:root{
  --bg:#f4f6fb; --panel:#ffffff; --ink:#1c2433; --muted:#67718a;
  --line:#e3e8f2; --brand:#1f6feb; --brand-dk:#1551b8;
  --ok:#2f9e58; --okbg:#e6f6ec; --med:#e58b1a; --medbg:#fdf1e0;
  --high:#dc3434; --highbg:#fdeaea; --low:#caa400; --lowbg:#fbf6d8;
  --shadow:0 1px 3px rgba(20,30,60,.08),0 4px 16px rgba(20,30,60,.05);
}
*{box-sizing:border-box}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background:var(--bg);color:var(--ink);font-size:14.5px;line-height:1.55}
a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}
.container{max-width:1080px;margin:0 auto;padding:24px 20px}
.topbar{background:var(--panel);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.topbar .inner{max-width:1080px;margin:0 auto;display:flex;align-items:center;gap:18px;padding:12px 20px}
.brand{display:flex;align-items:center;gap:9px;font-weight:800;font-size:18px;color:var(--ink)}
.brand .logo{width:26px;height:26px;border-radius:7px;background:linear-gradient(135deg,var(--brand),#54a0ff);
  display:inline-flex;align-items:center;justify-content:center;color:#fff;font-weight:900}
.nav{display:flex;gap:4px;margin-left:8px;flex-wrap:wrap}
.nav a{padding:7px 12px;border-radius:8px;color:var(--muted);font-weight:600}
.nav a:hover{background:#eef3fc;text-decoration:none;color:var(--ink)}
.nav a.active{background:#e7f0ff;color:var(--brand-dk)}
.spacer{flex:1}
.userchip{display:flex;align-items:center;gap:9px;font-size:13px;color:var(--muted)}
.userchip .av{width:30px;height:30px;border-radius:50%;background:#dde6f7;color:var(--brand-dk);
  display:flex;align-items:center;justify-content:center;font-weight:800}
.badge{display:inline-block;padding:2px 9px;border-radius:999px;font-size:11px;font-weight:700;letter-spacing:.02em}
.badge.role-super{background:#efe2fb;color:#7a36c4}
.badge.role-instructor{background:#dceefb;color:#1769aa}
.badge.role-student{background:#e3f6e9;color:#27893f}
.card{background:var(--panel);border:1px solid var(--line);border-radius:14px;box-shadow:var(--shadow);padding:22px;margin-bottom:20px}
.card h2{margin:0 0 4px;font-size:17px}
.card .sub{color:var(--muted);margin:0 0 16px;font-size:13px}
.grid{display:grid;gap:16px}
.grid.cols-3{grid-template-columns:repeat(3,1fr)}
.grid.cols-2{grid-template-columns:repeat(2,1fr)}
@media(max-width:760px){.grid.cols-3,.grid.cols-2{grid-template-columns:1fr}.nav{display:none}}
.stat{background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:18px 20px;box-shadow:var(--shadow)}
.stat .n{font-size:30px;font-weight:800;line-height:1}
.stat .l{color:var(--muted);font-size:12.5px;margin-top:6px;text-transform:uppercase;letter-spacing:.05em}
table{width:100%;border-collapse:collapse;font-size:14px}
th{text-align:left;color:var(--muted);font-size:12px;text-transform:uppercase;letter-spacing:.04em;
  padding:10px 12px;border-bottom:2px solid var(--line)}
td{padding:12px;border-bottom:1px solid var(--line);vertical-align:middle}
tr:hover td{background:#fafbfe}
.btn{display:inline-flex;align-items:center;gap:7px;background:var(--brand);color:#fff;border:0;
  padding:9px 16px;border-radius:9px;font-weight:700;font-size:14px;cursor:pointer;transition:.15s}
.btn:hover{background:var(--brand-dk);text-decoration:none}
.btn.sm{padding:6px 11px;font-size:13px}
.btn.ghost{background:#eef3fc;color:var(--brand-dk)}
.btn.ghost:hover{background:#e0eafc}
.btn.danger{background:var(--high)}.btn.danger:hover{background:#b82626}
.btn.gray{background:#eceff5;color:var(--ink)}.btn.gray:hover{background:#e1e6ef}
label{display:block;font-weight:600;font-size:13px;margin:14px 0 5px}
input[type=text],input[type=email],input[type=password],input[type=date],input[type=datetime-local],
select,textarea{width:100%;padding:10px 12px;border:1px solid #d6deec;border-radius:9px;font-size:14px;
  font-family:inherit;background:#fff;transition:.15s}
input:focus,select:focus,textarea:focus{outline:0;border-color:var(--brand);box-shadow:0 0 0 3px rgba(31,111,235,.15)}
.help{color:var(--muted);font-size:12px;margin-top:4px}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:14px}
@media(max-width:600px){.row2{grid-template-columns:1fr}}
.flash{padding:12px 16px;border-radius:10px;margin-bottom:16px;font-weight:600;font-size:13.5px}
.flash.info{background:#e7f0ff;color:#1551b8}
.flash.success{background:var(--okbg);color:#1d7a3e}
.flash.error{background:var(--highbg);color:#b82626}
.flash.warning{background:var(--medbg);color:#a35c08}
.pill{display:inline-block;padding:3px 11px;border-radius:999px;font-weight:700;font-size:12.5px}
.sev-high{background:var(--highbg);color:var(--high)}
.sev-med{background:var(--medbg);color:var(--med)}
.sev-low{background:var(--lowbg);color:#9c7e00}
.sev-ok{background:var(--okbg);color:var(--ok)}
.status{display:inline-block;padding:3px 11px;border-radius:6px;font-size:12px;font-weight:700}
.status.done{background:var(--okbg);color:var(--ok)}
.status.processing{background:#eef0f5;color:#5a6478}
.status.error{background:var(--highbg);color:var(--high)}
.auth-wrap{min-height:100vh;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,#eef3fc,#dde8fb)}
.auth-card{background:#fff;border-radius:18px;box-shadow:0 12px 40px rgba(20,40,90,.16);
  width:100%;max-width:400px;padding:34px 30px;margin:16px}
.auth-card .brand{justify-content:center;font-size:22px;margin-bottom:6px}
.auth-card h1{text-align:center;font-size:19px;margin:6px 0 22px;color:var(--muted);font-weight:600}
.muted{color:var(--muted)}
.right{text-align:right}.center{text-align:center}
.bar{height:10px;border-radius:6px;background:#eef0f5;overflow:hidden}
.bar > span{display:block;height:100%}
.report-body{font-size:14.5px;line-height:1.85;background:#fff;border:1px solid var(--line);
  border-radius:12px;padding:24px}
.hl{background:#ffe0e0;border-bottom:2px solid #ff9a9a;border-radius:2px;padding:1px 2px}
.hl.med{background:#ffedcf;border-bottom-color:#f0b860}
.src-list{list-style:none;margin:0;padding:0}
.src-list li{display:flex;align-items:center;gap:12px;padding:9px 0;border-bottom:1px solid var(--line)}
.src-num{width:24px;height:24px;border-radius:50%;background:var(--brand);color:#fff;font-size:12px;font-weight:800;
  display:flex;align-items:center;justify-content:center;flex-shrink:0}
.src-type{font-size:11px;font-weight:700;padding:2px 8px;border-radius:999px;background:#eef3fc;color:#1769aa}
.donut{position:relative;width:130px;height:130px}
.donut .pct{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center}
.donut .pct b{font-size:30px;line-height:1}
.donut .pct span{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.04em}
.footer{text-align:center;color:var(--muted);font-size:12px;padding:24px}
.inline-form{display:inline}
.tag{font-size:11px;color:var(--muted)}
.empty{text-align:center;color:var(--muted);padding:40px 20px}
.empty .big{font-size:40px;margin-bottom:8px}