:root{
  --primary:#2563eb;--primary-dark:#1d4ed8;--accent:#f59e0b;
  --success:#16a34a;--danger:#dc2626;--warn:#d97706;
  --bg:#f8fafc;--card:#fff;--text:#1e293b;--muted:#64748b;
  --border:#e2e8f0;--radius:10px;--shadow:0 2px 8px rgba(0,0,0,.08);
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:'Segoe UI',system-ui,sans-serif;background:var(--bg);color:var(--text);font-size:15px}

/* NAV */
.navbar{display:flex;align-items:center;justify-content:space-between;
  padding:0 24px;height:60px;background:var(--primary);color:#fff;
  position:sticky;top:0;z-index:100;box-shadow:0 2px 6px rgba(0,0,0,.2)}
.brand{color:#fff;text-decoration:none;font-size:20px;font-weight:700}
.logo-text{background:var(--accent);color:#fff;padding:2px 8px;border-radius:6px;margin-right:4px}
.nav-right{display:flex;align-items:center;gap:12px}
.badge-role{background:rgba(255,255,255,.2);padding:3px 10px;border-radius:20px;font-size:12px}
.nav-user{font-weight:600;max-width:160px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.btn-logout{background:rgba(255,255,255,.15);color:#fff;border:1px solid rgba(255,255,255,.3);
  padding:6px 14px;border-radius:6px;text-decoration:none;font-size:13px;transition:.2s}
.btn-logout:hover{background:rgba(255,255,255,.3)}

/* CONTAINER */
.container{max-width:1200px;margin:0 auto;padding:24px 16px}

/* CARDS */
.card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);
  border:1px solid var(--border);margin-bottom:20px}
.card-header{padding:16px 20px;border-bottom:1px solid var(--border);
  font-weight:700;font-size:16px;display:flex;align-items:center;justify-content:space-between}
.card-body{padding:20px}

/* GRID */
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:16px}
.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
@media(max-width:768px){.grid-2,.grid-3,.grid-4{grid-template-columns:1fr}}
@media(max-width:1024px){.grid-4{grid-template-columns:repeat(2,1fr)}}

/* STAT CARDS */
.stat-card{background:var(--card);border-radius:var(--radius);padding:20px;
  box-shadow:var(--shadow);border:1px solid var(--border);text-align:center}
.stat-card .stat-icon{font-size:32px;margin-bottom:8px}
.stat-card .stat-value{font-size:28px;font-weight:800;color:var(--primary)}
.stat-card .stat-label{color:var(--muted);font-size:13px;margin-top:4px}

/* FORMS */
.form-group{margin-bottom:16px}
.form-group label{display:block;font-weight:600;margin-bottom:6px;font-size:14px}
.form-control{width:100%;padding:9px 12px;border:1.5px solid var(--border);border-radius:7px;
  font-size:15px;transition:.2s;background:#fff}
.form-control:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px rgba(37,99,235,.12)}
.form-row{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px}

/* BUTTONS */
.btn{display:inline-flex;align-items:center;gap:6px;padding:9px 18px;border:none;
  border-radius:7px;font-size:14px;font-weight:600;cursor:pointer;text-decoration:none;transition:.2s}
.btn-primary{background:var(--primary);color:#fff}.btn-primary:hover{background:var(--primary-dark)}
.btn-success{background:var(--success);color:#fff}
.btn-danger{background:var(--danger);color:#fff}
.btn-warn{background:var(--warn);color:#fff}
.btn-ghost{background:transparent;border:1.5px solid var(--border);color:var(--text)}
.btn-sm{padding:5px 12px;font-size:13px}
.btn-block{width:100%;justify-content:center}

/* TABLES */
.table-wrap{overflow-x:auto;border-radius:var(--radius);border:1px solid var(--border)}
table{width:100%;border-collapse:collapse;font-size:14px}
th{background:#f1f5f9;padding:11px 14px;text-align:left;font-weight:700;
  color:var(--muted);font-size:13px;white-space:nowrap}
td{padding:10px 14px;border-top:1px solid var(--border);vertical-align:middle}
tr:hover td{background:#f8fafc}

/* BADGES */
.badge{display:inline-block;padding:3px 10px;border-radius:20px;font-size:12px;font-weight:600}
.badge-success{background:#dcfce7;color:var(--success)}
.badge-danger{background:#fee2e2;color:var(--danger)}
.badge-warn{background:#fef3c7;color:var(--warn)}
.badge-blue{background:#dbeafe;color:var(--primary)}
.badge-gray{background:#f1f5f9;color:var(--muted)}

/* TABS */
.tabs{display:flex;gap:4px;border-bottom:2px solid var(--border);margin-bottom:20px}
.tab{padding:10px 18px;cursor:pointer;border-radius:7px 7px 0 0;font-weight:600;
  color:var(--muted);transition:.2s;font-size:14px;background:none;border:none}
.tab.active{color:var(--primary);border-bottom:2px solid var(--primary);margin-bottom:-2px;background:#eff6ff}

/* MODAL */
.modal-overlay{display:none;position:fixed;inset:0;background:rgba(0,0,0,.5);z-index:200;
  align-items:center;justify-content:center}
.modal-overlay.open{display:flex}
.modal{background:#fff;border-radius:var(--radius);padding:28px;width:100%;max-width:520px;
  max-height:90vh;overflow-y:auto;box-shadow:0 20px 60px rgba(0,0,0,.2)}
.modal-title{font-size:18px;font-weight:800;margin-bottom:20px;color:var(--text)}
.modal-footer{display:flex;gap:10px;justify-content:flex-end;margin-top:20px}

/* ALERTS */
.alert{padding:12px 16px;border-radius:7px;margin-bottom:16px;font-size:14px}
.alert-success{background:#dcfce7;color:var(--success);border:1px solid #bbf7d0}
.alert-danger{background:#fee2e2;color:var(--danger);border:1px solid #fecaca}
.alert-info{background:#dbeafe;color:var(--primary);border:1px solid #bfdbfe}

/* SIDEBAR LAYOUT */
.page-layout{display:grid;grid-template-columns:240px 1fr;gap:20px;align-items:start}
.sidebar{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);
  border:1px solid var(--border);overflow:hidden;position:sticky;top:80px}
.sidebar-menu{list-style:none}
.sidebar-menu li a{display:flex;align-items:center;gap:10px;padding:12px 20px;
  color:var(--text);text-decoration:none;font-size:14px;transition:.15s}
.sidebar-menu li a:hover,.sidebar-menu li a.active{background:#eff6ff;color:var(--primary)}
.sidebar-menu li a .icon{width:20px;text-align:center}
.sidebar-sep{height:1px;background:var(--border);margin:8px 0}
@media(max-width:768px){.page-layout{grid-template-columns:1fr}.sidebar{position:static}}

/* PAYMENT */
.payment-item{display:flex;justify-content:space-between;align-items:center;
  padding:12px 0;border-bottom:1px solid var(--border)}
.payment-item:last-child{border:none}
.payment-amount{font-size:18px;font-weight:700}

/* SCHEDULE */
.schedule-grid{display:grid;grid-template-columns:repeat(7,1fr);gap:4px;font-size:13px}
.schedule-day{text-align:center;font-weight:700;padding:8px;background:#f1f5f9;border-radius:6px}
.schedule-slot{background:#eff6ff;border:1px solid #bfdbfe;border-radius:6px;padding:6px 8px;margin-bottom:4px}
.schedule-slot .subj{font-weight:700;color:var(--primary)}
.schedule-slot .time{color:var(--muted);font-size:11px}

/* CHART PLACEHOLDER */
.chart-bar-wrap{display:flex;flex-direction:column;gap:8px}
.chart-bar-row{display:flex;align-items:center;gap:8px;font-size:13px}
.chart-bar-label{width:110px;text-align:right;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chart-bar-track{flex:1;background:#f1f5f9;border-radius:4px;height:22px;position:relative}
.chart-bar-fill{height:100%;border-radius:4px;background:var(--primary);transition:.5s}
.chart-bar-val{position:absolute;right:8px;top:50%;transform:translateY(-50%);font-weight:700;font-size:12px;color:#fff}

/* LOGIN PAGE */
.login-page{min-height:100vh;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,#1d4ed8 0%,#2563eb 50%,#7c3aed 100%)}
.login-box{background:#fff;border-radius:16px;padding:40px;width:100%;max-width:400px;box-shadow:0 24px 60px rgba(0,0,0,.2)}
.login-logo{text-align:center;margin-bottom:28px}
.login-logo .logo-big{font-size:42px;font-weight:900;background:var(--primary);color:#fff;
  display:inline-block;padding:8px 18px;border-radius:12px}
.login-logo h2{margin-top:10px;font-size:22px;color:var(--text)}
.login-logo p{color:var(--muted);font-size:14px}