:root {
  --sidebar-w: 240px;
  --smm-bg: #f4f6fb;
  --smm-sidebar: #1b2a4a;
  --smm-accent: #4f7cff;
  --smm-border: #e3e8f0;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--smm-bg);
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  color: #1c2434;
}
.app-shell { display: flex; min-height: 100vh; }

/* Sidebar */
.sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  background: linear-gradient(180deg, #1b2a4a 0%, #14203c 100%);
  color: #cbd7ec;
  display: flex;
  flex-direction: column;
  position: sticky;
  top: 0;
  height: 100vh;
}
.sidebar .brand {
  display: flex; align-items: center; gap: .6rem;
  padding: 1.1rem 1.2rem; font-weight: 700; color: #fff; font-size: 1.05rem;
}
.sidebar .brand i { color: var(--smm-accent); font-size: 1.3rem; }
.sidebar nav { flex: 1; padding: .5rem .75rem; }
.sidebar .nav-link {
  color: #cbd7ec; border-radius: .5rem; padding: .6rem .85rem;
  display: flex; align-items: center; gap: .6rem; margin-bottom: .2rem;
}
.sidebar .nav-link:hover { background: rgba(255,255,255,.06); color: #fff; }
.sidebar .nav-link.active { background: var(--smm-accent); color: #fff; font-weight: 600; }
.sidebar .nav-link i { width: 1.2rem; text-align: center; }
.sidebar-foot { padding: 1rem; border-top: 1px solid rgba(255,255,255,.08); }

/* Main */
.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.topbar {
  background: #fff; border-bottom: 1px solid var(--smm-border);
  padding: .9rem 1.4rem;
}
.content { padding: 1.4rem; flex: 1; }

/* Cards */
.panel-card {
  border: 1px solid var(--smm-border);
  border-radius: .9rem;
  box-shadow: 0 2px 6px rgba(23,43,99,.05);
  background: #fff;
  overflow: hidden;
}
.panel-card .card-header {
  background: #fafbfe; border-bottom: 1px solid var(--smm-border);
  font-weight: 600; padding: .8rem 1rem;
}
.panel-card .card-body { padding: 1rem; }

/* Stat cards */
.stat-card {
  background: #fff; border: 1px solid var(--smm-border); border-radius: .9rem;
  padding: 1rem 1.1rem; display: flex; align-items: center; gap: 1rem;
  box-shadow: 0 2px 6px rgba(23,43,99,.05);
}
.panel-balance-card {
  background: #fff; border: 1px solid var(--smm-border); border-radius: .9rem;
  padding: 1rem 1.1rem; box-shadow: 0 2px 6px rgba(23,43,99,.05); height: 100%;
}
.balance-amount { font-size: 1.35rem; font-weight: 700; line-height: 1.2; color: #1c2434; }
.stat-icon { font-size: 1.6rem; color: var(--smm-accent); width: 3rem; height: 3rem;
  display: flex; align-items: center; justify-content: center; background: #eef2ff; border-radius: .75rem; }
.stat-value { font-size: 1.6rem; font-weight: 700; line-height: 1; }
.stat-label { color: #6b7688; font-size: .85rem; }

/* Campaign row */
.campaign-row { padding: .7rem 0; border-bottom: 1px dashed var(--smm-border); }
.campaign-row:last-child { border-bottom: 0; }

/* Login */
.login-bg { min-height: 100vh; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, #1b2a4a 0%, #2a3f6b 100%); padding: 1rem; }
.login-card { width: 100%; max-width: 380px; border-radius: 1rem; border: 0; }

/* Buttons */
.btn-primary { background: var(--smm-accent); border-color: var(--smm-accent); }
.btn-primary:hover { background: #3e67e0; border-color: #3e67e0; }

/* Responsive */
@media (max-width: 768px) {
  .app-shell { flex-direction: column; }
  .sidebar { width: 100%; height: auto; position: static; flex-direction: row; flex-wrap: wrap; align-items: center; }
  .sidebar .brand { flex: 1; }
  .sidebar nav { display: flex; flex-wrap: wrap; gap: .2rem; padding: .4rem; }
  .sidebar .nav-link { margin: 0; padding: .45rem .7rem; }
  .sidebar-foot { display: none; }
  .topbar { padding: .7rem 1rem; }
  .content { padding: 1rem; }
}