:root {
    --primary: #25D366;
    --primary-dark: #128C7E;
    --bg: #f0f2f5;
    --card-bg: #ffffff;
    --text: #111b21;
    --text-muted: #667781;
    --border: #e9edef;
    --error: #f15c6d;
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: -apple-system, sans-serif; }
body { background-color: var(--bg); color: var(--text); }

header {
    background-color: var(--primary-dark);
    color: white; padding: 1rem 2rem; display: flex; justify-content: space-between; align-items: center;
}
.header-right { display: flex; align-items: center; gap: 1rem; }
.logo { font-size: 1.5rem; font-weight: bold; }
.badge { padding: 0.25rem 0.75rem; border-radius: 9999px; font-size: 0.875rem; font-weight: 500; }
.badge.connected { background-color: var(--primary); color: white; }
.badge.disconnected { background-color: var(--error); color: white; }

.container { max-width: 1200px; margin: 2rem auto; padding: 0 1rem; }
.card { background: var(--card-bg); border-radius: 8px; box-shadow: 0 1px 3px rgba(0,0,0,0.1); padding: 1.5rem; margin-bottom: 1.5rem; }
.login-card, .qr-card { max-width: 400px; margin: 2rem auto; text-align: center; }

form { display: flex; flex-direction: column; gap: 1rem; margin-top: 1.5rem; }
input, select { padding: 0.75rem; border: 1px solid var(--border); border-radius: 4px; font-size: 1rem; }
button { background-color: var(--primary); color: white; border: none; padding: 0.75rem 1.5rem; border-radius: 4px; font-size: 1rem; cursor: pointer; }
button:hover { background-color: var(--primary-dark); }
button:disabled { background-color: var(--text-muted); cursor: not-allowed; }

.metrics-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1.5rem; margin-bottom: 1.5rem; }
.metric-card { background: var(--card-bg); padding: 1.5rem; border-radius: 8px; text-align: center; }
.metric-card h3 { color: var(--text-muted); font-size: 0.875rem; text-transform: uppercase; margin-bottom: 0.5rem; }
.metric-card .value { font-size: 2rem; font-weight: bold; color: var(--primary-dark); }

.table-controls { display: flex; gap: 1rem; margin-bottom: 1rem; }
.table-controls input { flex: 1; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 1rem; text-align: left; border-bottom: 1px solid var(--border); }
th { color: var(--text-muted); font-weight: 500; }

.status-sent { color: var(--primary); }
.status-failed { color: var(--error); }
.status-queued { color: #f5a623; }
.status-sending { color: #4a90e2; }
.btn-retry { background-color: var(--text-muted); padding: 0.5rem 1rem; font-size: 0.875rem; }
.btn-retry:hover { background-color: var(--text); }
.pagination { display: flex; justify-content: center; align-items: center; gap: 1rem; margin-top: 1.5rem; }
.error { color: var(--error); margin-top: 1rem; font-size: 0.875rem; }
#qr-code img { margin: 1rem auto; }