311 /workspace/bulkmailer/static/css/app.css
---root vars---
/* ============================================================
   Bulk Gmail Mailer — Design System
   Professional admin UI: dark sidebar, light content, responsive
   ============================================================ */
:root {
  --sidebar-w: 240px;
  --bg: #f4f6fa;
  --surface: #ffffff;
  --border: #e3e8f0;
  --text: #1e2536;
  --muted: #6b7590;
  --primary: #2563eb;
  --primary-dk: #1e40af;
  --primary-lt: #eff6ff;
  --green: #16a34a;
  --green-lt: #f0fdf4;
  --red: #dc2626;
  --red-lt: #fef2f2;
  --amber: #d97706;
  --amber-lt: #fffbeb;
  --violet: #7c3aed;
  --violet-lt: #f5f3ff;
  --sidebar-bg: #101828;
  --sidebar-text: #98a2b3;
  --sidebar-active: #1f2a44;
  --radius: 10px;
  --shadow: 0 1px 3px rgba(16, 24, 40, .08), 0 1px 2px rgba(16, 24, 40, .04);
  --shadow-lg: 0 10px 30px rgba(16, 24, 40, .14);
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; }
body {
  font: 14px/1.55 -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg); color: var(--text);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
h1 { font-size: 22px; font-weight: 700; letter-spacing: -.02em; }
h2 { font-size: 17px; font-weight: 650; }
h3 { font-size: 14.5px; font-weight: 650; color: var(--text); }
code, .mono { font-family: var(--mono); font-size: 12.5px; background: #eef1f6; padding: 1px 6px; border-radius: 5px; }
hr { border: none; border-top: 1px solid var(--border); margin: 14px 0; }

/* ---------- Layout ---------- */
.layout { display: flex; min-height: 100vh; }
.sidebar {
  width: var(--sidebar-w); background: var(--sidebar-bg); color: var(--sidebar-text);
  position: fixed; inset: 0 auto 0 0; display: flex; flex-direction: column; z-index: 50;
  transition: transform .22s ease;
}
.sidebar .brand {
  display: flex; align-items: center; gap: 10px; padding: 18px 18px 14px;
  color: #fff; font-weight: 700; font-size: 15.5px; letter-spacing: -.01em;
}
.brand-badge {
  width: 30px; height: 30px; border-radius: 8px; flex: none;
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  display: grid; place-items: center; font-size: 15px; color: #fff;
}
.sidebar nav { flex: 1; overflow-y: auto; padding: 6px 10px 10px; }
.nav-section { font-size: 10.5px; font-weight: 700; text-transform: uppercase; letter-spacing: .09em; color: #5d6b85; padding: 14px 10px 5px; }
.nav-link {
  display: flex; align-items: center; gap: 10px; padding: 8px 10px; border-radius: 8px;
  color: var(--sidebar-text); font-weight: 500; font-size: 13.5px; cursor: pointer; margin: 1px 0;
  border: none; background: none; width: 100%; text-align: left; text-decoration: none;
}
.nav-link:hover { background: #182238; color: #d0d5dd; text-decoration: none; }
.nav-link.active { background: var(--sidebar-active); color: #fff; box-shadow: inset 2px 0 0 var(--primary); }
.nav-link .ico { width: 18px; text-align: center; flex: none; font-size: 14px; opacity: .95; }
.sidebar .foot { padding: 12px 14px; border-top: 1px solid #1c2740; font-size: 12px; }
.foot .user-line { color: #d0d5dd; display: flex; align-items: center; gap: 8px; }
.foot button { margin-top: 8px; }

.main { flex: 1; margin-left: var(--sidebar-w); display: flex; flex-direction: column; min-width: 0; }
main#content { margin-left: var(--sidebar-w); display: block; min-width: 0; }
@media(max-width:900px){ main#content { margin-left: 0; } }
.topbar {
  position: sticky; top: 0; z-index: 40; background: rgba(244,246,250,.92); backdrop-filter: blur(6px);
