:root {
  --bg: #f5fbf7;
  --surface: #ffffff;
  --surface-soft: #f6fdf9;
  --text: #234338;
  --muted: #5f7a6f;
  --p-blue: #d9efe7;
  --p-green: #d8f3e3;
  --p-lila: #e6f6ee;
  --accent: #72c8a1;
  --accent-strong: #57af89;
  --border: #d7ede2;
  --shadow: 0 10px 28px rgba(39, 95, 72, 0.12);
}

[data-theme="dark"] {
  --bg: #0b1220;
  --surface: #121a2b;
  --surface-soft: #162136;
  --text: #e5edf9;
  --muted: #9fb1cc;
  --accent: #5ea782;
  --accent-strong: #79cda1;
  --border: #25344f;
  --shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
}

* { box-sizing: border-box; }
body { margin: 0; font-family: var(--font-family-custom, "Segoe UI", "Trebuchet MS", sans-serif); color: var(--text); background: var(--bg); }
.topbar { display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: 1rem 1.3rem; background: var(--surface); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 10; }
.brand { text-decoration: none; color: var(--text); font-weight: 700; display: inline-flex; align-items: center; gap: .55rem; }
.brand-logo { width: 34px; height: 34px; object-fit: contain; border-radius: 8px; border: 1px solid var(--border); background: #fff; }
.nav { display: flex; gap: .65rem; align-items: center; flex-wrap: wrap; justify-content: flex-end; }
.nav-group { display: inline-flex; align-items: center; gap: .65rem; flex-wrap: wrap; }
.nav .nav-btn {
  min-width: 112px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  white-space: nowrap;
}
.profile-mini { display: inline-flex; align-items: center; }
.avatar-wrap { position: relative; display: inline-flex; }
.avatar-mini { width: 34px; height: 34px; border-radius: 999px; object-fit: cover; border: 2px solid var(--border); }
.avatar-fallback { display: inline-flex; align-items: center; justify-content: center; background: var(--accent); color: #123528; font-weight: 700; }
.avatar-level { position: absolute; right: -14px; bottom: -8px; font-size: .62rem; background: var(--accent-strong); color: #fff; border-radius: 999px; padding: .12rem .35rem; border: 1px solid var(--surface); }
.container { max-width: 1140px; margin: 1.2rem auto; padding: 0 1rem 2rem; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 14px; box-shadow: var(--shadow); padding: 1rem; }
.hero h1 { margin: 0 0 .6rem; }
.hero input { width: 100%; border: 1px solid var(--border); border-radius: 10px; padding: .7rem .85rem; }
.live-topic-window {
  margin-top: .6rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface);
  max-height: 280px;
  overflow: auto;
}
.live-topic-window.hidden { display: none; }
.live-topic-item {
  display: block;
  text-decoration: none;
  color: var(--text);
  padding: .55rem .75rem;
  border-bottom: 1px solid var(--border);
}
.live-topic-item:last-child { border-bottom: 0; }
.live-topic-item small { color: var(--muted); }
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; margin: 1rem 0; }
.topic-list { display: grid; gap: .7rem; }
.topic-item { border: 1px solid var(--border); border-radius: 10px; padding: .7rem; background: var(--surface-soft); }
.topic-item p { margin: .35rem 0; color: var(--muted); }
.category-segment { margin-bottom: 1rem; }
.subcategory-grid { display: grid; gap: .8rem; }
.subcategory-card { border: 1px solid var(--border); border-radius: 12px; background: var(--surface); padding: .8rem; }
.subcategory-head { display: flex; justify-content: space-between; align-items: flex-start; gap: .8rem; }
.subcategory-head h3 { margin: 0; }
.subcategory-head p { margin: .3rem 0 0; color: var(--muted); }
.subcategory-topics { margin-top: .7rem; display: grid; gap: .6rem; }
.hidden { display: none; }
.mobile-nav-fab {
  display: none;
  position: fixed;
  right: 14px;
  bottom: 18px;
  z-index: 1200;
  border: 0;
  border-radius: 999px;
  width: 58px;
  height: 58px;
  background: var(--accent-strong);
  color: #fff;
  font-weight: 700;
  box-shadow: var(--shadow);
}
.btn { border: 0; border-radius: 10px; padding: .55rem .9rem; cursor: pointer; background: var(--accent); color: #133327; text-decoration: none; font-weight: 600; }
.btn:hover { background: var(--accent-strong); color: #ffffff; }
.btn-outline { background: transparent; border: 1px solid var(--accent); color: var(--text); }
.btn-outline:hover { background: #ecf9f2; color: #1b3f31; }
.auth-card { max-width: 430px; margin: 2rem auto; }
.auth-card form { display: grid; gap: .65rem; }
.auth-card input { width: 100%; border: 1px solid var(--border); border-radius: 10px; padding: .65rem; }
.content-html { line-height: 1.6; }
.content-html pre { background: #0f172a; color: #e2e8f0; padding: .7rem; border-radius: 8px; overflow-x: auto; }
.hl { background: #d9f5e7; color: #1f4f3b; padding: 0 .1rem; border-radius: 3px; }
.site-footer { margin-top: 1rem; padding: 1rem; text-align: center; color: var(--muted); border-top: 1px solid var(--border); background: var(--surface); }
.footer-links { display: flex; gap: .8rem; justify-content: center; flex-wrap: wrap; margin-bottom: .35rem; }
.footer-links a { color: var(--text); text-decoration: none; border-bottom: 1px solid transparent; }
.footer-links a:hover { color: var(--accent-strong); border-bottom-color: var(--accent-strong); }
.row { display: flex; gap: .6rem; flex-wrap: wrap; }
.quiz-sim select { width: 100%; border: 1px solid var(--border); border-radius: 10px; padding: .6rem; margin-top: .35rem; margin-bottom: .8rem; }
.quiz-progress { margin: .4rem 0 .8rem; color: var(--muted); font-weight: 600; }
.quiz-options { display: grid; gap: .6rem; margin: .8rem 0; }
.quiz-option { border: 1px solid var(--border); border-radius: 10px; padding: .55rem .7rem; background: var(--surface-soft); cursor: pointer; }
.quiz-option input { margin-right: .45rem; }
.quiz-results { display: grid; gap: .7rem; margin-top: .8rem; }
.profile-grid { display: grid; grid-template-columns: minmax(220px, 320px) 1fr; gap: 1rem; }
.profile-avatar-wrap { display: grid; gap: .75rem; align-content: start; }
.profile-avatar-box { position: relative; width: 220px; height: 220px; }
.profile-avatar { width: 100%; height: 100%; border-radius: 16px; object-fit: cover; border: 2px solid var(--border); background: var(--surface-soft); }
.profile-avatar-fallback { display: flex; align-items: center; justify-content: center; font-size: 3rem; font-weight: 700; color: #1a4333; background: var(--accent); }
.profile-level-badge { position: absolute; right: 10px; bottom: 10px; background: var(--accent-strong); color: #fff; border-radius: 999px; padding: .25rem .65rem; font-weight: 700; border: 2px solid var(--surface); }
.profile-form { display: grid; gap: .6rem; margin-top: .8rem; }
.profile-form input { width: 100%; border: 1px solid var(--border); border-radius: 10px; padding: .65rem; }
.videos-page { margin-top: 1rem; }
.videos-toolbar { display: grid; gap: .35rem; max-width: 360px; margin-bottom: .9rem; }
.videos-toolbar select { border: 1px solid var(--border); border-radius: 10px; padding: .6rem; background: var(--surface); color: var(--text); }
.videos-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: .9rem; }
.video-card video { width: 100%; border-radius: 10px; border: 1px solid var(--border); background: #000; max-height: 220px; }
.support-page { margin-top: 1rem; }
.support-layout { display: grid; grid-template-columns: 320px 1fr; gap: 1rem; }
.support-col { display: grid; gap: .8rem; align-content: start; }
.support-form { display: grid; gap: .55rem; }
.support-form input, .support-form select, .support-form textarea { border: 1px solid var(--border); border-radius: 10px; padding: .65rem; background: var(--surface); color: var(--text); }
.support-ticket-list { display: grid; gap: .45rem; }
.support-ticket-item { text-align: left; border: 1px solid var(--border); border-radius: 10px; background: var(--surface-soft); color: var(--text); padding: .55rem .65rem; cursor: pointer; display: grid; gap: .2rem; }
.support-ticket-item.active { border-color: var(--accent-strong); background: #edf8f2; }
.support-ticket-card { border: 1px solid var(--border); border-radius: 12px; background: var(--surface); padding: .8rem; }
.support-msg-list { display: grid; gap: .55rem; margin: .7rem 0; }
.support-msg { border: 1px solid var(--border); border-radius: 10px; padding: .55rem .65rem; background: var(--surface-soft); }
.support-msg.admin { background: #eef8f2; border-color: #cfe8dc; }
.support-msg.user { background: #f8fbff; border-color: #dce8f6; }
.support-msg p { margin: .2rem 0; }
.legal-page h2 { margin-top: 1.1rem; }
.exam-system-page { margin-top: 1rem; }
.exam-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.exam-filters { margin-bottom: .7rem; }
.exam-filters select { width: 100%; border: 1px solid var(--border); border-radius: 10px; padding: .6rem; background: var(--surface); color: var(--text); }
.exam-attempts { display: grid; gap: .65rem; }
.exam-best { display: inline-block; margin-left: .35rem; padding: .1rem .45rem; border-radius: 999px; background: #d9f5e7; color: #1d4f3a; font-size: .75rem; }
.exam-run-head { display: flex; align-items: center; gap: .7rem; justify-content: space-between; margin-bottom: .8rem; flex-wrap: wrap; }
.exam-timer { font-weight: 700; background: #ecf9f2; border: 1px solid var(--border); border-radius: 10px; padding: .35rem .6rem; }
.exam-navigator { display: flex; gap: .4rem; flex-wrap: wrap; margin-bottom: .7rem; }
.exam-nav-item { min-width: 40px; border-radius: 8px; border: 1px solid var(--border); background: var(--surface); color: var(--text); padding: .35rem .5rem; cursor: pointer; }
.exam-nav-item.open { background: #fff; }
.exam-nav-item.answered { background: #e9f8f0; border-color: #bfe4d2; }
.exam-nav-item.review { background: #fff2da; border-color: #f0d7a5; }
.exam-nav-item.current { background: var(--accent); border-color: var(--accent-strong); color: #133327; font-weight: 700; }
.exam-matching, .exam-fill, .exam-ordering { display: grid; gap: .55rem; }
.exam-matching label { display: grid; gap: .25rem; }
.exam-matching select, .exam-fill input, .exam-ordering select { width: 100%; border: 1px solid var(--border); border-radius: 10px; padding: .55rem; background: var(--surface); color: var(--text); }
.exam-popup-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(6, 14, 18, 0.72);
  display: flex;
  align-items: stretch;
  justify-content: center;
  padding: 1rem;
}
.exam-popup-shell {
  width: min(1200px, 100%);
  height: 100%;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 14px;
  overflow: auto;
  box-shadow: var(--shadow);
  padding: .8rem;
}
.exam-popup-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .7rem;
  margin-bottom: .6rem;
}
.exam-popup-content { min-height: 120px; }
body.exam-popup-open { overflow: hidden; }
.dashboard-page { margin-top: 1rem; display: grid; gap: .8rem; }
.dash-user-head { display: flex; justify-content: space-between; align-items: center; gap: .8rem; flex-wrap: wrap; }
.dash-progress { padding: .8rem; }
.dash-progressbar { height: 12px; border-radius: 999px; border: 1px solid var(--border); background: var(--surface-soft); overflow: hidden; }
.dash-progressbar i { display: block; height: 100%; background: linear-gradient(90deg, var(--accent), var(--accent-strong)); }
.dash-role-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: .7rem; }
.dash-mini { border: 1px solid var(--border); border-radius: 12px; background: var(--surface-soft); padding: .65rem; }
.dash-mini h4 { margin: 0 0 .35rem; }
.dash-mini p { margin: 0; font-size: 1.2rem; font-weight: 700; }
.dash-notify-head { display: flex; justify-content: space-between; align-items: center; gap: .6rem; flex-wrap: wrap; }
.dash-notify-list { display: grid; gap: .55rem; margin-top: .55rem; }
.dash-notify-item { border: 1px solid var(--border); border-radius: 10px; background: var(--surface-soft); padding: .55rem .65rem; cursor: pointer; }
.dash-notify-item.unread { border-color: var(--accent-strong); background: #ecfaf3; }
.dash-notify-item h4, .dash-notify-item p { margin: .15rem 0; }
.notify-badge { display: inline-flex; align-items: center; justify-content: center; min-width: 24px; height: 24px; border-radius: 999px; background: var(--accent-strong); color: #fff; padding: 0 .4rem; font-size: .8rem; vertical-align: middle; }

@media (max-width: 800px) {
  .topbar { padding: .8rem; }
  .nav {
    display: none;
    position: fixed;
    inset: 58px 0 auto 0;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: .75rem;
    max-height: calc(100vh - 70px);
    overflow: auto;
    z-index: 1100;
  }
  body.mobile-nav-open .nav { display: grid; gap: .7rem; justify-content: stretch; }
  .nav-group { display: grid; gap: .55rem; }
  .nav .nav-btn { min-width: 100px; width: 100%; }
  .mobile-nav-fab { display: inline-flex; align-items: center; justify-content: center; }
  .profile-grid { grid-template-columns: 1fr; }
  .profile-avatar-box { width: 180px; height: 180px; }
  .support-layout { grid-template-columns: 1fr; }
  .exam-grid { grid-template-columns: 1fr; }
  .exam-popup-overlay { padding: .4rem; }
  .exam-popup-shell { border-radius: 10px; padding: .55rem; }
  .dash-user-head { align-items: flex-start; }
}