:root{--bg:#0b0d10;--bg2:#0e1115;--bg3:#0e1216;--border:#14161b;--text:#f7f9fb;--muted:#97a0b2;--accent:#8b5cf6;--ah:#7c3aed;--green:#3fb950;--red:#d4882a;--yellow:#d29922;--blue:#58a6ff;--r:8px;--sidebar:220px;}
*{box-sizing:border-box;margin:0;padding:0;}
body{background:var(--bg);color:var(--text);font-family:'Inter','Segoe UI',system-ui,sans-serif;display:flex;min-height:100vh;}
.sidebar{width:var(--sidebar);background:var(--bg2);border-right:1px solid var(--border);display:flex;flex-direction:column;position:fixed;top:0;left:0;height:100vh;z-index:100;}
.sidebar-logo{padding:18px 16px;border-bottom:1px solid var(--border);display:flex;align-items:center;gap:10px;}
.sidebar-logo .icon{font-size:26px;}
.sidebar-logo .name{font-weight:700;font-size:15px;color:var(--pril);}
.sidebar-logo .badge{font-size:10px;background:#06b6d4;color:#fff;padding:2px 6px;border-radius:10px;margin-left:auto;}
nav{flex:1;overflow-y:auto;padding:8px 0;}
.nav-item{display:flex;align-items:center;gap:10px;padding:9px 16px;cursor:pointer;color:var(--muted);font-size:13px;border-left:3px solid transparent;transition:all 0.15s;}
.nav-item:hover{background:var(--bg3);color:var(--text);}
.nav-item.active{background:rgba(124,58,237,0.15);color:var(--accent);border-left-color:var(--accent);}
.nav-item .icon{font-size:16px;width:20px;text-align:center;}
.sidebar nav{flex:1;overflow-y:auto;}.sidebar-footer{padding:12px 16px;border-top:1px solid var(--border);margin-top:auto;}
.user-chip{display:flex;align-items:center;gap:10px;}
.user-chip .avatar{font-size:22px;}
.user-chip .info .name{font-size:13px;font-weight:600;}
.user-chip .info .role{font-size:11px;color:var(--muted);}
.logout-btn{margin-left:auto;background:none;border:none;cursor:pointer;color:var(--muted);font-size:18px;padding:4px;}
.logout-btn:hover{color:var(--red);}
.main{margin-left:var(--sidebar);flex:1;display:flex;flex-direction:column;}
.topbar{background:var(--bg2);border-bottom:1px solid var(--border);padding:14px 24px;display:flex;align-items:center;position:sticky;top:0;z-index:50;}
.topbar h1{font-size:18px;font-weight:600;flex:1;}
.page{display:none;padding:24px;flex:1;}
.page.active{display:block;}
.stats-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:14px;margin-bottom:24px;}
.stat-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--r);padding:16px;position:relative;}
.stat-card::before{content:'';position:absolute;top:0;left:0;right:0;height:3px;background:var(--accent);border-radius:var(--r) var(--r) 0 0;}
.stat-card.green::before{background:var(--green);}
.stat-card.blue::before{background:var(--blue);}
.stat-card.yellow::before{background:var(--yellow);}
.stat-card .label{font-size:11px;color:var(--muted);text-transform:uppercase;margin-bottom:6px;}
.stat-card .value{font-size:26px;font-weight:700;}
.student-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px;}
.student-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--r);padding:18px;cursor:pointer;transition:border-color 0.2s;}
.student-card:hover{border-color:var(--accent);}
.student-card .sc-top{display:flex;align-items:center;gap:12px;margin-bottom:12px;}
.student-card .sc-avatar{font-size:32px;}
.student-card .sc-name{font-weight:600;font-size:14px;}
.student-card .sc-email{font-size:11px;color:var(--muted);}
.sc-stats{display:flex;gap:16px;margin-bottom:12px;}
.sc-stat{text-align:center;}
.sc-stat .sv{font-size:18px;font-weight:700;}
.sc-stat .sl{font-size:10px;color:var(--muted);}
.progress-bar{height:6px;background:var(--bg3);border-radius:3px;overflow:hidden;margin-bottom:8px;}
.progress-bar-fill{height:100%;background:var(--accent);border-radius:3px;}
.sc-last{font-size:11px;color:var(--muted);}
.badge{display:inline-block;padding:2px 8px;border-radius:12px;font-size:11px;font-weight:600;}
.badge-active{background:rgba(63,185,80,0.2);color:var(--green);}
.badge-pending{background:rgba(88,166,255,0.2);color:var(--blue);}
.badge-suspended{background:rgba(210,153,34,0.2);color:var(--yellow);}
.table-card{background:var(--bg2);border:1px solid var(--border);border-radius:var(--r);overflow:hidden;margin-bottom:20px;}
.table-header{padding:14px 18px;display:flex;align-items:center;gap:12px;border-bottom:1px solid var(--border);}
.table-header h3{font-size:15px;font-weight:600;flex:1;}
.search-input{background:var(--bg3);border:1px solid var(--border);border-radius:6px;padding:7px 12px;color:var(--text);font-size:13px;outline:none;}
.search-input:focus{border-color:var(--accent);}
.btn-sm{padding:6px 12px;border-radius:6px;font-size:12px;font-weight:600;cursor:pointer;border:none;transition:background 0.2s;}
.btn-primary{background:var(--accent);color:#fff;}
.btn-primary:hover{background:var(--ah);}
.btn-danger{background:var(--red);color:#fff;}
.btn-ghost{background:var(--bg3);color:var(--text);border:1px solid var(--border);}
.btn-ghost:hover{background:var(--border);}
table{width:100%;border-collapse:collapse;}
th{padding:10px 14px;text-align:left;font-size:11px;color:var(--muted);text-transform:uppercase;border-bottom:1px solid var(--border);}
td{padding:10px 14px;font-size:13px;border-bottom:1px solid rgba(48,54,61,0.5);}
tr:last-child td{border-bottom:none;}
tr:hover td{background:rgba(48,54,61,0.3);}
.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,0.6);z-index:200;display:none;align-items:flex-start;justify-content:flex-end;}
.modal-overlay.open{display:flex;}
.drawer{background:var(--bg2);border-left:1px solid var(--border);width:100%;max-width:560px;height:100vh;overflow-y:auto;padding:24px;animation:slideIn 0.3s ease;}
@keyframes slideIn{from{transform:translateX(100%)}to{transform:translateX(0)}}
.drawer-header{display:flex;align-items:center;gap:12px;margin-bottom:20px;}
.drawer-header h2{font-size:18px;font-weight:600;flex:1;}
.close-btn{background:none;border:none;cursor:pointer;color:var(--muted);font-size:20px;padding:4px;}
.close-btn:hover{color:var(--text);}
.tab-bar{display:flex;gap:2px;background:var(--bg3);border-radius:8px;padding:4px;margin-bottom:20px;}
.tab{flex:1;padding:7px;text-align:center;border-radius:6px;cursor:pointer;font-size:13px;color:var(--muted);transition:all 0.2s;}
.tab.active{background:var(--bg2);color:var(--text);}
.tab-content{display:none;}
.tab-content.active{display:block;}
.form-group{margin-bottom:14px;}
.form-group label{display:block;font-size:12px;color:var(--muted);margin-bottom:5px;}
.form-group input,.form-group select,.form-group textarea{width:100%;background:var(--bg3);border:1px solid var(--border);border-radius:6px;padding:9px 12px;color:var(--text);font-size:13px;outline:none;}
.form-group input:focus,.form-group select:focus{border-color:var(--accent);}
.toast{position:fixed;bottom:24px;right:24px;background:var(--bg2);border:1px solid var(--border);border-radius:var(--r);padding:12px 18px;font-size:13px;z-index:999;transform:translateY(100px);opacity:0;transition:all 0.3s;max-width:300px;}
.toast.show{transform:translateY(0);opacity:1;}
.toast.success{border-left:4px solid var(--green);}
.toast.error{border-left:4px solid var(--red);}
.grade-row{display:flex;gap:10px;align-items:flex-end;margin-bottom:12px;}
.grade-row .form-group{flex:1;margin:0;}
.loading{text-align:center;padding:32px;color:var(--muted);}

/* ── Extracted from inline styles ─────────────────────────────────────────── */
.nav-badge-pill{margin-left:auto;background:var(--red);color:#fff;font-size:10px;padding:1px 6px;border-radius:10px;}
.courses-tab-on{background:var(--accent);color:#fff;border-color:var(--accent);}
.modal-dialog{background:var(--bg2);border:1px solid var(--border);border-radius:12px;padding:24px;width:100%;margin:auto;}
.modal-sm{max-width:400px;}
.modal-md{max-width:460px;}
.modal-lg{max-width:500px;}
.modal-footer{display:flex;gap:10px;justify-content:flex-end;margin-top:16px;}
.modal-section-divider{border-top:1px solid var(--border);padding-top:14px;}
.form-control{width:100%;padding:8px;background:var(--bg3);border:1px solid var(--border);border-radius:6px;color:var(--text);font-size:13px;}
.country-code-select{width:130px;flex-shrink:0;border-radius:8px;}
.textarea-md{resize:vertical;min-height:80px;}
.textarea-sm{resize:vertical;min-height:60px;}
.creds-box{background:var(--bg3);border:1px solid var(--border);border-radius:8px;padding:16px;text-align:left;margin-bottom:16px;}
.creds-label{font-size:12px;color:var(--muted);display:block;}
.creds-email-val{font-size:14px;word-break:break-all;}
.creds-pass-val{font-size:16px;letter-spacing:2px;}
.assign-student-list{max-height:240px;overflow-y:auto;border:1px solid var(--border);border-radius:8px;padding:8px;display:flex;flex-direction:column;gap:6px;}
.preview-list{max-height:220px;overflow-y:auto;border:1px solid var(--border);border-radius:8px;padding:8px;font-size:13px;}
.progress-track{background:var(--bg3);border-radius:8px;height:10px;overflow:hidden;}
.progress-track .progress-fill{height:100%;background:var(--accent);border-radius:8px;transition:width 0.4s;}
.qr-video{width:100%;border-radius:8px;background:#000;}
.inv-tab-bar{display:flex;gap:0;border:1px solid var(--border);border-radius:8px;overflow:hidden;margin-bottom:18px;}
.inv-tab{flex:1;padding:8px;background:var(--bg3);color:var(--muted);border:none;cursor:pointer;font-size:.85rem;}
.inv-tab.active{background:var(--accent);color:#fff;}
.msg-layout{display:flex;gap:16px;height:520px;}
.msg-thread-list{width:280px;flex-shrink:0;background:var(--bg2);border:1px solid var(--border);border-radius:var(--r);overflow-y:auto;}
.msg-thread-header{padding:12px 14px;border-bottom:1px solid var(--border);font-size:13px;font-weight:600;}
.msg-convo-panel{flex:1;background:var(--bg2);border:1px solid var(--border);border-radius:var(--r);display:flex;flex-direction:column;}
.msg-convo-header{padding:12px 16px;border-bottom:1px solid var(--border);font-size:13px;font-weight:600;}
.msg-chat-area{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:10px;}
.msg-reply-area{padding:12px 16px;border-top:1px solid var(--border);gap:8px;align-items:flex-end;}
.msg-reply-input{flex:1;background:var(--bg3);border:1px solid var(--border);border-radius:6px;padding:9px 12px;color:var(--text);font-size:13px;outline:none;resize:none;min-height:60px;width:100%;margin-right:8px;}
.msg-send-btn{height:36px;}
.mb-0{margin-bottom:0;}
.flex-col{flex-direction:column;}