/* ============================================================
   QuizHive – Admin Stylesheet
   ============================================================ */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

:root {
  --primary:      #6366f1;
  --primary-dark: #4f46e5;
  --primary-light:#818cf8;
  --secondary:    #06b6d4;
  --success:      #10b981;
  --warning:      #f59e0b;
  --danger:       #ef4444;
  --dark:         #0f172a;
  --dark-2:       #1e293b;
  --dark-3:       #334155;
  --sidebar-bg:   #0d1117;
  --sidebar-w:    268px;
  --gray:         #64748b;
  --gray-light:   #94a3b8;
  --border:       #e2e8f0;
  --bg:           #f8fafc;
  --white:        #ffffff;
  --topbar-h:     68px;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.08),0 1px 2px rgba(0,0,0,.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,.08),0 2px 4px rgba(0,0,0,.04);
  --shadow-lg: 0 20px 40px rgba(0,0,0,.10);
  --shadow-xl: 0 32px 64px rgba(0,0,0,.14);
  --shadow-glow: 0 0 0 1px rgba(99,102,241,.08), 0 18px 40px rgba(99,102,241,.16);

  --radius-sm: 8px; --radius: 14px; --radius-lg: 22px;
  --transition: all .22s cubic-bezier(.4,0,.2,1);
}

*,*::before,*::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; }
body {
  font-family:'Inter',system-ui,sans-serif;
  background:var(--bg); color:var(--dark);
  display:flex; min-height:100vh;
  -webkit-font-smoothing:antialiased;
}

::-webkit-scrollbar { width:5px; height:5px; }
::-webkit-scrollbar-track { background:var(--bg); }
::-webkit-scrollbar-thumb { background:var(--gray-light); border-radius:3px; }

/* ── Sidebar ─────────────────────────────────────────────────── */
.sidebar {
  width:var(--sidebar-w); background:var(--sidebar-bg);
  position:fixed; top:0; left:0; height:100vh;
  display:flex; flex-direction:column;
  z-index:200; overflow-y:auto;
  transition:var(--transition);
  box-shadow:4px 0 24px rgba(0,0,0,.25);
}

.sidebar-brand {
  display:flex; align-items:center; gap:10px;
  padding:1.4rem 1.3rem; border-bottom:1px solid rgba(255,255,255,.05);
  text-decoration:none; flex-shrink:0;
}
.brand-icon {
  width:40px; height:40px;
  background:linear-gradient(135deg,var(--primary),#7c3aed);
  border-radius:10px; display:flex; align-items:center; justify-content:center;
  font-size:1.2rem; flex-shrink:0;
  box-shadow:0 4px 14px rgba(99,102,241,.4);
}
.sidebar-brand-title {
  font-weight:800; font-size:.95rem; line-height:1.2;
  background:linear-gradient(135deg,#fff,#a5b4fc);
  -webkit-background-clip:text; -webkit-text-fill-color:transparent; background-clip:text;
}
.sidebar-brand-sub   { color:rgba(255,255,255,.35); font-size:.65rem; letter-spacing:.1em; text-transform:uppercase; margin-top:.1rem; }

.sidebar-admin-info {
  padding:1rem 1.3rem; border-bottom:1px solid rgba(255,255,255,.05);
  display:flex; align-items:center; gap:.75rem; flex-shrink:0;
}
.admin-avatar-sm {
  width:38px; height:38px;
  background:linear-gradient(135deg,var(--primary),var(--secondary));
  border-radius:50%; display:flex; align-items:center; justify-content:center;
  font-weight:700; font-size:.88rem; color:white; flex-shrink:0;
}
.admin-info-name { color:white; font-size:.85rem; font-weight:600; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }
.admin-info-role { color:rgba(255,255,255,.35); font-size:.66rem; text-transform:uppercase; letter-spacing:.08em; }

.sidebar-nav { flex:1; padding:.75rem 0; }
.sidebar-nav-section { padding:.8rem 1.3rem .3rem; }
.sidebar-nav-section-title { color:rgba(255,255,255,.22); font-size:.62rem; font-weight:700; letter-spacing:.16em; text-transform:uppercase; }

.sidebar-nav a {
  display:flex; align-items:center; gap:.75rem;
  padding:.65rem 1.3rem; text-decoration:none;
  color:rgba(255,255,255,.5); font-size:.855rem; font-weight:500;
  border-left:3px solid transparent; transition:var(--transition); margin:.05rem 0;
  position:relative;
}
.sidebar-nav a:hover { color:rgba(255,255,255,.9); background:rgba(255,255,255,.04); }
.sidebar-nav a.active {
  color:white; background:rgba(99,102,241,.18);
  border-left-color:var(--primary); font-weight:600;
}
.sidebar-nav a .nav-icon { width:20px; text-align:center; font-size:.95rem; flex-shrink:0; }
.sidebar-nav a .nav-badge {
  margin-left:auto; background:var(--primary); color:white;
  padding:.1rem .45rem; border-radius:50px; font-size:.62rem; font-weight:700;
}

.sidebar-footer { padding:1rem 1.3rem; border-top:1px solid rgba(255,255,255,.05); flex-shrink:0; }
.sidebar-footer a {
  display:flex; align-items:center; gap:.75rem;
  color:rgba(255,255,255,.35); text-decoration:none;
  font-size:.84rem; font-weight:500; padding:.55rem .8rem;
  border-radius:var(--radius-sm); transition:var(--transition);
}
.sidebar-footer a:hover { color:var(--danger); background:rgba(239,68,68,.1); }

/* ── Main area ──────────────────────────────────────────────── */
.admin-main { margin-left:var(--sidebar-w); flex:1; display:flex; flex-direction:column; min-height:100vh; }

/* ── Topbar ─────────────────────────────────────────────────── */
.admin-topbar {
  background:var(--white); border-bottom:1px solid var(--border);
  padding:0 2rem; height:var(--topbar-h);
  display:flex; align-items:center; justify-content:space-between;
  position:sticky; top:0; z-index:100;
  box-shadow:0 1px 12px rgba(0,0,0,.04);
}
.topbar-title    { font-size:1.25rem; font-weight:800; color:var(--dark); }
.topbar-subtitle { font-size:.78rem; color:var(--gray); margin-top:.1rem; }
.topbar-right    { display:flex; align-items:center; gap:.75rem; }

/* ── Admin content ──────────────────────────────────────────── */
.admin-content { padding:1.75rem 2rem; flex:1; }

/* ── Stat cards ─────────────────────────────────────────────── */
.stats-grid {
  display:grid; grid-template-columns:repeat(auto-fill,minmax(210px,1fr));
  gap:1.1rem; margin-bottom:1.75rem;
}
.stat-card {
  background:var(--white); border-radius:var(--radius);
  padding:1.4rem; box-shadow:var(--shadow-sm);
  border:1px solid var(--border);
  display:flex; align-items:flex-start; gap:.9rem;
  transition:var(--transition); overflow:hidden; position:relative;
}
.stat-card::after {
  content:''; position:absolute; top:0; right:0;
  width:90px; height:90px; border-radius:50%;
  transform:translate(25%,-25%); opacity:.06;
}
.stat-card-primary::after { background:var(--primary); }
.stat-card-success::after { background:var(--success); }
.stat-card-warning::after { background:var(--warning); }
.stat-card-info::after    { background:var(--secondary); }
.stat-card:hover { transform:translateY(-4px); box-shadow:var(--shadow-glow); }

.stat-icon {
  width:50px; height:50px; border-radius:13px;
  display:flex; align-items:center; justify-content:center;
  font-size:1.45rem; flex-shrink:0;
}
.icon-primary { background:rgba(99,102,241,.1);  color:var(--primary); }
.icon-success { background:rgba(16,185,129,.1);  color:var(--success); }
.icon-warning { background:rgba(245,158,11,.1);  color:var(--warning); }
.icon-info    { background:rgba(6,182,212,.1);   color:var(--secondary); }
.icon-danger  { background:rgba(239,68,68,.1);   color:var(--danger); }

.stat-label { font-size:.72rem; color:var(--gray); font-weight:700; text-transform:uppercase; letter-spacing:.07em; }
.stat-value {
  font-size:2rem; font-weight:900; line-height:1.1; margin-top:.25rem;
  background:linear-gradient(135deg, var(--dark) 30%, var(--primary-dark) 130%);
  -webkit-background-clip:text; -webkit-text-fill-color:transparent; background-clip:text;
}
.stat-change { font-size:.72rem; color:var(--success); font-weight:600; margin-top:.25rem; }

/* ── Admin card ─────────────────────────────────────────────── */
.admin-card {
  background:var(--white); border-radius:var(--radius);
  box-shadow:var(--shadow-sm); border:1px solid var(--border);
  overflow:hidden; margin-bottom:1.4rem;
}
.admin-card-header {
  padding:1.1rem 1.4rem; border-bottom:1px solid var(--border);
  display:flex; align-items:center; justify-content:space-between; flex-wrap:wrap; gap:.75rem;
  background:var(--bg);
}
.admin-card-title { font-size:.95rem; font-weight:700; color:var(--dark); display:flex; align-items:center; gap:.55rem; }
.admin-card-body  { padding:1.4rem; }

/* ── Buttons ─────────────────────────────────────────────────── */
.btn {
  display:inline-flex; align-items:center; gap:7px;
  padding:.58rem 1.2rem; border-radius:var(--radius-sm);
  font-weight:600; font-size:.875rem; cursor:pointer;
  text-decoration:none; border:2px solid transparent;
  transition:var(--transition); white-space:nowrap; letter-spacing:.01em; line-height:1;
}
.btn:focus-visible { outline:3px solid var(--primary-light); outline-offset:2px; }
.btn:disabled { opacity:.55; cursor:not-allowed; transform:none !important; }

.btn-primary { background:linear-gradient(135deg,var(--primary),var(--primary-dark)); color:white; box-shadow:0 4px 12px rgba(99,102,241,.3); }
.btn-primary:hover { transform:translateY(-1px); box-shadow:0 6px 18px rgba(99,102,241,.4); color:white; }
.btn-success { background:linear-gradient(135deg,var(--success),#059669); color:white; box-shadow:0 4px 12px rgba(16,185,129,.25); }
.btn-success:hover { transform:translateY(-1px); color:white; }
.btn-danger  { background:linear-gradient(135deg,var(--danger),#dc2626); color:white; box-shadow:0 4px 12px rgba(239,68,68,.25); }
.btn-danger:hover  { transform:translateY(-1px); color:white; }
.btn-warning { background:linear-gradient(135deg,var(--warning),#d97706); color:white; }
.btn-warning:hover { transform:translateY(-1px); color:white; }
.btn-secondary { background:var(--bg); color:var(--gray); border-color:var(--border); }
.btn-secondary:hover { background:var(--border); color:var(--dark); }
.btn-sm   { padding:.35rem .8rem; font-size:.78rem; }
.btn-block { width:100%; justify-content:center; }

/* ── Table ──────────────────────────────────────────────────── */
.table-wrapper { overflow-x:auto; }
.table { width:100%; border-collapse:collapse; font-size:.875rem; }
.table th {
  background:var(--bg); padding:.85rem 1.1rem; text-align:left;
  font-weight:700; font-size:.73rem; color:var(--gray);
  letter-spacing:.07em; text-transform:uppercase;
  border-bottom:2px solid var(--border); white-space:nowrap;
}
.table td { padding:.9rem 1.1rem; border-bottom:1px solid var(--border); color:var(--dark-2); vertical-align:middle; }
.table tr:last-child td { border-bottom:none; }
.table tr:hover td { background:rgba(99,102,241,.02); }

/* ── Forms ──────────────────────────────────────────────────── */
.form-group { margin-bottom:1.2rem; }
.form-label { display:block; font-weight:600; font-size:.85rem; color:var(--dark-2); margin-bottom:.42rem; }
.form-control,.form-select {
  width:100%; padding:.7rem .95rem;
  border:2px solid var(--border); border-radius:var(--radius-sm);
  font-family:inherit; font-size:.9rem; color:var(--dark);
  background:var(--white); transition:var(--transition); outline:none;
}
.form-control:focus,.form-select:focus { border-color:var(--primary); box-shadow:0 0 0 4px rgba(99,102,241,.1); }
.form-control::placeholder { color:var(--gray-light); }
textarea.form-control { resize:vertical; min-height:90px; }
.form-text { font-size:.78rem; color:var(--gray); margin-top:.35rem; }
.form-grid { display:grid; grid-template-columns:1fr 1fr; gap:1rem; }

/* ── Alerts ─────────────────────────────────────────────────── */
.alert { padding:.85rem 1.1rem; border-radius:var(--radius-sm); margin-bottom:1rem; display:flex; align-items:flex-start; gap:9px; font-size:.875rem; border:1.5px solid; }
.alert-success { background:rgba(16,185,129,.07); border-color:rgba(16,185,129,.25); color:#065f46; }
.alert-danger  { background:rgba(239,68,68,.07);  border-color:rgba(239,68,68,.25);  color:#991b1b; }
.alert-warning { background:rgba(245,158,11,.07); border-color:rgba(245,158,11,.25); color:#92400e; }
.alert-info    { background:rgba(6,182,212,.07);  border-color:rgba(6,182,212,.25);  color:#0e7490; }

/* ── Badges ─────────────────────────────────────────────────── */
.badge { display:inline-flex; align-items:center; gap:4px; padding:.2rem .62rem; border-radius:50px; font-size:.71rem; font-weight:700; letter-spacing:.02em; }
.badge-primary   { background:rgba(99,102,241,.1);  color:var(--primary); }
.badge-success   { background:rgba(16,185,129,.1);  color:var(--success); }
.badge-warning   { background:rgba(245,158,11,.1);  color:var(--warning); }
.badge-danger    { background:rgba(239,68,68,.1);   color:var(--danger); }
.badge-info      { background:rgba(6,182,212,.1);   color:var(--secondary); }
.badge-secondary { background:rgba(100,116,139,.1); color:var(--gray); }

/* ── Modal ──────────────────────────────────────────────────── */
.modal-overlay {
  position:fixed; inset:0; background:rgba(0,0,0,.55);
  backdrop-filter:blur(5px); -webkit-backdrop-filter:blur(5px);
  display:flex; align-items:center; justify-content:center;
  z-index:9999; padding:1rem;
  opacity:0; visibility:hidden; transition:var(--transition);
}
.modal-overlay.active { opacity:1; visibility:visible; }
.modal {
  background:var(--white); border-radius:var(--radius); box-shadow:var(--shadow-xl);
  width:100%; max-width:620px;
  transform:translateY(20px) scale(.97); transition:var(--transition); overflow:hidden;
}
.modal-overlay.active .modal { transform:translateY(0) scale(1); }
.modal-header { padding:1.2rem 1.4rem; border-bottom:1px solid var(--border); display:flex; align-items:center; justify-content:space-between; background:var(--bg); }
.modal-header h3 { font-size:1rem; font-weight:700; }
.modal-close { background:none; border:none; font-size:1.3rem; cursor:pointer; color:var(--gray); line-height:1; padding:.2rem .4rem; border-radius:var(--radius-sm); transition:var(--transition); }
.modal-close:hover { background:var(--border); color:var(--dark); }
.modal-body   { padding:1.4rem; max-height:72vh; overflow-y:auto; }
.modal-footer { padding:.95rem 1.4rem; border-top:1px solid var(--border); display:flex; gap:.7rem; justify-content:flex-end; background:var(--bg); }

/* ── Empty state ────────────────────────────────────────────── */
.empty-state { text-align:center; padding:3rem; color:var(--gray); }
.empty-state-icon { font-size:3rem; margin-bottom:1rem; opacity:.4; }
.empty-state h3 { font-size:1.05rem; font-weight:600; color:var(--dark-2); margin-bottom:.45rem; }

/* ── Utilities ──────────────────────────────────────────────── */
.text-primary { color:var(--primary); } .text-success { color:var(--success); }
.text-danger  { color:var(--danger);  } .text-warning { color:var(--warning); }
.text-gray    { color:var(--gray);    } .text-center  { text-align:center; }
.text-right   { text-align:right;     } .text-sm      { font-size:.8rem; }
.fw-bold      { font-weight:700; }      .fw-semibold  { font-weight:600; }
.mt-1{margin-top:.5rem;} .mt-2{margin-top:1rem;} .mt-3{margin-top:1.5rem;} .mt-4{margin-top:2rem;}
.mb-1{margin-bottom:.5rem;} .mb-2{margin-bottom:1rem;} .mb-3{margin-bottom:1.5rem;}
.d-flex{display:flex;} .align-center{align-items:center;} .justify-between{justify-content:space-between;}
.gap-1{gap:.5rem;} .gap-2{gap:1rem;} .flex-wrap{flex-wrap:wrap;}

/* ── Mobile sidebar toggle ──────────────────────────────────── */
.sidebar-toggle {
  display:none; position:fixed; top:14px; left:14px; z-index:250;
  width:40px; height:40px; border-radius:var(--radius-sm);
  background:var(--white); border:1px solid var(--border); box-shadow:var(--shadow-sm);
  align-items:center; justify-content:center; cursor:pointer; color:var(--dark);
}
.sidebar-backdrop {
  display:none; position:fixed; inset:0; background:rgba(15,23,42,.5); z-index:150;
}
.sidebar-backdrop.open { display:block; }

/* ── Responsive ─────────────────────────────────────────────── */
@media (max-width:1024px) {
  .sidebar { transform:translateX(-100%); }
  .sidebar.open { transform:translateX(0); }
  .admin-main { margin-left:0; }
  .admin-topbar { padding:0 1rem 0 64px; }
  .admin-content { padding:1.2rem; }
  .sidebar-toggle { display:flex; }
}
@media (max-width:640px) {
  .stats-grid { grid-template-columns:1fr 1fr; }
  .form-grid  { grid-template-columns:1fr; }
  .admin-topbar { flex-wrap:wrap; height:auto; min-height:var(--topbar-h); padding:.8rem 1rem .8rem 64px; gap:.5rem; }
  .topbar-title { font-size:1.05rem; }
}

.password-field { position:relative; }
.password-field .form-control { padding-right:2.75rem; }
.password-toggle {
  position:absolute; top:50%; right:.6rem; transform:translateY(-50%);
  background:none; border:none; cursor:pointer; padding:.3rem;
  display:flex; align-items:center; justify-content:center;
  color:var(--gray); border-radius:6px;
}
.password-toggle:hover { color:var(--dark); background:var(--bg); }

/* ── Avatar / profile picture (admin) ───────────────────────── */
.avatar-upload-wrap { position:relative; width:104px; height:104px; margin:0 auto; }
.avatar-upload-wrap img,
.avatar-upload-wrap .avatar-fallback {
  width:104px; height:104px; border-radius:50%; object-fit:cover;
  border:3px solid rgba(99,102,241,.15); display:flex; align-items:center; justify-content:center;
  background:var(--primary); color:#fff; font-weight:800; font-size:2.2rem;
}
.avatar-upload-btn {
  position:absolute; bottom:0; right:0; width:32px; height:32px; border-radius:50%;
  background:var(--primary); color:#fff; display:flex; align-items:center; justify-content:center;
  border:2px solid #fff; cursor:pointer; box-shadow:var(--shadow-sm);
}

/* ── Animations ──────────────────────────────────────────────── */
@keyframes fadeInUp {
  from { opacity:0; transform:translateY(14px); }
  to   { opacity:1; transform:translateY(0); }
}
@keyframes popIn {
  from { opacity:0; transform:scale(.94); }
  to   { opacity:1; transform:scale(1); }
}
.admin-card, .stat-card { animation: fadeInUp .45s cubic-bezier(.16,1,.3,1) both; }
.alert { animation: fadeInUp .35s ease both; }
.modal { animation: popIn .25s cubic-bezier(.34,1.56,.64,1) both; }
.btn:active { transform: scale(.96); }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
}

/* ── Accessibility ───────────────────────────────────────────── */
a:focus-visible, button:focus-visible, input:focus-visible,
select:focus-visible, textarea:focus-visible, [tabindex]:focus-visible {
  outline: 3px solid var(--primary); outline-offset: 2px;
}
.sr-only {
  position:absolute; width:1px; height:1px; padding:0; margin:-1px;
  overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; border:0;
}

/* ── Dark mode ───────────────────────────────────────────────── */
html[data-theme="dark"] {
  --dark:       #f1f5f9;
  --dark-2:     #e2e8f0;
  --dark-3:     #cbd5e1;
  --gray:       #94a3b8;
  --gray-light: #64748b;
  --border:     #334155;
  --bg:         #0b1120;
  --white:      #16213a;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.35),0 1px 2px rgba(0,0,0,.25);
  --shadow-md: 0 4px 12px rgba(0,0,0,.4),0 2px 4px rgba(0,0,0,.25);
  --shadow-lg: 0 20px 40px rgba(0,0,0,.5);
  --shadow-xl: 0 32px 64px rgba(0,0,0,.55);
}
html[data-theme="dark"] body { background:var(--bg); color:var(--dark); }
html[data-theme="dark"] input, html[data-theme="dark"] select, html[data-theme="dark"] textarea {
  background:var(--white); color:var(--dark); border-color:var(--border);
}

.theme-toggle {
  background:none; border:1px solid var(--border); cursor:pointer;
  width:36px; height:36px; border-radius:50%; display:flex; align-items:center; justify-content:center;
  color:var(--gray); transition:var(--transition);
}
.theme-toggle:hover { background:var(--bg); color:var(--dark); }