table { width: 100%; border-collapse: collapse; min-width: 750px; }
th, td { border-bottom: 1px solid #e5e7eb; padding: 10px; text-align: left; vertical-align: top; }
th { font-size: 12px; text-transform: uppercase; color: var(--muted); }
.badge { display: inline-block; padding: 3px 8px; border-radius: 100px; font-size: 12px; color: #111827; background: #e5e7eb; }
.status-pill {
    display: inline-block;
    padding: 3px 10px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 600;
}
.status-paid {
    background: #16a34a;
    color: #ffffff;
    border: 1px solid #15803d;
}
.status-unpaid {
    background: #dc2626;
    color: #ffffff;
    border: 1px solid #b91c1c;
}
.kpi { font-size: 24px; font-weight: 700; }
.row { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.alert { padding: 10px 12px; border-radius: 8px; background: #fef3c7; border: 1px solid #fde68a; }
.small { color: var(--muted); font-size: 12px; }

@media (max-width: 700px) {
    .container { padding: 12px; }
    header, .card { border-radius: 10px; }
}