/* ══════════════════════════════════════════════════════
   QuizForge — Student UI  (Light / Professional)
   ══════════════════════════════════════════════════════ */
@import url('https://fonts.googleapis.com/css2?family=Poppins:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;0,900;1,400&family=DM+Mono:wght@400;500&display=swap');

:root {
  --bg:       #eef2f7;
  --surf:     #ffffff;
  --s2:       #f5f7fa;
  --bdr:      #d0d9e8;
  --bdr-bold: #a0aec0;
  --acc:      #1a73e8;
  --acc-dk:   #1558b0;
  --teal:     #00897b;
  --amber:    #f57c00;
  --text:     #1a1a2e;
  --text2:    #3d4a5c;
  --muted:    #64748b;
  --ok:       #16a34a;
  --err:      #dc2626;
  --shadow:   0 2px 16px rgba(0,0,0,.09);
  --shadow-lg:0 8px 40px rgba(0,0,0,.13);
  --radius:   14px;
  --radius-sm:10px;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; -webkit-font-smoothing: antialiased; }
body { font-family: 'Poppins', sans-serif; background: var(--bg); color: var(--text); }
a { color: var(--acc); }

/* ── Typography ── */
.h1 { font-family: 'Poppins', sans-serif; font-size: 28px; font-weight: 800; color: var(--text); }
.h2 { font-family: 'Poppins', sans-serif; font-size: 18px; font-weight: 700; color: var(--text); }
.label { font-family: 'DM Mono', monospace; font-size: 10px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.mono  { font-family: 'DM Mono', monospace; }

/* ── Sidebar Layout ── */
.qf-wrap   { display: flex; min-height: 100vh; }
.qf-sidebar {
  width: 260px; flex-shrink: 0;
  background: var(--surf);
  border-right: 2px solid var(--bdr);
  display: flex; flex-direction: column;
  position: fixed; top: 0; left: 0; bottom: 0; z-index: 200;
}
.qf-main { margin-left: 260px; flex: 1; display: flex; flex-direction: column; min-height: 100vh; }

/* Sidebar logo */
.sb-logo { padding: 24px; border-bottom: 2px solid var(--bdr); }
.sb-logo-text {
  font-family: 'Poppins', sans-serif; font-size: 22px; font-weight: 800;
  color: var(--acc); display: block; letter-spacing: -.3px;
}
.sb-logo-sub {
  font-family: 'DM Mono', monospace; font-size: 9px; letter-spacing: .12em;
  text-transform: uppercase; color: var(--muted); margin-top: 3px; display: block;
}

/* Sidebar student */
.sb-student {
  padding: 16px 20px; border-bottom: 2px solid var(--bdr);
  display: flex; align-items: center; gap: 12px;
}
.sb-av {
  width: 44px; height: 44px; border-radius: 12px;
  background: linear-gradient(135deg, var(--acc), #0d47a1);
  display: flex; align-items: center; justify-content: center;
  font-size: 22px; flex-shrink: 0; border: 2px solid var(--bdr);
}
.sb-name  { font-size: 13px; font-weight: 700; color: var(--text); line-height: 1.3; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.sb-email { font-size: 11px; color: var(--muted); margin-top: 2px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* Nav */
.sb-nav { flex: 1; padding: 14px 12px; overflow-y: auto; }
.sb-section { font-family: 'DM Mono', monospace; font-size: 9px; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); padding: 10px 12px 6px; }
.sb-link {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 14px; border-radius: var(--radius-sm);
  font-size: 13px; font-weight: 600; color: var(--muted);
  text-decoration: none; transition: all .15s; margin-bottom: 3px;
  border: 2px solid transparent;
}
.sb-link:hover { color: var(--text); background: var(--s2); border-color: var(--bdr); }
.sb-link.active {
  color: var(--acc); background: #e8f0fd;
  border-color: #b8d0f8; font-weight: 700;
}
.sb-icon { width: 20px; text-align: center; font-size: 17px; flex-shrink: 0; }
.sb-footer { padding: 14px 12px; border-top: 2px solid var(--bdr); }
.sb-logout {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 14px; border-radius: var(--radius-sm);
  font-size: 13px; font-weight: 600; color: var(--muted);
  text-decoration: none; transition: all .15s; width: 100%;
  border: 2px solid transparent; background: transparent; cursor: pointer;
}
.sb-logout:hover { color: var(--err); background: #fef2f2; border-color: #fecaca; }

/* Topbar */
.topbar {
  background: var(--surf); border-bottom: 2px solid var(--bdr);
  padding: 0 28px; height: 64px;
  display: flex; align-items: center; justify-content: space-between;
  position: sticky; top: 0; z-index: 100; box-shadow: 0 1px 0 var(--bdr);
}
.topbar-title { font-family: 'Poppins', sans-serif; font-size: 17px; font-weight: 800; display: flex; align-items: center; gap: 8px; }
.topbar-right { display: flex; align-items: center; gap: 10px; }
.topbar-time {
  font-family: 'DM Mono', monospace; font-size: 12px; color: var(--muted);
  background: var(--s2); border: 2px solid var(--bdr);
  padding: 5px 12px; border-radius: 8px; font-weight: 500;
}
.topbar-btn {
  background: var(--acc); color: #fff; border: none;
  padding: 8px 16px; border-radius: 8px; font-size: 12px;
  font-weight: 700; cursor: pointer; text-decoration: none;
  display: inline-flex; align-items: center; gap: 6px;
}
.topbar-btn:hover { background: var(--acc-dk); }

/* Page body */
.pg-body { flex: 1; padding: 28px; }

/* ── Cards ── */
.card {
  background: var(--surf); border: 2px solid var(--bdr);
  border-radius: var(--radius); box-shadow: var(--shadow);
  overflow: hidden;
}
.card-hdr {
  padding: 16px 22px; border-bottom: 2px solid var(--bdr);
  display: flex; align-items: center; justify-content: space-between;
  background: var(--s2);
}
.card-hdr h2 { font-family: 'Poppins', sans-serif; font-size: 14px; font-weight: 800; color: var(--text); display: flex; align-items: center; gap: 8px; }
.card-body { padding: 22px; }

/* ── Stat cards ── */
.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 14px; margin-bottom: 24px; }
.stat-card {
  background: var(--surf); border: 2px solid var(--bdr);
  border-radius: var(--radius); padding: 20px;
  position: relative; overflow: hidden;
  box-shadow: var(--shadow);
}
.stat-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: var(--c, var(--acc)); }
.stat-num  { font-family: 'Poppins', sans-serif; font-size: 28px; font-weight: 800; color: var(--text); line-height: 1; margin-bottom: 5px; }
.stat-lbl  { font-family: 'DM Mono', monospace; font-size: 10px; letter-spacing: .08em; text-transform: uppercase; color: var(--muted); }
.stat-icon { position: absolute; top: 16px; right: 16px; font-size: 22px; opacity: .2; }

/* ── Forms ── */
.fg { margin-bottom: 18px; }
.fg > label {
  display: block; font-family: 'DM Mono', monospace; font-size: 10px;
  letter-spacing: .1em; text-transform: uppercase; color: var(--muted);
  margin-bottom: 7px; font-weight: 500;
}
.fg .hint { font-size: 11px; color: var(--muted); margin-top: 5px; }
.inp {
  width: 100%; background: var(--surf); border: 2px solid var(--bdr);
  border-radius: var(--radius-sm); padding: 12px 16px;
  color: var(--text); font-family: 'Poppins', sans-serif; font-size: 14px;
  font-weight: 500; outline: none; transition: border-color .2s, box-shadow .2s;
}
.inp:focus { border-color: var(--acc); box-shadow: 0 0 0 3px rgba(26,115,232,.12); }
.inp:read-only { background: var(--s2); color: var(--muted); cursor: not-allowed; }
.inp::placeholder { color: #b0bec5; }
.pw-wrap { position: relative; }
.pw-wrap .inp { padding-right: 46px; }
.pw-eye { position: absolute; right: 14px; top: 50%; transform: translateY(-50%); background: none; border: none; cursor: pointer; color: var(--muted); font-size: 16px; padding: 4px; }
.pw-eye:hover { color: var(--text); }

/* ── Buttons ── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 24px; border-radius: var(--radius-sm);
  font-family: 'Poppins', sans-serif; font-size: 14px; font-weight: 700;
  cursor: pointer; text-decoration: none; border: 2px solid transparent;
  transition: all .15s; white-space: nowrap; letter-spacing: .01em;
}
.btn-primary { background: var(--acc); color: #fff; border-color: var(--acc); }
.btn-primary:hover { background: var(--acc-dk); border-color: var(--acc-dk); box-shadow: 0 4px 14px rgba(26,115,232,.35); }
.btn-full { width: 100%; }
.btn-outline { background: #fff; border-color: var(--bdr-bold); color: var(--text); }
.btn-outline:hover { border-color: var(--acc); color: var(--acc); background: #e8f0fd; }
.btn-danger { background: #fff; border-color: #fca5a5; color: var(--err); }
.btn-danger:hover { background: #fef2f2; border-color: #f87171; }
.btn-sm { padding: 8px 14px; font-size: 12px; }

/* ── Alerts ── */
.alert { padding: 13px 16px; border-radius: var(--radius-sm); font-size: 13px; margin-bottom: 20px; border: 2px solid; display: flex; align-items: flex-start; gap: 10px; font-weight: 500; }
.alert-ok  { background: #f0fdf4; border-color: #86efac; color: #15803d; }
.alert-err { background: #fef2f2; border-color: #fca5a5; color: #b91c1c; }

/* ── Table ── */
.tbl-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th { padding: 11px 16px; font-family: 'DM Mono', monospace; font-size: 10px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); text-align: left; border-bottom: 2px solid var(--bdr); background: var(--s2); white-space: nowrap; }
td { padding: 13px 16px; font-size: 13px; border-bottom: 2px solid var(--bdr); vertical-align: middle; font-weight: 500; }
tr:last-child td { border-bottom: none; }
tbody tr:hover td { background: #f0f7ff; }

/* ── Badges ── */
.badge { display: inline-flex; align-items: center; padding: 3px 10px; border-radius: 20px; font-size: 10px; font-family: 'DM Mono', monospace; letter-spacing: .05em; font-weight: 700; border: 2px solid; }
.badge-pass { background: #f0fdf4; color: #16a34a; border-color: #86efac; }
.badge-fail { background: #fef2f2; color: #dc2626; border-color: #fca5a5; }
.badge-subj { background: #eff6ff; color: #1d4ed8; border-color: #bfdbfe; }
.badge-easy { background: #f0fdf4; color: #16a34a; border-color: #86efac; }
.badge-medium { background: #fff7ed; color: #c2410c; border-color: #fed7aa; }
.badge-hard  { background: #fef2f2; color: #dc2626; border-color: #fca5a5; }

/* ── Score bar ── */
.score-bar { display: inline-block; width: 60px; height: 5px; border-radius: 3px; background: var(--bdr); vertical-align: middle; overflow: hidden; margin-left: 8px; border: 1px solid var(--bdr); }
.score-fill { height: 100%; border-radius: 3px; }

/* ── Section heading ── */
.pg-header { margin-bottom: 22px; }
.pg-header h1 { font-family: 'Poppins', sans-serif; font-size: 24px; font-weight: 800; }
.pg-header p  { color: var(--muted); font-size: 14px; margin-top: 5px; font-weight: 500; }

/* ── Empty state ── */
.empty { padding: 48px 24px; text-align: center; color: var(--muted); }
.empty-icon { font-size: 40px; margin-bottom: 12px; }
.empty h3 { font-family: 'Poppins', sans-serif; font-size: 16px; color: var(--text); margin-bottom: 6px; font-weight: 700; }

/* ── Divider ── */
.divider { display: flex; align-items: center; gap: 12px; color: var(--muted); font-size: 12px; margin: 20px 0; font-weight: 600; }
.divider::before, .divider::after { content: ''; flex: 1; height: 2px; background: var(--bdr); }

/* ── Mobile ── */
.sb-hamburger { display: none; position: fixed; top: 14px; left: 14px; z-index: 300; background: var(--surf); border: 2px solid var(--bdr); border-radius: 10px; padding: 8px 10px; cursor: pointer; font-size: 18px; line-height: 1; box-shadow: var(--shadow); }
.sb-overlay  { display: none; position: fixed; inset: 0; background: rgba(0,0,0,.35); z-index: 150; }
@media(max-width:768px){
  .qf-sidebar { transform: translateX(-100%); transition: transform .25s; }
  .qf-sidebar.open { transform: translateX(0); }
  .qf-main { margin-left: 0; }
  .topbar { padding: 0 16px 0 54px; }
  .pg-body { padding: 16px; }
  .sb-hamburger { display: block; }
  .sb-overlay.show { display: block; }
}

/* ── Auth pages ── */
.auth-page { min-height: 100vh; background: var(--bg); display: flex; align-items: center; justify-content: center; padding: 32px 20px; }
.auth-page::before { content: ''; position: fixed; inset: 0; background: linear-gradient(135deg, #e8f0fd 0%, #f0f4f8 50%, #e8f5e9 100%); z-index: -1; }
.auth-card {
  width: 100%; max-width: 460px;
  background: var(--surf); border: 2px solid var(--bdr);
  border-radius: 20px; box-shadow: var(--shadow-lg); overflow: hidden;
}
.auth-header {
  background: linear-gradient(135deg, var(--acc) 0%, #0d47a1 100%);
  padding: 28px 32px; text-align: center;
}
.auth-logo { font-family: 'Poppins', sans-serif; font-size: 26px; font-weight: 800; color: #fff; display: block; letter-spacing: -.3px; }
.auth-logo-sub { font-family: 'DM Mono', monospace; font-size: 10px; letter-spacing: .14em; text-transform: uppercase; color: rgba(255,255,255,.7); margin-top: 4px; display: block; }
.auth-body { padding: 32px; }
.auth-title { font-family: 'Poppins', sans-serif; font-size: 22px; font-weight: 800; margin-bottom: 5px; }
.auth-sub   { color: var(--muted); font-size: 13px; margin-bottom: 26px; line-height: 1.6; font-weight: 500; }
.auth-footer { padding: 18px 32px; border-top: 2px solid var(--bdr); background: var(--s2); text-align: center; font-size: 13px; color: var(--muted); font-weight: 500; }
.auth-footer a { color: var(--acc); font-weight: 700; text-decoration: none; }
.auth-footer a:hover { text-decoration: underline; }