:root {
  --primary: #253d7a;
  --primary-dark: #182a57;
  --accent: #009688;
  --accent-dark: #00796b;
  --bg: #f5f7fb;
  --card-bg: #ffffff;
  --border: #e3e7ef;
  --text: #1c2333;
  --text-muted: #64708a;
  --danger: #d64545;
  --success: #1f9d55;
  --warning: #b8860b;
  --radius: 10px;
  --shadow: 0 1px 3px rgba(20, 26, 46, 0.08), 0 1px 2px rgba(20, 26, 46, 0.06);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }
.container-narrow { max-width: 480px; margin: 0 auto; padding: 0 20px; }

/* ---- Top nav ---- */
.navbar {
  background: var(--primary);
  color: #fff;
  padding: 0 20px;
}
.navbar .inner {
  max-width: 1080px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}
.navbar .brand { font-weight: 700; font-size: 18px; color: #fff; letter-spacing: 0.3px; }
.navbar .brand:hover { text-decoration: none; }
.navbar nav { display: flex; gap: 4px; align-items: center; }
.navbar nav a {
  color: rgba(255,255,255,0.85);
  padding: 8px 12px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 500;
}
.navbar nav a:hover, .navbar nav a.active {
  color: #fff;
  background: rgba(255,255,255,0.12);
  text-decoration: none;
}
.navbar .logout-btn {
  background: transparent;
  border: 1px solid rgba(255,255,255,0.35);
  color: #fff;
  padding: 7px 14px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 14px;
}
.navbar .logout-btn:hover { background: rgba(255,255,255,0.12); }

.admin-badge {
  background: var(--accent);
  color: #fff;
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 20px;
  margin-left: 8px;
  vertical-align: middle;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* ---- Page shell ---- */
.page { padding: 32px 0 64px; }
.page-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 24px; flex-wrap: wrap; gap: 12px; }
.page-header h1 { font-size: 24px; margin: 0; }
.page-header p.subtitle { color: var(--text-muted); margin: 4px 0 0; }

/* ---- Cards ---- */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-bottom: 20px;
}
.card h2 { font-size: 17px; margin: 0 0 16px; }
.card h3 { font-size: 15px; margin: 20px 0 8px; }

.grid { display: grid; gap: 20px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 800px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* ---- Stat tiles ---- */
.stat-tile { background: var(--card-bg); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px 20px; box-shadow: var(--shadow); }
.stat-tile .label { color: var(--text-muted); font-size: 13px; margin-bottom: 6px; }
.stat-tile .value { font-size: 26px; font-weight: 700; }

/* ---- Forms ---- */
label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 6px; color: var(--text); }
input[type=text], input[type=email], input[type=password], input[type=number], input[type=url],
select, textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
  background: #fff;
  color: var(--text);
  font-family: inherit;
}
textarea { resize: vertical; }
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 61, 122, 0.12);
}
.field { margin-bottom: 16px; }
.field-inline { display: flex; align-items: center; gap: 8px; }
.field-inline label { margin: 0; }
.help-text { color: var(--text-muted); font-size: 12.5px; margin-top: 4px; }

.btn {
  display: inline-block;
  padding: 10px 18px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  text-align: center;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); text-decoration: none; }
.btn-accent { background: var(--accent); color: #fff; }
.btn-accent:hover { background: var(--accent-dark); text-decoration: none; }
.btn-outline { background: #fff; border-color: var(--border); color: var(--text); }
.btn-outline:hover { border-color: var(--primary); text-decoration: none; }
.btn-danger { background: #fff; color: var(--danger); border-color: var(--danger); }
.btn-danger:hover { background: var(--danger); color: #fff; text-decoration: none; }
.btn-sm { padding: 6px 12px; font-size: 13px; }
.btn:disabled { opacity: 0.55; cursor: not-allowed; }

/* ---- Alerts ---- */
.alert { padding: 12px 16px; border-radius: 8px; margin-bottom: 18px; font-size: 14px; }
.alert-error { background: #fdecec; color: #9c2a2a; border: 1px solid #f5c6c6; }
.alert-success { background: #e9f9ee; color: #1c6b3c; border: 1px solid #bfeccd; }
.alert-warning { background: #fdf6e3; color: #7a5c00; border: 1px solid #f2e2a0; }

/* ---- Tables ---- */
table { width: 100%; border-collapse: collapse; font-size: 13.5px; }
th, td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); }
th { color: var(--text-muted); font-weight: 600; font-size: 12px; text-transform: uppercase; letter-spacing: 0.4px; }
tr:last-child td { border-bottom: none; }
.table-wrap { overflow-x: auto; }

/* ---- Badges ---- */
.badge { display: inline-block; padding: 3px 10px; border-radius: 20px; font-size: 12px; font-weight: 600; }
.badge-gray { background: #eef0f5; color: var(--text-muted); }
.badge-green { background: #e4f8ea; color: var(--success); }
.badge-red { background: #fdecec; color: var(--danger); }
.badge-blue { background: #e8edfb; color: var(--primary); }
.badge-yellow { background: #fdf6e3; color: var(--warning); }

/* ---- Pricing cards ---- */
.plan-card { border: 2px solid var(--border); border-radius: var(--radius); padding: 24px; background: #fff; display: flex; flex-direction: column; }
.plan-card.current { border-color: var(--accent); }
.plan-card .plan-name { font-size: 18px; font-weight: 700; margin-bottom: 4px; }
.plan-card .plan-price { font-size: 32px; font-weight: 800; margin: 8px 0 16px; }
.plan-card .plan-price span { font-size: 14px; font-weight: 500; color: var(--text-muted); }
.plan-card ul { list-style: none; padding: 0; margin: 0 0 20px; flex: 1; }
.plan-card li { padding: 6px 0; font-size: 14px; color: var(--text); }
.plan-card li.disabled { color: var(--text-muted); text-decoration: line-through; }

/* ---- Steps / status ---- */
.status-steps { display: flex; flex-wrap: wrap; gap: 8px; margin: 20px 0; }
.status-step { padding: 8px 14px; border-radius: 20px; font-size: 13px; background: #eef0f5; color: var(--text-muted); }
.status-step.active { background: var(--primary); color: #fff; }
.status-step.done { background: #e4f8ea; color: var(--success); }
.status-step.failed { background: #fdecec; color: var(--danger); }

.spinner {
  width: 18px; height: 18px; border: 3px solid #d7dcea; border-top-color: var(--primary);
  border-radius: 50%; display: inline-block; animation: spin 0.8s linear infinite; vertical-align: middle;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---- Study pack content ---- */
.chapter-block { border-left: 3px solid var(--accent); padding-left: 16px; margin-bottom: 24px; }
.quiz-question { background: #f8f9fc; border-radius: 8px; padding: 14px 16px; margin-bottom: 12px; }
.flashcard { background: #fff; border: 1px solid var(--border); border-radius: 8px; padding: 14px 16px; margin-bottom: 10px; }
.code-block { background: #1c2333; color: #e7ecf7; padding: 14px 16px; border-radius: 8px; overflow-x: auto; font-family: "SFMono-Regular", Consolas, Menlo, monospace; font-size: 13px; white-space: pre-wrap; }

.empty-state { text-align: center; padding: 40px 20px; color: var(--text-muted); }

footer.site-footer { text-align: center; color: var(--text-muted); font-size: 13px; padding: 30px 0; }