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

:root {
  --bg:        #08080f;
  --surface:   #10101a;
  --card:      #17172a;
  --card-2:    #1e1e32;
  --border:    #2a2a45;
  --border-2:  #3a3a55;
  --text:      #f0f0ff;
  --muted:     #7070a0;
  --muted-2:   #9090bb;
  --accent:    #8b5cf6;
  --accent-2:  #a78bfa;
  --blue:      #3b82f6;
  --green:     #10b981;
  --gold:      #f59e0b;
  --orange:    #f97316;
  --red:       #ef4444;
  --sidebar-w: 220px;
  --radius:    10px;
  --transition: 150ms ease;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 15px; }

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
}

/* ── Sidebar ── */
.sidebar {
  width: var(--sidebar-w);
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0; left: 0; bottom: 0;
  z-index: 100;
  padding: 0;
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 20px 18px 18px;
  border-bottom: 1px solid var(--border);
  text-decoration: none;
}

.sidebar-logo .logo-mark {
  width: 32px; height: 32px;
  background: linear-gradient(135deg, var(--accent), #6d28d9);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 1rem; color: #fff;
  flex-shrink: 0;
}

.sidebar-logo .logo-name {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  color: var(--text);
}

.sidebar-logo .logo-name span {
  color: var(--accent-2);
  font-style: italic;
}

.sidebar-nav {
  flex: 1;
  padding: 12px 10px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  overflow-y: auto;
}

.nav-section {
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--muted);
  text-transform: uppercase;
  padding: 12px 8px 6px;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  border-radius: 7px;
  color: var(--muted-2);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
  transition: background var(--transition), color var(--transition);
}

.nav-link svg { width: 16px; height: 16px; flex-shrink: 0; }

.nav-link:hover {
  background: var(--card);
  color: var(--text);
}

.nav-link.active {
  background: rgba(139,92,246,0.15);
  color: var(--accent-2);
}

.nav-link.active svg { color: var(--accent); }

.sidebar-user {
  padding: 14px 16px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 10px;
}

.user-avatar {
  width: 30px; height: 30px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--blue));
  display: flex; align-items: center; justify-content: center;
  font-size: 0.7rem; font-weight: 700; color: #fff;
  flex-shrink: 0;
}

.user-info { flex: 1; min-width: 0; }
.user-name  { font-size: 0.82rem; font-weight: 600; truncate; }
.user-plan  { font-size: 0.68rem; color: var(--muted); margin-top: 1px; }
.user-plan.pro { color: var(--gold); }

.btn-logout {
  background: none; border: none; cursor: pointer;
  color: var(--muted); padding: 4px;
  border-radius: 5px; transition: color var(--transition);
}
.btn-logout:hover { color: var(--red); }

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

.page-header {
  padding: 24px 32px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.page-title {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text);
}

.page-subtitle {
  font-size: 0.82rem;
  color: var(--muted);
  margin-top: 2px;
}

.page-body {
  padding: 24px 32px 48px;
  flex: 1;
}

/* ── Cards ── */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}

.card-sm { padding: 14px 16px; }

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  gap: 12px;
}

.card-title {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text);
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border-radius: 7px;
  border: 1px solid transparent;
  font-size: 0.82rem;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.btn-primary:hover { background: #7c3aed; border-color: #7c3aed; }

.btn-ghost {
  background: transparent;
  color: var(--muted-2);
  border-color: var(--border-2);
}
.btn-ghost:hover { background: var(--card-2); color: var(--text); }

.btn-danger {
  background: transparent;
  color: var(--red);
  border-color: var(--border);
}
.btn-danger:hover { background: rgba(239,68,68,0.1); }

.btn-sm { padding: 4px 10px; font-size: 0.76rem; border-radius: 5px; }
.btn-lg { padding: 10px 20px; font-size: 0.92rem; }

/* ── Inputs ── */
.form-group { display: flex; flex-direction: column; gap: 5px; }

.form-label {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--muted-2);
}

.form-control {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 7px;
  padding: 8px 12px;
  color: var(--text);
  font-size: 0.88rem;
  font-family: inherit;
  transition: border-color var(--transition);
  width: 100%;
}

.form-control:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(139,92,246,0.15);
}

.form-control::placeholder { color: var(--muted); }

select.form-control option { background: var(--card); }

textarea.form-control { resize: vertical; min-height: 80px; }

.form-row {
  display: grid;
  gap: 14px;
}
.form-row-2 { grid-template-columns: 1fr 1fr; }
.form-row-3 { grid-template-columns: 1fr 1fr 1fr; }
.form-row-4 { grid-template-columns: 1fr 1fr 1fr 1fr; }

/* ── Flash messages ── */
.flash-container { padding: 0 32px; }
.flash {
  padding: 10px 14px;
  border-radius: 7px;
  font-size: 0.82rem;
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.flash-success { background: rgba(16,185,129,0.12); border: 1px solid rgba(16,185,129,0.3); color: #34d399; }
.flash-error   { background: rgba(239,68,68,0.12);  border: 1px solid rgba(239,68,68,0.3);  color: #f87171; }

/* ── Stat cards (dashboard) ── */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 14px;
}

.stat-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
  position: relative;
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  border-radius: var(--radius) var(--radius) 0 0;
}

.stat-card.fm::before  { background: #8b5cf6; }
.stat-card.math::before { background: #3b82f6; }
.stat-card.phys::before { background: #10b981; }
.stat-card.total::before { background: linear-gradient(90deg, #8b5cf6, #3b82f6, #10b981); }

.stat-value {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
  color: var(--text);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 0.78rem;
  color: var(--muted);
  font-weight: 500;
}

/* ── Paper matrix ── */
.matrix-section { margin-bottom: 32px; }

.matrix-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
}

.subject-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
}

.matrix-title { font-size: 0.95rem; font-weight: 600; }
.matrix-board { font-size: 0.78rem; color: var(--muted); margin-left: 2px; }

.matrix-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 4px;
}

.matrix-table th {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--muted);
  text-align: center;
  padding: 4px 6px;
  letter-spacing: 0.03em;
}

.matrix-table td:first-child {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--muted-2);
  padding-right: 10px;
  white-space: nowrap;
}

.matrix-cell {
  width: 64px;
  height: 44px;
  border-radius: 6px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-size: 0.72rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--muted);
  transition: all var(--transition);
  position: relative;
}

.matrix-cell:hover { border-color: var(--accent); background: var(--card-2); color: var(--text); }
.matrix-cell.done  { border-color: transparent; color: #fff; }

.matrix-cell .cell-pct  { font-size: 0.78rem; font-weight: 700; line-height: 1; }
.matrix-cell .cell-grade { font-size: 0.6rem; opacity: 0.85; margin-top: 1px; }

/* ── Heatmap grid ── */
.heatmap-container { overflow-x: auto; }

.heatmap-table {
  border-collapse: separate;
  border-spacing: 3px;
  font-size: 0.75rem;
}

.heatmap-table th {
  color: var(--muted);
  font-weight: 500;
  padding: 4px 6px;
  text-align: center;
}

.heatmap-table td.row-label {
  font-weight: 600;
  color: var(--muted-2);
  padding-right: 10px;
  white-space: nowrap;
  font-size: 0.78rem;
}

.hm-cell {
  width: 38px;
  height: 30px;
  border-radius: 5px;
  text-align: center;
  vertical-align: middle;
  font-size: 0.68rem;
  font-weight: 600;
  cursor: default;
  border: 1px solid rgba(0,0,0,0.2);
  transition: transform var(--transition);
}

.hm-cell:hover { transform: scale(1.15); z-index: 10; position: relative; }
.hm-cell.empty { background: var(--card); color: var(--muted); border: 1px solid var(--border); }

.hm-cell.pct-90 { background: #14b8a6; color: #fff; }
.hm-cell.pct-80 { background: #22c55e; color: #fff; }
.hm-cell.pct-70 { background: #84cc16; color: #1a2e05; }
.hm-cell.pct-60 { background: #eab308; color: #1a1a00; }
.hm-cell.pct-50 { background: #f97316; color: #fff; }
.hm-cell.pct-0  { background: #ef4444; color: #fff; }

/* ── Grade badge ── */
.grade-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px; height: 28px;
  border-radius: 6px;
  font-size: 0.78rem;
  font-weight: 700;
}

/* ── Paper entry form ── */
.entry-section {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 24px;
  margin-bottom: 20px;
}

.entry-section-title {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.07em;
  margin-bottom: 16px;
}

.q-row {
  display: grid;
  grid-template-columns: 70px 1fr 90px 1fr 28px;
  gap: 8px;
  align-items: center;
  margin-bottom: 8px;
}

.q-row .q-sep { text-align: center; color: var(--muted); font-size: 0.9rem; }

.q-total {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--border);
}

.q-total-label { font-size: 0.85rem; color: var(--muted-2); }
.q-total-value { font-size: 1.4rem; font-weight: 700; color: var(--text); }
.q-total-pct   { font-size: 0.85rem; color: var(--muted); }
.q-grade-preview { margin-left: auto; }

/* ── Recent paper list ── */
.paper-row {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 11px 14px;
  border-radius: 7px;
  border: 1px solid var(--border);
  background: var(--card);
  transition: background var(--transition);
  text-decoration: none;
  color: inherit;
  margin-bottom: 6px;
}

.paper-row:hover { background: var(--card-2); }

.paper-subject-bar {
  width: 4px;
  height: 36px;
  border-radius: 2px;
  flex-shrink: 0;
}

.paper-info { flex: 1; min-width: 0; }
.paper-name { font-size: 0.88rem; font-weight: 600; }
.paper-meta { font-size: 0.74rem; color: var(--muted); margin-top: 2px; }

.paper-score { text-align: right; }
.paper-pct  { font-size: 1.1rem; font-weight: 700; }
.paper-raw  { font-size: 0.72rem; color: var(--muted); margin-top: 1px; }

/* ── Progress bar ── */
.progress-bar-track {
  height: 6px;
  background: var(--card-2);
  border-radius: 3px;
  overflow: hidden;
  margin-top: 6px;
}

.progress-bar-fill {
  height: 100%;
  border-radius: 3px;
  transition: width 0.4s ease;
}

/* ── Bank cards ── */
.upload-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
  color: inherit;
  transition: background var(--transition);
  margin-bottom: 8px;
}

.upload-card:hover { background: var(--card-2); }

.file-icon {
  width: 38px; height: 38px;
  background: var(--card-2);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  color: var(--accent); font-size: 1rem; flex-shrink: 0;
}

.topic-pill {
  display: inline-flex;
  padding: 2px 8px;
  border-radius: 100px;
  font-size: 0.7rem;
  font-weight: 500;
  background: rgba(139,92,246,0.15);
  color: var(--accent-2);
  border: 1px solid rgba(139,92,246,0.25);
  margin: 2px;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition);
}
.topic-pill:hover, .topic-pill.active {
  background: rgba(139,92,246,0.3);
  color: #fff;
}

/* ── Subscription ── */
.plan-card {
  border: 2px solid var(--border);
  border-radius: 12px;
  padding: 28px;
  text-align: center;
  transition: border-color var(--transition);
}

.plan-card.pro {
  border-color: var(--accent);
  background: rgba(139,92,246,0.05);
}

.plan-price { font-size: 2.8rem; font-weight: 700; color: var(--text); line-height: 1; }
.plan-period { font-size: 0.85rem; color: var(--muted); }
.plan-name { font-size: 1rem; font-weight: 600; margin-bottom: 8px; }

.plan-feature { font-size: 0.85rem; color: var(--muted-2); padding: 5px 0; display: flex; align-items: center; gap: 8px; }
.plan-feature svg { color: var(--green); flex-shrink: 0; }

/* ── Auth pages ── */
.auth-wrap {
  min-height: 100vh;
  background: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.auth-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 40px;
  width: 100%;
  max-width: 420px;
}

.auth-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 28px;
}

.auth-title { font-size: 1.3rem; font-weight: 700; margin-bottom: 6px; }
.auth-subtitle { font-size: 0.82rem; color: var(--muted); }

.auth-link { color: var(--accent-2); text-decoration: none; }
.auth-link:hover { text-decoration: underline; }

/* ── Divider ── */
.divider {
  height: 1px;
  background: var(--border);
  margin: 20px 0;
}

/* ── Tooltip ── */
[data-tip] { position: relative; }
[data-tip]:hover::after {
  content: attr(data-tip);
  position: absolute;
  bottom: calc(100% + 6px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--card-2);
  border: 1px solid var(--border);
  color: var(--text);
  font-size: 0.72rem;
  white-space: nowrap;
  padding: 4px 8px;
  border-radius: 5px;
  pointer-events: none;
  z-index: 50;
}

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-2); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--muted); }

/* ── Responsive ── */
@media (max-width: 768px) {
  :root { --sidebar-w: 0px; }
  .sidebar { display: none; }
  .page-header, .page-body { padding-left: 16px; padding-right: 16px; }
  .form-row-3, .form-row-4 { grid-template-columns: 1fr 1fr; }
  .q-row { grid-template-columns: 60px 1fr 80px; }
  .q-row .q-sep, .q-row .q-topic { display: none; }
}