/* EduTrack v2 - Global Styles */
@import url('https://fonts.googleapis.com/css2?family=Syne:wght@600;700;800&family=Plus+Jakarta+Sans:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* ===== VARIABLES ===== */
:root {
    --bg:#08090f; --bg2:#0d0e1c; --card:#11121f; --card2:#161728;
    --border:#1c1d33; --border2:#222340;
    --accent:#6c5ce7; --accent-h:#5a4cd6; --accent2:#fd9644;
    --text:#e2e3f0; --text2:#8889aa; --muted:#50516a;
    --success:#00b894; --danger:#e17055; --warn:#fdcb6e; --info:#74b9ff;
    --sidebar-w:252px; --radius:14px;
    --shadow:0 8px 32px rgba(0,0,0,.45);
}
[data-theme="light"] {
    --bg:#f2f3fb; --bg2:#e8eaf6; --card:#fff; --card2:#f5f6ff;
    --border:#dde0f5; --border2:#c8cbec;
    --accent:#6c5ce7; --accent-h:#5a4cd6; --accent2:#e07b2a;
    --text:#1a1b2e; --text2:#4a4b6a; --muted:#888aaa;
    --success:#00b894; --danger:#d63031; --warn:#e17055; --info:#0984e3;
    --shadow:0 4px 20px rgba(108,92,231,.10);
}

/* ===== RESET ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
    font-family:'Plus Jakarta Sans',sans-serif;
    background:var(--bg);color:var(--text);
    min-height:100vh;font-size:14px;line-height:1.6;
    transition:background .3s,color .3s;
}

/* ===== LAYOUT ===== */
.layout{display:flex;min-height:100vh}

/* ===== SIDEBAR ===== */
.sidebar{
    width:var(--sidebar-w);background:var(--bg2);
    border-right:1px solid var(--border);
    display:flex;flex-direction:column;
    position:fixed;top:0;left:0;height:100vh;
    z-index:200;overflow-y:auto;overflow-x:hidden;
    transition:transform .3s ease,background .3s;
}
.sidebar-logo{
    padding:20px 18px 16px;border-bottom:1px solid var(--border);
    display:flex;align-items:center;gap:10px;flex-shrink:0;
}
.logo-icon{
    width:36px;height:36px;border-radius:10px;
    background:linear-gradient(135deg,var(--accent),var(--accent2));
    display:flex;align-items:center;justify-content:center;
    font-family:'Syne',sans-serif;font-weight:800;font-size:18px;color:#fff;
    flex-shrink:0;
}
.logo-text{
    font-family:'Syne',sans-serif;font-size:19px;font-weight:800;
    background:linear-gradient(135deg,var(--accent),var(--accent2));
    -webkit-background-clip:text;-webkit-text-fill-color:transparent;
}
.sidebar-nav{flex:1;padding:10px 8px;overflow-y:auto}
.nav-group-label{
    font-size:10px;font-weight:700;color:var(--muted);
    text-transform:uppercase;letter-spacing:1px;
    padding:10px 10px 4px;margin-top:4px;
}
.sidebar-nav a{
    display:flex;align-items:center;gap:10px;
    padding:9px 12px;border-radius:10px;
    color:var(--text2);text-decoration:none;
    font-size:13.5px;font-weight:500;
    transition:all .18s;margin-bottom:1px;position:relative;
}
.sidebar-nav a .ni{font-size:16px;flex-shrink:0;width:20px;text-align:center}
.sidebar-nav a .nb{
    margin-left:auto;background:var(--danger);color:#fff;
    font-size:10px;font-weight:700;padding:1px 6px;
    border-radius:20px;min-width:18px;text-align:center;
}
.sidebar-nav a:hover{background:var(--card);color:var(--text)}
.sidebar-nav a.active{
    background:rgba(108,92,231,.15);color:var(--accent);font-weight:600;
}
.sidebar-nav a.active::before{
    content:'';position:absolute;left:0;top:4px;bottom:4px;
    width:3px;background:var(--accent);border-radius:0 3px 3px 0;
}
.sidebar-footer{padding:12px 8px;border-top:1px solid var(--border);flex-shrink:0}
.user-box{
    display:flex;align-items:center;gap:10px;padding:10px;
    border-radius:10px;background:var(--card);margin-bottom:8px;
}
.uav{
    width:36px;height:36px;border-radius:50%;
    background:linear-gradient(135deg,var(--accent),var(--accent2));
    display:flex;align-items:center;justify-content:center;
    font-weight:700;font-size:14px;color:#fff;
    flex-shrink:0;overflow:hidden;
}
.uav img{width:100%;height:100%;object-fit:cover}
.uname{font-size:13px;font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.urole{
    font-size:10px;color:var(--accent);
    background:rgba(108,92,231,.12);
    padding:1px 7px;border-radius:20px;display:inline-block;margin-top:1px;
}
.sf-btns{display:flex;gap:6px}
.sf-btns a{
    flex:1;padding:7px;border-radius:8px;
    border:1px solid var(--border);background:transparent;
    color:var(--text2);text-decoration:none;font-size:12px;
    text-align:center;transition:all .18s;cursor:pointer;
    display:flex;align-items:center;justify-content:center;gap:4px;
}
.sf-btns a:hover{color:var(--danger);border-color:rgba(225,112,85,.4)}

/* Mobile */
.hamburger{
    display:none;position:fixed;top:12px;left:12px;z-index:300;
    background:var(--card);border:1px solid var(--border);
    border-radius:10px;width:40px;height:40px;
    align-items:center;justify-content:center;
    cursor:pointer;font-size:18px;color:var(--text);
    box-shadow:var(--shadow);
}
.sidebar-overlay{
    display:none;position:fixed;inset:0;
    background:rgba(0,0,0,.6);z-index:190;
}

/* ===== MAIN CONTENT ===== */
.main-content{
    margin-left:var(--sidebar-w);flex:1;
    min-height:100vh;padding:26px;
    background:var(--bg);transition:background .3s;
}
.topbar{
    display:flex;align-items:center;justify-content:space-between;
    margin-bottom:22px;gap:12px;flex-wrap:wrap;
}
.topbar-left{display:flex;align-items:center;gap:10px;flex-wrap:wrap}
.page-title{font-family:'Syne',sans-serif;font-size:21px;font-weight:800}

/* ===== CARDS ===== */
.card{
    background:var(--card);border:1px solid var(--border);
    border-radius:var(--radius);padding:20px;margin-bottom:16px;
    transition:background .3s,border-color .3s;
}
.card-title{
    font-family:'Syne',sans-serif;font-size:14px;font-weight:700;
    margin-bottom:14px;display:flex;align-items:center;gap:8px;
}
.card-title .ct-badge{
    background:rgba(108,92,231,.12);color:var(--accent);
    font-size:11px;padding:2px 8px;border-radius:20px;
}

/* Stats grid */
.stats-grid{
    display:grid;
    grid-template-columns:repeat(auto-fit,minmax(140px,1fr));
    gap:12px;margin-bottom:18px;
}
.stat-card{
    background:var(--card);border:1px solid var(--border);
    border-radius:var(--radius);padding:16px 18px;
    border-top:2px solid var(--border);
    transition:transform .2s,box-shadow .2s;
}
.stat-card:hover{transform:translateY(-2px);box-shadow:var(--shadow)}
.sc-accent{border-top-color:var(--accent)}
.sc-success{border-top-color:var(--success)}
.sc-warn{border-top-color:var(--warn)}
.sc-danger{border-top-color:var(--danger)}
.sc-info{border-top-color:var(--info)}
.stat-num{
    font-family:'Syne',sans-serif;font-size:28px;font-weight:800;
    line-height:1;margin-bottom:4px;
}
.stat-label{font-size:12px;color:var(--text2)}

/* ===== BUTTONS ===== */
.btn{
    padding:8px 16px;border-radius:9px;border:none;cursor:pointer;
    font-family:inherit;font-size:13px;font-weight:600;
    transition:all .18s;text-decoration:none;
    display:inline-flex;align-items:center;gap:6px;white-space:nowrap;
}
.btn:disabled{opacity:.5;cursor:not-allowed}
.btn-primary{background:var(--accent);color:#fff}
.btn-primary:hover{background:var(--accent-h);transform:translateY(-1px)}
.btn-success{background:rgba(0,184,148,.12);color:var(--success);border:1px solid rgba(0,184,148,.3)}
.btn-success:hover{background:rgba(0,184,148,.22)}
.btn-danger{background:rgba(225,112,85,.12);color:var(--danger);border:1px solid rgba(225,112,85,.3)}
.btn-danger:hover{background:rgba(225,112,85,.22)}
.btn-warn{background:rgba(253,203,110,.12);color:var(--warn);border:1px solid rgba(253,203,110,.3)}
.btn-warn:hover{background:rgba(253,203,110,.22)}
.btn-ghost{background:transparent;color:var(--text2);border:1px solid var(--border)}
.btn-ghost:hover{background:var(--card2);color:var(--text)}
.btn-sm{padding:5px 11px;font-size:12px}
.btn-lg{padding:12px 24px;font-size:14px}

/* ===== TABLE ===== */
.table-wrap{overflow-x:auto;border-radius:var(--radius)}
table{width:100%;border-collapse:collapse}
th{
    text-align:left;font-size:11px;font-weight:700;
    color:var(--muted);text-transform:uppercase;letter-spacing:.5px;
    padding:10px 14px;border-bottom:1px solid var(--border);white-space:nowrap;
}
td{
    padding:11px 14px;border-bottom:1px solid rgba(28,29,51,.4);
    font-size:13.5px;vertical-align:middle;
}
[data-theme="light"] td{border-bottom-color:rgba(200,203,236,.4)}
tr:last-child td{border-bottom:none}
tbody tr:hover td{background:rgba(108,92,231,.04)}

/* ===== BADGES ===== */
.badge{
    padding:3px 9px;border-radius:20px;
    font-size:11px;font-weight:700;display:inline-block;
}
.badge-admin{background:rgba(108,92,231,.15);color:var(--accent)}
.badge-mentor{background:rgba(253,150,68,.15);color:var(--accent2)}
.badge-student{background:rgba(0,184,148,.15);color:var(--success)}
.badge-active{background:rgba(0,184,148,.15);color:var(--success)}
.badge-inactive{background:rgba(80,81,106,.15);color:var(--muted)}
.badge-graded{background:rgba(0,184,148,.15);color:var(--success)}
.badge-submitted{background:rgba(253,203,110,.15);color:var(--warn)}
.badge-pending{background:rgba(80,81,106,.12);color:var(--muted)}

/* ===== ALERTS ===== */
.alert{
    padding:12px 16px;border-radius:10px;
    margin-bottom:14px;font-size:13.5px;
    display:flex;align-items:center;gap:8px;
}
.alert-success{background:rgba(0,184,148,.1);border:1px solid rgba(0,184,148,.3);color:var(--success)}
.alert-error{background:rgba(225,112,85,.1);border:1px solid rgba(225,112,85,.3);color:var(--danger)}
.alert-warn{background:rgba(253,203,110,.1);border:1px solid rgba(253,203,110,.3);color:var(--warn)}
.alert-info{background:rgba(116,185,255,.1);border:1px solid rgba(116,185,255,.3);color:var(--info)}

/* ===== FORMS ===== */
.form-group{margin-bottom:14px}
.form-group label{
    display:block;font-size:12.5px;font-weight:600;
    color:var(--text2);margin-bottom:5px;
}
.form-control{
    width:100%;background:var(--bg2);border:1px solid var(--border);
    border-radius:10px;padding:10px 14px;color:var(--text);
    font-family:inherit;font-size:14px;outline:none;
    transition:border-color .18s,box-shadow .18s;
}
.form-control:focus{
    border-color:var(--accent);
    box-shadow:0 0 0 3px rgba(108,92,231,.12);
}
.form-control::placeholder{color:var(--muted)}
.form-control option{background:var(--card)}
textarea.form-control{resize:vertical;min-height:80px}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.form-hint{font-size:11.5px;color:var(--muted);margin-top:4px}

/* ===== MODAL ===== */
.modal-overlay{
    display:none;position:fixed;inset:0;
    background:rgba(0,0,0,.65);backdrop-filter:blur(4px);
    z-index:500;align-items:center;justify-content:center;padding:16px;
}
.modal-overlay.open{display:flex}
.modal{
    background:var(--card);border:1px solid var(--border);
    border-radius:18px;padding:26px;width:100%;max-width:500px;
    position:relative;max-height:90vh;overflow-y:auto;
    box-shadow:0 24px 64px rgba(0,0,0,.5);
    animation:modalIn .22s ease;
}
.modal-lg{max-width:680px}
@keyframes modalIn{from{opacity:0;transform:scale(.95) translateY(8px)}to{opacity:1;transform:scale(1) translateY(0)}}
.modal-title{font-family:'Syne',sans-serif;font-size:17px;font-weight:800;margin-bottom:18px}
.modal-close{
    position:absolute;top:14px;right:14px;
    background:var(--card2);border:1px solid var(--border);
    border-radius:8px;width:28px;height:28px;
    display:flex;align-items:center;justify-content:center;
    cursor:pointer;color:var(--text2);font-size:15px;transition:all .18s;
}
.modal-close:hover{color:var(--danger);border-color:rgba(225,112,85,.4)}

/* ===== PROGRESS ===== */
.progress-bar{height:6px;background:var(--border);border-radius:3px;overflow:hidden}
.progress-fill{height:100%;background:linear-gradient(90deg,var(--accent),var(--accent2));border-radius:3px;transition:width .5s ease}

/* ===== TASK CARDS ===== */
.task-card{
    background:var(--card);border:1px solid var(--border);
    border-left:3px solid var(--border2);border-radius:var(--radius);
    padding:18px;margin-bottom:12px;transition:all .18s;
}
.task-card:hover{box-shadow:var(--shadow)}
.task-card.status-graded{border-left-color:var(--success)}
.task-card.status-submitted{border-left-color:var(--warn)}
.task-card.status-pending{border-left-color:var(--border2)}
.task-header{display:flex;align-items:flex-start;justify-content:space-between;gap:10px}
.task-title{font-weight:700;font-size:14.5px;margin-bottom:3px}
.task-meta{font-size:12px;color:var(--text2)}

/* ===== TABS ===== */
.tabs-bar{
    display:flex;gap:2px;background:var(--card2);
    border:1px solid var(--border);border-radius:12px;
    padding:4px;width:fit-content;margin-bottom:18px;flex-wrap:wrap;
}
.tab-btn{
    padding:7px 16px;border-radius:9px;cursor:pointer;
    font-size:13px;font-weight:500;color:var(--text2);
    border:none;background:none;font-family:inherit;transition:all .18s;
    text-decoration:none;display:inline-block;
}
.tab-btn.active{background:var(--card);color:var(--accent);font-weight:600;box-shadow:0 1px 4px rgba(0,0,0,.2)}

/* ===== RANKING ===== */
.rank-row{
    display:flex;align-items:center;gap:12px;
    padding:11px 0;border-bottom:1px solid var(--border);
}
.rank-row:last-child{border-bottom:none}
.rank-num{font-family:'Syne',sans-serif;font-weight:800;font-size:16px;width:26px;color:var(--muted);flex-shrink:0}
.rank-num.gold{color:#f9ca24}
.rank-num.silver{color:#b2bec3}
.rank-num.bronze{color:#cd7f32}

/* ===== EXAM ===== */
.exam-card{
    background:var(--card);border:1px solid var(--border);
    border-left:3px solid var(--border2);border-radius:var(--radius);
    padding:20px;margin-bottom:14px;transition:all .2s;
}
.exam-card:hover{box-shadow:var(--shadow)}
.exam-card.active-exam{border-left-color:var(--accent)}
.exam-card.done-exam{border-left-color:var(--success)}
.exam-timer{
    position:fixed;top:14px;right:14px;
    background:var(--card);border:2px solid var(--accent);
    border-radius:14px;padding:10px 18px;z-index:400;text-align:center;
    box-shadow:var(--shadow);min-width:100px;
}
.exam-timer .tm{font-family:'Syne',sans-serif;font-size:26px;font-weight:800;color:var(--accent)}
.exam-timer .tl{font-size:11px;color:var(--text2)}
.exam-timer.danger{border-color:var(--danger)}
.exam-timer.danger .tm{color:var(--danger)}
.exam-q-block{
    background:var(--card2);border:1px solid var(--border);
    border-radius:12px;padding:18px;margin-bottom:14px;
}
.math-display{
    background:var(--bg);border:1px solid var(--border);border-radius:10px;
    padding:10px 14px;font-family:'JetBrains Mono',monospace;font-size:17px;
    min-height:44px;color:var(--text);letter-spacing:.5px;margin-bottom:8px;
    cursor:text;
}
.math-kb{background:var(--card2);border:1px solid var(--border);border-radius:12px;padding:10px}
.math-kb-row{display:flex;gap:5px;margin-bottom:5px;flex-wrap:wrap}
.math-key{
    padding:7px 11px;border-radius:8px;
    background:var(--card);border:1px solid var(--border);
    color:var(--text);cursor:pointer;font-size:15px;
    font-family:'JetBrains Mono',monospace;transition:all .15s;
    min-width:36px;text-align:center;
}
.math-key:hover{background:var(--accent);color:#fff;border-color:var(--accent)}
.math-key.sp{background:rgba(108,92,231,.1);border-color:rgba(108,92,231,.3);color:var(--accent)}

/* ===== RESULT ===== */
.result-row{
    display:flex;align-items:flex-start;gap:10px;
    padding:10px 0;border-bottom:1px solid var(--border);font-size:13px;
}
.result-row:last-child{border-bottom:none}
.grade-big{font-family:'Syne',sans-serif;font-size:30px;font-weight:800;color:var(--success)}
.comment-block{
    background:var(--bg2);border-left:3px solid var(--accent);
    border-radius:0 10px 10px 0;padding:12px 14px;
    font-size:13px;line-height:1.7;color:var(--text2);margin-top:8px;
}

/* ===== HELP ===== */
.help-section{margin-bottom:18px}
.help-section h4{font-size:13.5px;font-weight:700;color:var(--accent);margin-bottom:8px;display:flex;align-items:center;gap:6px}
.help-item{display:flex;gap:10px;padding:7px 0;border-bottom:1px solid var(--border);font-size:13px;color:var(--text2)}
.help-item:last-child{border-bottom:none}
.help-item strong{color:var(--text);flex-shrink:0;min-width:120px}
.tg-btn{
    display:flex;align-items:center;justify-content:center;gap:10px;
    width:100%;padding:13px;
    background:linear-gradient(135deg,#229ed9,#1a7dbb);color:#fff;
    border-radius:12px;text-decoration:none;font-weight:700;font-size:14px;
    margin-top:10px;transition:opacity .2s;
}
.tg-btn:hover{opacity:.9}

/* ===== NOT-SUBMITTED BOX ===== */
.ns-box{
    background:var(--bg2);border:1px solid var(--border);
    border-radius:10px;padding:12px;font-size:13px;
    line-height:2;color:var(--text2);
}
.copy-btn{
    padding:5px 12px;border-radius:8px;border:1px solid var(--border);
    background:transparent;color:var(--text2);font-size:12px;
    cursor:pointer;transition:all .18s;font-family:inherit;margin-top:8px;
}
.copy-btn:hover{color:var(--text);border-color:var(--accent)}

/* ===== MENTOR CARD ===== */
.mentor-row{
    display:flex;align-items:center;gap:12px;
    padding:14px;background:var(--card2);
    border-radius:12px;margin-bottom:10px;
}
.m-ava{
    width:42px;height:42px;border-radius:50%;
    background:linear-gradient(135deg,var(--accent),var(--accent2));
    display:flex;align-items:center;justify-content:center;
    font-weight:700;font-size:17px;color:#fff;
    flex-shrink:0;overflow:hidden;
}
.m-ava img{width:100%;height:100%;object-fit:cover}

/* ===== AVATAR ===== */
.avatar{
    width:36px;height:36px;border-radius:50%;
    background:linear-gradient(135deg,var(--accent),var(--accent2));
    display:flex;align-items:center;justify-content:center;
    font-weight:700;font-size:14px;color:#fff;
    flex-shrink:0;overflow:hidden;
}
.avatar img{width:100%;height:100%;object-fit:cover}
.avatar-lg{width:72px;height:72px;font-size:28px;margin-bottom:14px}

/* ===== FILE VIEWER ===== */
.file-viewer{border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;background:var(--bg)}
.file-viewer iframe,.file-viewer img{width:100%;display:block;border:none}

/* ===== RESPONSIVE ===== */
@media(max-width:900px){
    .sidebar{transform:translateX(-100%)}
    .sidebar.open{transform:translateX(0);box-shadow:4px 0 30px rgba(0,0,0,.5)}
    .sidebar-overlay.open{display:block}
    .hamburger{display:flex}
    .main-content{margin-left:0;padding:58px 14px 28px}
    .stats-grid{grid-template-columns:repeat(2,1fr)}
    .form-row{grid-template-columns:1fr}
    .page-title{font-size:18px}
    .modal{padding:18px}
    .exam-timer{top:auto;bottom:14px;right:14px;left:14px;text-align:center}
    .tabs-bar{width:100%}
}
@media(max-width:480px){
    .stats-grid{grid-template-columns:1fr 1fr}
    th,td{padding:8px 10px}
    table{font-size:12px}
    .btn-sm{padding:4px 9px;font-size:11px}
}