* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
    background: #f4f6f8;
    color: #1f2937;
}

/* Login page */
.login-page { display: flex; align-items: center; justify-content: center; height: 100vh; }
.login-box {
    background: #fff; padding: 2.5rem; border-radius: 10px;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08); width: 320px;
}
.login-box h1 { font-size: 1.1rem; margin-bottom: 1.5rem; color: #111827; }
.login-box label { display: block; font-size: .85rem; margin: .75rem 0 .25rem; color: #374151; }
.login-box input { width: 100%; padding: .55rem; border: 1px solid #d1d5db; border-radius: 6px; }
.login-box button {
    margin-top: 1.25rem; width: 100%; padding: .6rem; border: none; border-radius: 6px;
    background: #2563eb; color: #fff; font-weight: 600; cursor: pointer;
}

/* App shell */
.app-shell { display: flex; min-height: 100vh; }
.sidebar {
    width: 240px; background: #111827; color: #d1d5db; flex-shrink: 0;
    padding-bottom: 2rem; overflow-y: auto;
}
.sidebar-brand { padding: 1.25rem 1rem; font-weight: 700; color: #fff; font-size: .95rem; border-bottom: 1px solid #1f2937; }
.sidebar nav { display: flex; flex-direction: column; }
.sidebar a {
    color: #d1d5db; text-decoration: none; padding: .55rem 1rem; font-size: .88rem;
}
.sidebar a:hover { background: #1f2937; color: #fff; }
.nav-group { padding: .8rem 1rem .2rem; font-size: .7rem; text-transform: uppercase; color: #6b7280; letter-spacing: .05em; }

.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.topbar {
    background: #fff; padding: .8rem 1.5rem; display: flex; justify-content: space-between;
    align-items: center; border-bottom: 1px solid #e5e7eb;
}
.page-title { font-weight: 700; font-size: 1.05rem; }
.user-menu { font-size: .85rem; color: #4b5563; }
.user-menu a { color: #2563eb; text-decoration: none; }

.content { padding: 1.5rem; }

/* KPI cards */
.kpi-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1rem; margin-bottom: 2rem; }
.kpi-card { background: #fff; padding: 1.2rem; border-radius: 8px; box-shadow: 0 1px 3px rgba(0,0,0,.06); }
.kpi-value { font-size: 1.6rem; font-weight: 700; color: #111827; }
.kpi-label { font-size: .8rem; color: #6b7280; margin-top: .25rem; }

/* Tables */
.data-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: 8px; overflow: hidden; }
.data-table th, .data-table td { padding: .6rem .8rem; border-bottom: 1px solid #f0f1f3; text-align: left; font-size: .87rem; }
.data-table th { background: #f9fafb; color: #374151; font-weight: 600; }

/* Filters */
.filter-bar { display: flex; gap: .6rem; align-items: center; margin-bottom: 1rem; flex-wrap: wrap; }
.filter-bar input, .filter-bar select {
    padding: .45rem .6rem; border: 1px solid #d1d5db; border-radius: 6px; font-size: .85rem;
}
.filter-bar button {
    padding: .45rem 1rem; background: #2563eb; color: #fff; border: none; border-radius: 6px; cursor: pointer;
}
.result-count { font-size: .8rem; color: #6b7280; margin-left: auto; }

/* Forms */
.form-box { background: #fff; padding: 1.5rem; border-radius: 8px; max-width: 480px; }
.form-box label { display: block; margin: .75rem 0 .25rem; font-size: .85rem; color: #374151; }
.form-box input[type=text], .form-box select {
    width: 100%; padding: .5rem; border: 1px solid #d1d5db; border-radius: 6px;
}
.form-box button {
    margin-top: 1.25rem; padding: .6rem 1.2rem; background: #2563eb; color: #fff;
    border: none; border-radius: 6px; cursor: pointer; font-weight: 600;
}
.form-box a { margin-left: 1rem; color: #6b7280; text-decoration: none; }

/* Badges */
.badge { padding: .15rem .5rem; border-radius: 12px; font-size: .75rem; font-weight: 600; }
.badge-vacant { background: #fef3c7; color: #92400e; }
.badge-occupied, .badge-owner_occupied { background: #d1fae5; color: #065f46; }
.badge-rented { background: #dbeafe; color: #1e40af; }
.badge-unpaid { background: #fee2e2; color: #991b1b; }
.badge-partially_paid { background: #fef3c7; color: #92400e; }
.badge-paid { background: #d1fae5; color: #065f46; }
.badge-overdue { background: #7f1d1d; color: #fecaca; }

/* Invoice detail */
.invoice-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 1.5rem; }
.invoice-meta { background: #fff; padding: 1.2rem; border-radius: 8px; margin-bottom: 1.2rem; }
.invoice-meta dl { display: grid; grid-template-columns: 160px 1fr; gap: .4rem .8rem; margin: 0; font-size: .88rem; }
.invoice-meta dt { color: #6b7280; }
.invoice-meta dd { margin: 0; font-weight: 600; }
.audit-table { font-size: .8rem; }
.section-title { font-size: .95rem; font-weight: 700; margin: 1.5rem 0 .6rem; color: #111827; }

/* Alerts */
.alert { padding: .7rem 1rem; border-radius: 6px; margin-bottom: 1rem; font-size: .88rem; }
.alert-success { background: #d1fae5; color: #065f46; }
.alert-error { background: #fee2e2; color: #991b1b; }