:root{--brand:#0B3B8C;--ink:#111827;--ink2:#4b5563;--muted:#6b7280;--line:#e5e7eb;--bg:#f4f6fa;--card:#fff;--green:#059669;--red:#dc2626;--amber:#d97706;--radius:12px}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{font:15px/1.55 system-ui,-apple-system,"Segoe UI",Roboto,"Noto Sans Sinhala",Arial,sans-serif;color:var(--ink);background:var(--bg)}
a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}
h1,h2,h3,h4{line-height:1.25;margin:0 0 .6em}h2{font-size:1.25rem}h3{font-size:1.05rem}
img{max-width:100%}
.muted{color:var(--muted)}.small{font-size:.85rem}.right{text-align:right}.nowrap{white-space:nowrap}
/* app shell */
.app{display:flex;min-height:100vh}
.sidebar{width:248px;background:#0f172a;color:#cbd5e1;flex-shrink:0;position:sticky;top:0;height:100vh;overflow-y:auto;padding:14px 10px}
.sidebar .brand{display:flex;align-items:center;gap:10px;color:#fff;font-weight:700;padding:8px 10px 18px;font-size:1rem}
.sidebar .brand img{max-height:40px}
.logo-mark{background:var(--brand);color:#fff;border-radius:8px;padding:6px 8px;font-size:.8rem;letter-spacing:.5px}
.sidebar nav a{display:flex;align-items:center;gap:10px;color:#cbd5e1;padding:9px 12px;border-radius:8px;margin:2px 0}
.sidebar nav a:hover{background:#1e293b;text-decoration:none;color:#fff}
.sidebar nav a.active{background:var(--brand);color:#fff}
.sidebar .ic{width:20px;text-align:center;opacity:.85}
.nav-sep{font-size:.7rem;text-transform:uppercase;letter-spacing:1px;color:#64748b;padding:16px 12px 4px}
.main{flex:1;min-width:0;display:flex;flex-direction:column}
.topbar{display:flex;align-items:center;gap:14px;background:#fff;border-bottom:1px solid var(--line);padding:12px 24px;position:sticky;top:0;z-index:5}
.topbar h1{font-size:1.15rem;margin:0;flex:1}
.who{display:flex;align-items:center;gap:10px;font-size:.9rem}
.burger{display:none;border:0;background:none;font-size:22px;cursor:pointer}
.content{padding:24px;max-width:1240px;width:100%}
@media(max-width:860px){.sidebar{position:fixed;left:-260px;z-index:20;transition:left .2s}.sidebar.open{left:0}.burger{display:block}.content{padding:16px}.who span{display:none}}
/* components */
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:20px;margin-bottom:18px}
.card-h{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:14px;flex-wrap:wrap}.card-h h2,.card-h h3{margin:0}
.grid{display:grid;gap:18px}.g2{grid-template-columns:repeat(auto-fit,minmax(320px,1fr))}.g3{grid-template-columns:repeat(auto-fill,minmax(270px,1fr))}.g4{grid-template-columns:repeat(auto-fit,minmax(180px,1fr))}
.stat{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:16px 18px}
.stat b{display:block;font-size:1.7rem;line-height:1.1}.stat span{color:var(--muted);font-size:.85rem}
.course-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;display:flex;flex-direction:column;color:inherit}
.course-card:hover{box-shadow:0 6px 18px rgba(15,23,42,.08);text-decoration:none}
.course-card .cover{height:120px;background:linear-gradient(135deg,var(--brand),#1e293b);background-size:cover;background-position:center;color:#fff;display:flex;align-items:flex-end;padding:12px;font-weight:600}
.course-card .body{padding:14px 16px;flex:1;display:flex;flex-direction:column;gap:8px}
.progress{height:8px;background:#e5e7eb;border-radius:9px;overflow:hidden}.progress span{display:block;height:100%;background:var(--green)}
.btn{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--brand);background:var(--brand);color:#fff;padding:9px 16px;border-radius:9px;font:inherit;font-weight:600;cursor:pointer;text-decoration:none!important;line-height:1.2}
.btn:hover{filter:brightness(1.08)}
.btn-ghost{background:#fff;color:var(--ink);border-color:var(--line)}
.btn-danger{background:var(--red);border-color:var(--red)}
.btn-green{background:var(--green);border-color:var(--green)}
.btn-sm{padding:5px 10px;font-size:.85rem;border-radius:7px}
.btn-block{width:100%;justify-content:center}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.actions{display:flex;gap:8px;flex-wrap:wrap;align-items:center}
.badge{display:inline-block;padding:2px 9px;border-radius:99px;font-size:.75rem;font-weight:600;background:#eef2ff;color:var(--brand)}
.badge-green{background:#d1fae5;color:#065f46}.badge-red{background:#fee2e2;color:#991b1b}.badge-amber{background:#fef3c7;color:#92400e}.badge-grey{background:#f3f4f6;color:#374151}
.alert{padding:12px 16px;border-radius:10px;margin-bottom:16px;border:1px solid}
.alert-success{background:#ecfdf5;border-color:#a7f3d0;color:#065f46}.alert-error{background:#fef2f2;border-color:#fecaca;color:#991b1b}.alert-info{background:#eff6ff;border-color:#bfdbfe;color:#1e40af}.alert-warning{background:#fffbeb;border-color:#fde68a;color:#92400e}
.empty{padding:28px;text-align:center;color:var(--muted);border:1px dashed var(--line);border-radius:var(--radius);background:#fff}
/* tables */
.table-wrap{overflow-x:auto}
table.t{width:100%;border-collapse:collapse;font-size:.92rem}
table.t th,table.t td{padding:10px 12px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}
table.t th{background:#f9fafb;font-weight:600;color:var(--ink2);font-size:.8rem;text-transform:uppercase;letter-spacing:.4px}
table.t tr:hover td{background:#fafbff}
/* forms */
label{display:block;font-weight:600;font-size:.88rem;margin:0 0 5px}
.field{margin-bottom:14px}
input[type=text],input[type=email],input[type=password],input[type=number],input[type=url],input[type=tel],input[type=datetime-local],input[type=date],input[type=color],select,textarea{width:100%;padding:10px 12px;border:1px solid #d1d5db;border-radius:9px;font:inherit;background:#fff;color:var(--ink)}
input[type=color]{height:42px;padding:4px}
textarea{min-height:110px;resize:vertical}
input:focus,select:focus,textarea:focus{outline:2px solid color-mix(in srgb,var(--brand) 35%,transparent);border-color:var(--brand)}
.hint{font-size:.8rem;color:var(--muted);margin-top:4px}
.row{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:14px}
.check{display:flex;align-items:center;gap:8px;font-weight:500}
.check input{width:auto}
.filters{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:14px}.filters>*{width:auto;min-width:160px}
.pager{display:flex;gap:4px;margin-top:14px;flex-wrap:wrap}.pager a,.pager b,.pager span{padding:5px 10px;border-radius:6px;border:1px solid var(--line);background:#fff}.pager b{background:var(--brand);color:#fff;border-color:var(--brand)}
/* public / login */
.public{min-height:100vh;display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#0f172a, var(--brand));padding:20px}
.auth{background:#fff;border-radius:16px;padding:32px;width:100%;max-width:420px;box-shadow:0 20px 50px rgba(0,0,0,.25)}
.auth .brand{display:flex;align-items:center;gap:10px;font-weight:700;margin-bottom:20px;font-size:1.05rem}
.auth .brand img{max-height:48px}
.otp-input{font-size:28px!important;letter-spacing:12px;text-align:center;font-weight:700}
/* course outline / lesson */
.outline .module{border:1px solid var(--line);border-radius:10px;margin-bottom:12px;background:#fff;overflow:hidden}
.outline .module h3{margin:0;padding:12px 16px;background:#f9fafb;border-bottom:1px solid var(--line);font-size:.98rem;display:flex;justify-content:space-between}
.outline .lesson{display:flex;align-items:center;gap:10px;padding:10px 16px;border-bottom:1px solid #f1f5f9;color:inherit}
.outline .lesson:last-child{border-bottom:0}
.outline .lesson:hover{background:#fafbff;text-decoration:none}
.outline .lesson .t{width:22px;text-align:center}
.outline .lesson.done .t{color:var(--green);font-weight:700}
.outline .lesson.current{background:#eef2ff}
.lesson-layout{display:grid;grid-template-columns:1fr 320px;gap:18px}
@media(max-width:1000px){.lesson-layout{grid-template-columns:1fr}}
.video{position:relative;padding-top:56.25%;background:#000;border-radius:10px;overflow:hidden}
.video iframe,.video video{position:absolute;inset:0;width:100%;height:100%;border:0}
.pdf-frame{width:100%;height:78vh;border:1px solid var(--line);border-radius:10px}
.prose{max-width:780px}.prose img{border-radius:8px}.prose table{border-collapse:collapse}.prose td,.prose th{border:1px solid var(--line);padding:6px 10px}
/* quiz */
.q{border:1px solid var(--line);border-radius:10px;padding:16px;margin-bottom:12px;background:#fff}
.q .opt{display:flex;gap:10px;align-items:flex-start;padding:8px 10px;border-radius:8px;cursor:pointer;font-weight:400;margin:4px 0;border:1px solid transparent}
.q .opt:hover{background:#f9fafb}
.q .opt input{margin-top:4px;width:auto}
.q .opt.correct{background:#ecfdf5;border-color:#a7f3d0}.q .opt.wrong{background:#fef2f2;border-color:#fecaca}
.timer{position:sticky;top:64px;z-index:4;background:#111827;color:#fff;border-radius:10px;padding:8px 14px;display:inline-block;font-weight:700;margin-bottom:12px}
.timer.low{background:var(--red)}
/* certificate */
.cert{background:#fff;border:12px double var(--brand);padding:56px 40px;text-align:center;max-width:900px;margin:20px auto}
.cert h1{font-family:Georgia,serif;font-size:2.4rem;color:var(--brand)}
.cert .name{font-family:Georgia,serif;font-size:2rem;border-bottom:1px solid #999;display:inline-block;padding:0 30px 6px;margin:14px 0}
@media print{.sidebar,.topbar,.no-print{display:none!important}.content{padding:0}.app{display:block}body{background:#fff}}
code{background:#f3f4f6;padding:1px 5px;border-radius:4px;font-size:.88em}
pre.code{background:#0f172a;color:#e2e8f0;padding:14px;border-radius:10px;overflow:auto;font-size:.82rem}
.tabs{display:flex;gap:4px;border-bottom:1px solid var(--line);margin-bottom:16px;flex-wrap:wrap}
.tabs a{padding:9px 14px;border-bottom:2px solid transparent;color:var(--ink2)}.tabs a.active{border-color:var(--brand);color:var(--brand);font-weight:600}.tabs a:hover{text-decoration:none}