:root {
  --bg: #f5f6f8; --card: #fff; --text: #1c2333; --muted: #6b7280;
  --accent: #2652d9; --accent-h: #1d42b0; --border: #e3e6ec;
  --ok: #0d8a4f; --err: #c62828; --warn: #b45309;
}
* { box-sizing: border-box; }
body { margin: 0; font-family: -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg); color: var(--text); font-size: 15px; }
main { max-width: 1050px; margin: 24px auto; padding: 0 16px; }

.topnav { display: flex; gap: 4px; align-items: center; background: #101a33;
  padding: 0 16px; }
.topnav a { color: #cdd6ea; text-decoration: none; padding: 14px 12px; }
.topnav a:hover { color: #fff; }
.topnav .brand { font-weight: 700; color: #fff; font-size: 17px; }
.topnav .spacer { flex: 1; }

h1 { font-size: 22px; margin: 8px 0 16px; }
h2 { font-size: 17px; margin: 20px 0 10px; }

.card { background: var(--card); border: 1px solid var(--border);
  border-radius: 10px; padding: 18px 20px; margin-bottom: 16px; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px,1fr));
  gap: 14px; margin-bottom: 18px; }
.stat .label { color: var(--muted); font-size: 13px; }
.stat .value { font-size: 24px; font-weight: 700; margin-top: 4px; }

table { width: 100%; border-collapse: collapse; }
th { text-align: left; font-size: 12px; text-transform: uppercase;
  color: var(--muted); border-bottom: 2px solid var(--border); padding: 8px 10px; }
td { padding: 9px 10px; border-bottom: 1px solid var(--border); }
tr:hover td { background: #fafbfd; }
td.num, th.num { text-align: right; }

.btn { display: inline-block; background: var(--accent); color: #fff;
  border: 0; border-radius: 7px; padding: 8px 14px; font-size: 14px;
  cursor: pointer; text-decoration: none; }
.btn:hover { background: var(--accent-h); }
.btn.secondary { background: #fff; color: var(--text);
  border: 1px solid var(--border); }
.btn.secondary:hover { background: #f0f2f6; }
.btn.danger { background: #fff; color: var(--err); border: 1px solid #f2c6c6; }
.btn.small { padding: 4px 10px; font-size: 13px; }

.flash { padding: 10px 14px; border-radius: 8px; margin-bottom: 14px; }
.flash.ok { background: #e5f5ec; color: var(--ok); }
.flash.err { background: #fdeaea; color: var(--err); }

form.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px 18px; }
form .full { grid-column: 1 / -1; }
label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 4px; }
input[type=text], input[type=email], input[type=date], input[type=number],
input[type=password], select, textarea {
  width: 100%; padding: 8px 10px; border: 1px solid var(--border);
  border-radius: 7px; font-size: 14px; font-family: inherit; background:#fff; }
textarea { min-height: 70px; resize: vertical; }
.checkline { display: flex; align-items: center; gap: 8px; }
.checkline label { margin: 0; color: var(--text); font-size: 14px; }

.badge { display: inline-block; padding: 2px 9px; border-radius: 20px;
  font-size: 12px; font-weight: 600; }
.badge.draft { background: #eef0f4; color: var(--muted); }
.badge.open { background: #e7edfc; color: var(--accent); }
.badge.paid { background: #e5f5ec; color: var(--ok); }
.badge.cancelled { background: #fdeaea; color: var(--err); }
.badge.overdue { background: #fdf1e2; color: var(--warn); }

.toolbar { display: flex; gap: 10px; align-items: center; margin-bottom: 14px;
  flex-wrap: wrap; }
.toolbar form { display: flex; gap: 8px; }
.toolbar .spacer { flex: 1; }
.muted { color: var(--muted); }
.right { text-align: right; }
.actions { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.items-table input { min-width: 60px; }
.login-box { max-width: 360px; margin: 80px auto; }