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

    :root {
      --bg:       #0c0e1a;
      --surface:  #13162a;
      --surface2: #1a1d2e;
      --surface3: #22263a;
      --border:   #2a2f4a;
      --p:        #6c63ff;
      --p2:       #9d97ff;
      --green:    #06d6a0;
      --red:      #ff6b6b;
      --yellow:   #ffd166;
      --blue:     #4cc9f0;
      --orange:   #ff9f43;
      --text:     #eef0ff;
      --muted:    #6b7299;
      --r:        14px;
    }

    html { scroll-behavior: smooth; }

    body {
      font-family: 'Inter', sans-serif;
      background: var(--bg);
      color: var(--text);
      min-height: 100vh;
      overflow-x: hidden;
    }

    /* ─── SCROLLBAR ─── */
    ::-webkit-scrollbar { width: 6px; }
    ::-webkit-scrollbar-track { background: var(--bg); }
    ::-webkit-scrollbar-thumb { background: var(--border); border-radius: 99px; }

    /* ════════════════════════════════════════
       TOP NAV
    ════════════════════════════════════════ */
    .top-nav {
      position: fixed; top: 0; left: 0; right: 0; z-index: 200;
      background: rgba(12,14,26,.85);
      backdrop-filter: blur(18px);
      border-bottom: 1px solid var(--border);
      display: flex; align-items: center; justify-content: space-between;
      padding: 0 28px; height: 60px;
    }
    .nav-logo {
      display: flex; align-items: center; gap: 10px;
      font-weight: 800; font-size: .95rem; color: var(--text);
      text-decoration: none;
    }
    .nav-logo img.es-nav-icon {
      width: 36px; height: 36px; border-radius: 50%;
      object-fit: cover; display: block;
    }
    .nav-logo-text {
      display: flex; flex-direction: column; line-height: 1.1;
    }
    .nav-logo-text .nl-name {
      font-size: .82rem; font-weight: 800; color: var(--text); letter-spacing: .02em;
    }
    .nav-logo-text .nl-tagline {
      font-size: .62rem; color: var(--muted); font-weight: 500; letter-spacing: .04em;
    }
    @media (max-width: 480px) { .nav-logo-text .nl-tagline { display: none; } }
    .nav-tabs {
      display: flex; gap: 4px;
    }
    .nav-tab {
      padding: 7px 16px; border-radius: 50px;
      font-size: .78rem; font-weight: 600;
      color: var(--muted); cursor: pointer;
      border: none; background: transparent;
      transition: all .2s; white-space: nowrap;
    }
    .nav-tab:hover { color: var(--text); background: var(--surface3); }
    .nav-tab.active { background: var(--p); color: #fff; }
    .nav-preply {
      display: flex; align-items: center; gap: 7px;
      padding: 8px 18px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, #7c3aed, var(--p));
      color: #fff; font-size: .78rem; font-weight: 700;
      cursor: pointer; text-decoration: none;
      transition: opacity .2s, transform .15s; white-space: nowrap;
    }
    .nav-preply:hover { opacity: .88; transform: scale(1.03); }
    @media (max-width: 680px) {
      .nav-tabs { display: none; }
      .nav-preply span { display: none; }
    }

    /* ════════════════════════════════════════
       HERO
    ════════════════════════════════════════ */
    .hero {
      min-height: 100vh;
      display: flex; flex-direction: column;
      align-items: center; justify-content: center;
      text-align: center;
      padding: 100px 24px 80px;
      position: relative; overflow: hidden;
    }
    .hero-bg {
      position: absolute; inset: 0; pointer-events: none; z-index: 0;
    }
    .orb {
      position: absolute; border-radius: 50%; filter: blur(100px); opacity: .25;
      animation: orbFloat 10s ease-in-out infinite alternate;
    }
    .orb1 { width: 520px; height: 520px; background: var(--p);  top: -160px; left: -100px; animation-duration: 12s; }
    .orb2 { width: 400px; height: 400px; background: var(--green); bottom: -120px; right: -80px; animation-duration: 9s; animation-delay: -3s; }
    .orb3 { width: 300px; height: 300px; background: var(--blue); top: 40%; left: 55%; animation-duration: 14s; animation-delay: -6s; }
    @keyframes orbFloat {
      from { transform: translate(0,0) scale(1); }
      to   { transform: translate(30px,40px) scale(1.08); }
    }
    .hero-inner { position: relative; z-index: 1; max-width: 760px; }
    .hero-badge {
      display: inline-flex; align-items: center; gap: 8px;
      background: rgba(108,99,255,.15);
      border: 1px solid rgba(108,99,255,.35);
      border-radius: 50px; padding: 7px 20px;
      font-size: .72rem; font-weight: 700; color: var(--p2);
      letter-spacing: .1em; text-transform: uppercase; margin-bottom: 24px;
    }
    .hero h1 {
      font-size: clamp(2.4rem, 5.5vw, 4rem);
      font-weight: 850; 
      line-height: 1.08; 
      margin-bottom: 20px;
      letter-spacing: -.035em;
    }
    .hero h1 .line-accent {
      background: linear-gradient(135deg, var(--p2) 0%, var(--green) 100%);
      -webkit-background-clip: text; -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-sub {
      font-size: 1.08rem; color: var(--muted); line-height: 1.7;
      max-width: 560px; margin: 0 auto 40px;
    }
    .hero-sub strong { color: var(--text); }

    .kit-pills {
      display: flex; flex-wrap: wrap; gap: 12px;
      justify-content: center; margin-bottom: 44px;
    }
    .kit-pill {
      display: flex; align-items: center; gap: 9px;
      background: var(--surface2);
      border: 1px solid var(--border);
      border-radius: 50px; padding: 10px 20px;
      font-size: .82rem; font-weight: 600;
      transition: border-color .2s, transform .2s;
      cursor: pointer; text-decoration: none; color: var(--text);
    }
    .kit-pill:hover { border-color: var(--p2); transform: translateY(-2px); }
    .kit-pill i { font-size: .9rem; }
    .pill-slides  i { color: var(--yellow); }
    .pill-audio   i { color: var(--green); }
    .pill-quiz    i { color: var(--p2); }

    .hero-ctas {
      display: flex; gap: 14px; flex-wrap: wrap; justify-content: center;
      margin-bottom: 52px;
    }
    .hero-btn-main {
      display: inline-flex; align-items: center; gap: 10px;
      padding: 17px 40px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, var(--p), var(--p2));
      color: #fff; font-size: 1rem; font-weight: 800;
      cursor: pointer; text-decoration: none;
      box-shadow: 0 8px 36px rgba(108,99,255,.4);
      transition: transform .18s, box-shadow .18s;
    }
    .hero-btn-main:hover { transform: translateY(-2px); box-shadow: 0 14px 44px rgba(108,99,255,.55); }
    .hero-btn-ghost {
      display: inline-flex; align-items: center; gap: 10px;
      padding: 16px 32px; border-radius: 50px;
      border: 1px solid var(--border);
      background: transparent; color: var(--text);
      font-size: .95rem; font-weight: 700;
      cursor: pointer; text-decoration: none;
      transition: border-color .2s, background .2s;
    }
    .hero-btn-ghost:hover { border-color: var(--p2); background: rgba(108,99,255,.08); }

    .hero-proof {
      display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
      justify-content: center;
    }
    .proof-avatars {
      display: flex;
    }
    .proof-avatars span {
      width: 34px; height: 34px; border-radius: 50%;
      border: 2px solid var(--bg);
      display: flex; align-items: center; justify-content: center;
      font-size: .75rem; font-weight: 700; color: #fff;
      margin-left: -10px;
    }
    .proof-avatars span:first-child { margin-left: 0; }
    .proof-text { font-size: .82rem; color: var(--muted); }
    .proof-text strong { color: var(--text); }
    .proof-stars { color: var(--yellow); font-size: .78rem; letter-spacing: .06em; }

    .scroll-hint {
      position: absolute; bottom: 32px; left: 50%;
      transform: translateX(-50%);
      display: flex; flex-direction: column; align-items: center;
      gap: 6px; color: var(--muted); font-size: .7rem;
      font-weight: 600; letter-spacing: .08em; text-transform: uppercase;
      animation: bounce 2s ease-in-out infinite;
      z-index: 1;
    }
    @keyframes bounce {
      0%,100% { transform: translateX(-50%) translateY(0); }
      50%      { transform: translateX(-50%) translateY(7px); }
    }

    .section-nav {
      position: sticky; top: 60px; z-index: 100;
      background: rgba(12,14,26,.92);
      backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--border);
    }
    .section-nav-inner {
      max-width: 960px; margin: 0 auto;
      display: flex; overflow-x: auto; gap: 0;
      scrollbar-width: none;
    }
    .section-nav-inner::-webkit-scrollbar { display: none; }
    .snav-btn {
      display: flex; align-items: center; gap: 9px;
      padding: 16px 28px; border: none; background: none;
      color: var(--muted); font-size: .82rem; font-weight: 600;
      cursor: pointer; white-space: nowrap;
      border-bottom: 2px solid transparent;
      transition: color .2s, border-color .2s;
      position: relative;
    }
    .snav-btn:hover { color: var(--text); }
    .snav-btn.active { color: #fff; border-bottom-color: var(--p); }
    .snav-btn .snav-icon {
      width: 26px; height: 26px; border-radius: 7px;
      display: flex; align-items: center; justify-content: center;
      font-size: .72rem; flex-shrink: 0;
    }
    .snav-btn:nth-child(1) .snav-icon { background: rgba(255,209,102,.15); color: var(--yellow); }
    .snav-btn:nth-child(2) .snav-icon { background: rgba(6,214,160,.12);   color: var(--green); }
    .snav-btn:nth-child(3) .snav-icon { background: rgba(108,99,255,.15);  color: var(--p2); }
    .snav-btn.active:nth-child(1) { color: var(--yellow); border-bottom-color: var(--yellow); }
    .snav-btn.active:nth-child(2) { color: var(--green);  border-bottom-color: var(--green); }
    .snav-btn.active:nth-child(3) { color: var(--p2);     border-bottom-color: var(--p2); }

    .kit-section {
      max-width: 960px; margin: 0 auto;
      padding: 72px 24px;
    }
    .section-head {
      display: flex; align-items: center;
      justify-content: space-between; gap: 20px;
      margin-bottom: 40px; flex-wrap: wrap;
    }
    .section-label {
      display: inline-flex; align-items: center; gap: 8px;
      border-radius: 50px; padding: 5px 14px;
      font-size: .68rem; font-weight: 700;
      text-transform: uppercase; letter-spacing: .09em;
      margin-bottom: 10px;
    }
    .section-head h2 {
      font-size: clamp(1.5rem, 3vw, 2.1rem);
      font-weight: 800; line-height: 1.2;
    }
    .section-head p { color: var(--muted); font-size: .9rem; line-height: 1.6; margin-top: 8px; max-width: 480px; }
    .section-divider {
      border: none; border-top: 1px solid var(--border);
    }

    #slides .section-label  { background: rgba(255,209,102,.12); color: var(--yellow); border: 1px solid rgba(255,209,102,.2); }

    .slides-viewer {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: 20px;
      overflow: hidden;
    }
    .slides-stage {
      position: relative;
      aspect-ratio: 16/9;
      background: var(--surface2);
      overflow: hidden;
      user-select: none;
    }
    .slide {
      position: absolute; inset: 0;
      display: flex; flex-direction: column;
      align-items: center; justify-content: center;
      padding: clamp(24px, 5%, 64px);
      text-align: center;
      opacity: 0; transform: translateX(40px);
      transition: opacity .38s ease, transform .38s ease;
      pointer-events: none;
    }
    .slide.active {
      opacity: 1; transform: translateX(0);
      pointer-events: auto;
    }
    .slide.exit {
      opacity: 0; transform: translateX(-40px);
    }
    .slide-cover {
      background: linear-gradient(135deg, #0f0c29, #1a1242, #0f1117);
    }
    .slide-cover::before {
      content: '';
      position: absolute; inset: 0;
      background: radial-gradient(ellipse 80% 70% at 50% 40%, rgba(108,99,255,.28) 0%, transparent 65%);
    }
    .slide-cover .cover-tag {
      display: inline-flex; align-items: center; gap: 7px;
      background: rgba(108,99,255,.2); border: 1px solid rgba(108,99,255,.4);
      border-radius: 50px; padding: 6px 16px;
      font-size: .7rem; font-weight: 700; color: var(--p2);
      letter-spacing: .1em; text-transform: uppercase;
      margin-bottom: 20px; position: relative; z-index: 1;
    }
    .slide-cover h2 {
      font-size: clamp(1.6rem, 4.5vw, 3.2rem);
      font-weight: 900; line-height: 1.1;
      background: linear-gradient(135deg, #fff 40%, var(--p2));
      -webkit-background-clip: text; -webkit-text-fill-color: transparent;
      background-clip: text; margin-bottom: 14px;
      position: relative; z-index: 1;
    }
    .slide-cover p {
      color: var(--muted); font-size: clamp(.78rem, 2vw, .98rem);
      position: relative; z-index: 1; max-width: 440px;
    }
    .slide-cat {
      align-items: flex-start; text-align: left;
      padding: clamp(20px, 4%, 52px);
    }
    .slide-cat-header {
      display: flex; align-items: center; gap: 12px;
      margin-bottom: clamp(14px, 3%, 28px);
    }
    .slide-cat-icon {
      width: clamp(38px,6vw,52px); height: clamp(38px,6vw,52px);
      border-radius: clamp(10px,2vw,14px);
      display: flex; align-items: center; justify-content: center;
      font-size: clamp(.9rem,2vw,1.3rem); flex-shrink: 0;
    }
    .slide-cat-title {
      font-size: clamp(.7rem, 1.6vw, .9rem);
      font-weight: 700; text-transform: uppercase;
      letter-spacing: .07em; opacity: .7;
    }
    .slide-cat h3 {
      font-size: clamp(1.1rem, 3vw, 1.9rem);
      font-weight: 800; margin-bottom: clamp(14px, 3%, 26px);
      line-height: 1.15;
    }
    .slide-words-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(clamp(130px,22%,200px), 1fr));
      gap: clamp(7px, 1.5%, 14px);
      width: 100%;
    }
    .slide-word-chip {
      background: rgba(255,255,255,.05);
      border: 1px solid rgba(255,255,255,.08);
      border-radius: clamp(8px,1.5vw,12px);
      padding: clamp(8px,1.5%,14px) clamp(10px,2%,18px);
    }
    .swc-word {
      font-size: clamp(.75rem, 1.8vw, .95rem);
      font-weight: 700; margin-bottom: 3px; color: #fff;
    }
    .swc-def {
      font-size: clamp(.6rem, 1.3vw, .72rem);
      color: var(--muted); line-height: 1.4;
    }
    .slides-controls {
      display: flex; align-items: center; justify-content: space-between;
      padding: 14px 20px;
      border-top: 1px solid var(--border);
      background: var(--surface);
    }
    .slide-nav-btn {
      width: 38px; height: 38px; border-radius: 50%;
      border: 1px solid var(--border); background: var(--surface2);
      color: var(--text); font-size: .85rem; cursor: pointer;
      display: flex; align-items: center; justify-content: center;
      transition: all .18s;
    }
    .slide-nav-btn:hover:not(:disabled) { border-color: var(--p2); background: rgba(108,99,255,.12); }
    .slide-nav-btn:disabled { opacity: .3; cursor: default; }
    .slide-dots {
      display: flex; gap: 7px; align-items: center;
    }
    .slide-dot {
      width: 7px; height: 7px; border-radius: 50%;
      background: var(--border); cursor: pointer;
      transition: background .2s, transform .2s;
    }
    .slide-dot.active { background: var(--yellow); transform: scale(1.35); }
    .slide-counter {
      font-size: .75rem; color: var(--muted); font-weight: 600;
      min-width: 52px; text-align: right;
    }

    #audio .section-label { background: rgba(6,214,160,.1); color: var(--green); border: 1px solid rgba(6,214,160,.2); }

    .audio-toolbar {
      display: flex; align-items: center;
      justify-content: space-between;
      flex-wrap: wrap; gap: 12px;
      margin-bottom: 20px;
    }
    .audio-filter-tabs {
      display: flex; flex-wrap: wrap; gap: 7px;
    }
    .af-tab {
      padding: 6px 15px; border-radius: 50px;
      border: 1px solid var(--border); background: var(--surface2);
      color: var(--muted); font-size: .75rem; font-weight: 600;
      cursor: pointer; transition: all .18s; white-space: nowrap;
    }
    .af-tab:hover  { border-color: var(--p2); color: var(--text); }
    .af-tab.active { background: var(--p); border-color: var(--p); color: #fff; }

    .audio-right { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }

    .speed-grp { display: flex; gap: 6px; align-items: center; }
    .speed-lbl { font-size: .72rem; color: var(--muted); font-weight: 600; }
    .spd-btn {
      padding: 5px 13px; border-radius: 50px;
      border: 1px solid var(--border); background: var(--surface2);
      color: var(--muted); font-size: .72rem; font-weight: 700;
      cursor: pointer; transition: all .18s;
    }
    .spd-btn:hover { border-color: var(--green); color: var(--green); }
    .spd-btn.active { background: var(--green); border-color: var(--green); color: #000; }

    .play-all-btn {
      display: flex; align-items: center; gap: 7px;
      padding: 8px 20px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, var(--green), #00b894);
      color: #fff; font-size: .78rem; font-weight: 700;
      cursor: pointer; transition: opacity .2s, transform .15s;
      white-space: nowrap;
    }
    .play-all-btn:hover { opacity: .88; transform: scale(1.03); }

    .audio-progress-row {
      display: flex; align-items: center; gap: 12px; margin-bottom: 24px;
    }
    .ap-bar-bg {
      flex: 1; height: 5px; background: var(--surface3);
      border-radius: 99px; overflow: hidden;
    }
    .ap-bar-fill {
      height: 100%;
      background: linear-gradient(90deg, var(--p), var(--green));
      border-radius: 99px; transition: width .4s ease; width: 0%;
    }
    .ap-label { font-size: .72rem; color: var(--muted); white-space: nowrap; }

    .vocab-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
      gap: 14px;
    }
    .vcard {
      background: var(--surface);
      border: 1px solid var(--border);
      border-radius: var(--r);
      padding: 18px 18px 15px;
      display: flex; flex-direction: column; gap: 9px;
      transition: transform .18s, border-color .18s, box-shadow .18s;
      position: relative; overflow: hidden;
    }
    .vcard::before {
      content: ''; position: absolute;
      top: 0; left: 0; right: 0; height: 3px;
      border-radius: var(--r) var(--r) 0 0;
    }
    .vcard:hover { transform: translateY(-3px); box-shadow: 0 10px 28px rgba(0,0,0,.35); }
    .vcard.vc-playing { box-shadow: 0 0 0 2px rgba(108,99,255,.35), 0 10px 28px rgba(0,0,0,.4); }
    .vcard.vc-listened .vc-word::after { content: ' ✓'; color: var(--green); font-size: .82em; }
    .vc0::before { background: var(--p); }
    .vc1::before { background: var(--yellow); }
    .vc2::before { background: var(--red); }
    .vc3::before { background: var(--green); }
    .vc4::before { background: var(--blue); }
    .vc5::before { background: var(--orange); }

    .vcard.vhidden { display: none; }

    .vc-top { display: flex; justify-content: space-between; align-items: flex-start; gap: 10px; }
    .vc-left { flex: 1; min-width: 0; }
    .vc-cat  { font-size: .65rem; font-weight: 700; text-transform: uppercase; letter-spacing: .07em; margin-bottom: 4px; opacity: .75; }
    .vc-word { font-size: 1.08rem; font-weight: 700; color: #fff; }
    .vc-ipa  { font-size: .75rem; color: var(--muted); margin-top: 3px; font-style: italic; }
    .vc-def  { font-size: .78rem; color: var(--muted); line-height: 1.5; }
    .vc-ex   { font-size: .73rem; color: #484e72; border-left: 2px solid var(--border); padding-left: 9px; line-height: 1.45; font-style: italic; }

    .vc-play-btn {
      width: 42px; height: 42px; border-radius: 50%; border: none;
      display: flex; align-items: center; justify-content: center;
      font-size: .9rem; cursor: pointer; flex-shrink: 0;
      color: #fff; transition: transform .15s, opacity .15s;
    }
    .vc-play-btn:hover { transform: scale(1.1); }
    .vc-play-btn:active { transform: scale(.95); }
    .vc-play-btn.vc-speaking { animation: vcPulse 1s infinite; }
    @keyframes vcPulse { 0%,100%{box-shadow:0 0 0 0 rgba(108,99,255,.5)} 50%{box-shadow:0 0 0 8px rgba(108,99,255,0)} }
    .vc0 .vc-play-btn { background: linear-gradient(135deg, #6c63ff, #9d97ff); }
    .vc1 .vc-play-btn { background: linear-gradient(135deg, #ffd166, #ffb347); }
    .vc2 .vc-play-btn { background: linear-gradient(135deg, #ff6b6b, #ee5a24); }
    .vc3 .vc-play-btn { background: linear-gradient(135deg, #06d6a0, #00b894); }
    .vc4 .vc-play-btn { background: linear-gradient(135deg, #4cc9f0, #0096c7); }
    .vc5 .vc-play-btn { background: linear-gradient(135deg, #ff9f43, #e67e22); }

    .article-section {
      max-width: 960px;
      margin: 0 auto;
      padding: 72px 24px;
    }

    .article-card {
      position: relative;
      overflow: hidden;
      background:
        radial-gradient(circle at top right, rgba(108,99,255,.18), transparent 34%),
        linear-gradient(180deg, rgba(255,255,255,.025), transparent),
        var(--surface);
      border: 1px solid var(--border);
      border-radius: 24px;
      padding: clamp(30px, 5vw, 54px);
      box-shadow: 0 24px 70px rgba(0,0,0,.35);
    }

    .article-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 18%;
      right: 18%;
      height: 3px;
      background: linear-gradient(90deg, transparent, var(--p2), transparent);
    }

    .article-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: rgba(108,99,255,.15);
      border: 1px solid rgba(108,99,255,.38);
      border-radius: 50px;
      padding: 7px 18px;
      color: var(--p2);
      font-size: .72rem;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: .09em;
      margin-bottom: 24px;
    }

    .article-quote {
      position: absolute;
      top: 28px;
      right: 34px;
      color: rgba(157,151,255,.12);
      font-size: clamp(3rem, 8vw, 6rem);
      line-height: 1;
    }

    .article-card h2 {
      max-width: 720px;
      font-size: clamp(1.8rem, 4vw, 2.75rem);
      line-height: 1.12;
      letter-spacing: -.04em;
      margin-bottom: 24px;
      position: relative;
      z-index: 1;
    }

    .article-card p {
      max-width: 780px;
      color: var(--muted);
      font-size: 1rem;
      line-height: 1.85;
      margin-bottom: 20px;
      position: relative;
      z-index: 1;
    }

    .article-card strong {
      color: var(--text);
      font-weight: 800;
    }

    .article-card em {
      color: var(--p2);
      font-style: italic;
    }

    .article-pill-row {
      display: flex;
      flex-wrap: wrap;
      gap: 9px;
      margin: 26px 0;
      position: relative;
      z-index: 1;
    }

    .article-pill-row span {
      display: inline-flex;
      align-items: center;
      border: 1px solid rgba(157,151,255,.35);
      background: rgba(108,99,255,.12);
      color: var(--p2);
      padding: 7px 14px;
      border-radius: 999px;
      font-size: .75rem;
      font-weight: 800;
    }

    .article-cta {
      display: inline-flex;
      align-items: center;
      gap: 9px;
      margin-top: 18px;
      padding: 15px 30px;
      border-radius: 999px;
      background: linear-gradient(135deg, var(--p), var(--p2));
      color: #fff;
      text-decoration: none;
      font-size: .92rem;
      font-weight: 850;
      box-shadow: 0 8px 34px rgba(108,99,255,.38);
      transition: transform .18s, box-shadow .18s;
      position: relative;
      z-index: 1;
    }

    .article-cta:hover {
      transform: translateY(-2px);
      box-shadow: 0 14px 44px rgba(108,99,255,.52);
    }

    @media (max-width: 640px) {
      .article-section {
        padding: 54px 18px;
      }

      .article-quote {
        display: none;
      }

      .article-card p {
        font-size: .94rem;
      }
    }

    #quiz .section-label { background: rgba(108,99,255,.12); color: var(--p2); border: 1px solid rgba(108,99,255,.2); }

    .qscreen { display: none; }
    .qscreen.qactive { display: block; }

    .quiz-start-panel {
      background: var(--surface); border: 1px solid var(--border);
      border-radius: 20px; padding: 36px 32px;
    }
    .quiz-mode-grid {
      display: grid; grid-template-columns: repeat(auto-fill, minmax(190px,1fr));
      gap: 12px; margin-bottom: 28px;
    }
    .qmode-card {
      background: var(--surface2); border: 2px solid var(--border);
      border-radius: 14px; padding: 18px 16px;
      cursor: pointer; transition: border-color .18s, transform .18s, box-shadow .18s;
      position: relative; overflow: hidden;
    }
    .qmode-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px; }
    .qmode-card:hover { transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,.3); }
    .qmode-card.qselected { border-color: var(--p); box-shadow: 0 0 0 3px rgba(108,99,255,.18); }
    .qmode-card.qselected::after {
      content: '\f058'; font-family: 'Font Awesome 6 Free'; font-weight: 900;
      position: absolute; top: 12px; right: 14px;
      color: var(--p); font-size: 1rem;
    }
    .qmode-card:nth-child(1)::before { background: var(--p); }
    .qmode-card:nth-child(2)::before { background: var(--blue); }
    .qmode-card:nth-child(3)::before { background: var(--green); }
    .qmode-card:nth-child(4)::before { background: var(--orange); }
    .qmode-icon {
      width: 38px; height: 38px; border-radius: 10px;
      display: flex; align-items: center; justify-content: center;
      font-size: 1rem; margin-bottom: 12px;
    }
    .qmode-card:nth-child(1) .qmode-icon { background: rgba(108,99,255,.15); color: var(--p2); }
    .qmode-card:nth-child(2) .qmode-icon { background: rgba(76,201,240,.12); color: var(--blue); }
    .qmode-card:nth-child(3) .qmode-icon { background: rgba(6,214,160,.1);   color: var(--green); }
    .qmode-card:nth-child(4) .qmode-icon { background: rgba(255,159,67,.1);  color: var(--orange); }
    .qmode-card h4 { font-size: .88rem; font-weight: 700; margin-bottom: 5px; }
    .qmode-card p  { font-size: .74rem; color: var(--muted); line-height: 1.45; }

    .diff-row {
      display: flex; gap: 9px; margin-bottom: 28px; flex-wrap: wrap;
    }
    .qdiff-btn {
      padding: 8px 20px; border-radius: 50px;
      border: 1px solid var(--border); background: var(--surface2);
      color: var(--muted); font-size: .78rem; font-weight: 700;
      cursor: pointer; transition: all .18s;
    }
    .qdiff-btn:hover { color: var(--text); border-color: var(--text); }
    .qdiff-btn.qd-active { color: #000; }
    .qdiff-btn[data-d="easy"].qd-active   { background: var(--green);  border-color: var(--green); }
    .qdiff-btn[data-d="medium"].qd-active { background: var(--yellow); border-color: var(--yellow); }
    .qdiff-btn[data-d="hard"].qd-active   { background: var(--red);    border-color: var(--red); }

    .quiz-launch-btn {
      padding: 15px 44px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, var(--p), var(--p2));
      color: #fff; font-size: .98rem; font-weight: 800;
      cursor: pointer; transition: opacity .2s, transform .15s;
      display: inline-flex; align-items: center; gap: 9px;
      box-shadow: 0 6px 28px rgba(108,99,255,.38);
    }
    .quiz-launch-btn:hover { opacity: .88; transform: scale(1.03); }

    .quiz-active-panel {
      background: var(--surface); border: 1px solid var(--border);
      border-radius: 20px; overflow: hidden;
    }
    .quiz-hud {
      display: flex; align-items: center;
      justify-content: space-between;
      padding: 14px 22px; border-bottom: 1px solid var(--border);
      flex-wrap: wrap; gap: 10px;
    }
    .hud-left { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; }
    .hud-counter { font-size: .82rem; font-weight: 700; color: var(--muted); }
    .hud-counter strong { color: var(--text); font-size: .95rem; }
    .quit-quiz-btn {
      background: rgba(255,107,107,.15);
      border: 1px solid var(--red);
      color: var(--red);
      padding: 6px 16px;
      border-radius: 50px;
      font-size: .75rem;
      font-weight: 700;
      cursor: pointer;
      transition: all 0.2s;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    .quit-quiz-btn:hover { background: var(--red); color: #fff; border-color: var(--red); }
    .hud-pills { display: flex; gap: 8px; }
    .hud-pill {
      display: flex; align-items: center; gap: 5px;
      padding: 4px 13px; border-radius: 50px;
      font-size: .75rem; font-weight: 700;
    }
    .hud-correct { background: rgba(6,214,160,.12);  color: var(--green); }
    .hud-wrong   { background: rgba(255,107,107,.12); color: var(--red); }

    .hud-timer { position: relative; width: 40px; height: 40px; }
    .hud-timer svg { transform: rotate(-90deg); }
    .tr-bg   { stroke: var(--surface3); stroke-width: 4; fill: none; }
    .tr-fill {
      stroke: var(--green); stroke-width: 4; fill: none;
      stroke-linecap: round; stroke-dasharray: 110; stroke-dashoffset: 0;
      transition: stroke-dashoffset .9s linear, stroke .3s;
    }
    .tr-num {
      position: absolute; inset: 0;
      display: flex; align-items: center; justify-content: center;
      font-size: .72rem; font-weight: 800;
    }
    .hud-timer.tw .tr-fill { stroke: var(--yellow); }
    .hud-timer.td .tr-fill { stroke: var(--red); }

    .quiz-q-bar { height: 3px; background: var(--surface2); }
    .quiz-q-fill {
      height: 100%;
      background: linear-gradient(90deg, var(--p), var(--green));
      transition: width .4s ease;
    }
    .quiz-body {
      padding: 32px 28px 28px;
      display: flex; flex-direction: column; align-items: center;
    }
    .q-badge {
      display: inline-flex; align-items: center; gap: 6px;
      padding: 5px 13px; border-radius: 50px;
      font-size: .67rem; font-weight: 700;
      text-transform: uppercase; letter-spacing: .07em;
      margin-bottom: 18px;
    }
    .q-headline {
      font-size: clamp(.98rem, 2.4vw, 1.22rem);
      font-weight: 600; line-height: 1.55;
      text-align: center; margin-bottom: 8px;
      max-width: 580px;
    }
    .q-sub {
      font-size: .8rem; color: var(--muted);
      text-align: center; margin-bottom: 26px;
      font-style: italic; max-width: 520px;
    }
    .blank-span {
      display: inline-block;
      border-bottom: 3px solid var(--p);
      min-width: 110px; padding: 0 5px;
      color: var(--p); font-weight: 800;
    }
    .q-options {
      display: grid; grid-template-columns: 1fr 1fr;
      gap: 10px; width: 100%; max-width: 540px; margin-bottom: 22px;
    }
    @media (max-width: 460px) { .q-options { grid-template-columns: 1fr; } }
    .q-opt {
      padding: 14px 16px; border-radius: 12px;
      border: 2px solid var(--border); background: var(--surface2);
      color: var(--text); font-size: .85rem; font-weight: 600;
      cursor: pointer; text-align: left; line-height: 1.4;
      transition: border-color .14s, background .14s, transform .1s;
    }
    .q-opt:hover:not(:disabled) { border-color: var(--p); background: rgba(108,99,255,.1); transform: translateY(-1px); }
    .q-opt.qo-correct { border-color: var(--green) !important; background: rgba(6,214,160,.1) !important; color: var(--green) !important; }
    .q-opt.qo-wrong   { border-color: var(--red) !important;   background: rgba(255,107,107,.08) !important; color: var(--red) !important; }
    .q-opt:disabled   { cursor: default; transform: none; }
    .q-opt .ol { display: inline-flex; align-items: center; justify-content: center; width: 24px; height: 24px; border-radius: 7px; background: var(--surface3); font-size: .7rem; font-weight: 800; margin-right: 8px; vertical-align: middle; transition: background .14s; }
    .q-opt.qo-correct .ol { background: rgba(6,214,160,.22); }
    .q-opt.qo-wrong   .ol { background: rgba(255,107,107,.18); }

    .type-wrap {
      display: flex; flex-direction: column; align-items: center;
      gap: 12px; width: 100%; max-width: 400px; margin-bottom: 20px;
    }
    .type-inp {
      width: 100%; padding: 14px 18px; border-radius: 12px;
      border: 2px solid var(--border); background: var(--surface2);
      color: var(--text); font-size: .95rem; font-weight: 600;
      font-family: 'Inter', sans-serif; outline: none; text-align: center;
      transition: border-color .18s;
    }
    .type-inp:focus { border-color: var(--p); }
    .type-inp.ti-correct { border-color: var(--green); background: rgba(6,214,160,.08); color: var(--green); }
    .type-inp.ti-wrong   { border-color: var(--red);   background: rgba(255,107,107,.06); color: var(--red); }
    .type-sub-btn {
      padding: 11px 32px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, var(--p), var(--p2));
      color: #fff; font-size: .86rem; font-weight: 700;
      cursor: pointer; transition: opacity .18s, transform .14s;
    }
    .type-sub-btn:hover { opacity: .88; transform: scale(1.03); }
    .type-sub-btn:disabled { opacity: .38; cursor: default; transform: none; }

    .q-feedback {
      width: 100%; max-width: 540px;
      border-radius: 12px; padding: 14px 18px;
      display: none; align-items: flex-start; gap: 12px;
      margin-bottom: 18px;
    }
    .q-feedback.qf-show { display: flex; }
    .q-feedback.qf-ok  { background: rgba(6,214,160,.09); border: 1px solid rgba(6,214,160,.25); }
    .q-feedback.qf-bad { background: rgba(255,107,107,.07); border: 1px solid rgba(255,107,107,.2); }
    .qf-icon { font-size: 1.15rem; flex-shrink: 0; margin-top: 1px; }
    .q-feedback.qf-ok .qf-icon  { color: var(--green); }
    .q-feedback.qf-bad .qf-icon { color: var(--red); }
    .qf-title { font-size: .84rem; font-weight: 700; margin-bottom: 3px; }
    .q-feedback.qf-ok .qf-title  { color: var(--green); }
    .q-feedback.qf-bad .qf-title { color: var(--red); }
    .qf-detail { font-size: .77rem; color: var(--muted); line-height: 1.5; }
    .qf-ans { color: var(--text); font-weight: 600; }

    .q-next-btn {
      padding: 12px 36px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, var(--p), var(--p2));
      color: #fff; font-size: .88rem; font-weight: 700;
      cursor: pointer; display: none; align-items: center; gap: 8px;
      transition: opacity .18s, transform .14s;
    }
    .q-next-btn.qnshow { display: inline-flex; }
    .q-next-btn:hover { opacity: .88; transform: scale(1.03); }

    .quiz-results-panel {
      background: var(--surface); border: 1px solid var(--border);
      border-radius: 20px; padding: 44px 32px;
      display: flex; flex-direction: column; align-items: center;
    }
    .qr-ring { position: relative; width: 140px; height: 140px; margin-bottom: 22px; }
    .qr-ring svg { transform: rotate(-90deg); }
    .qrr-bg   { stroke: var(--surface3); stroke-width: 9; fill: none; }
    .qrr-fill {
      stroke: var(--green); stroke-width: 9; fill: none;
      stroke-linecap: round; stroke-dasharray: 380;
      stroke-dashoffset: 380;
      transition: stroke-dashoffset 1.1s cubic-bezier(.4,0,.2,1) .3s;
    }
    .qr-inner {
      position: absolute; inset: 0;
      display: flex; flex-direction: column;
      align-items: center; justify-content: center;
    }
    .qr-pct  { font-size: 1.9rem; font-weight: 800; }
    .qr-lbl  { font-size: .65rem; color: var(--muted); font-weight: 600; text-transform: uppercase; letter-spacing: .06em; }
    .qr-grade { font-size: 1.4rem; font-weight: 800; margin-bottom: 6px; }
    .qr-sub   { font-size: .88rem; color: var(--muted); margin-bottom: 28px; text-align: center; }
    .qr-stats { display: flex; gap: 14px; flex-wrap: wrap; justify-content: center; margin-bottom: 28px; width: 100%; max-width: 480px; }
    .qrs {
      flex: 1; min-width: 90px;
      background: var(--surface2); border: 1px solid var(--border);
      border-radius: 12px; padding: 14px 12px; text-align: center;
    }
    .qrs-n { font-size: 1.5rem; font-weight: 800; margin-bottom: 3px; }
    .qrs-l { font-size: .65rem; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
    .qrs-c { color: var(--green); } .qrs-w { color: var(--red); }
    .qrs-s { color: var(--yellow); } .qrs-t { color: var(--blue); }

    .qr-bd-title {
      font-size: .75rem; font-weight: 700; color: var(--muted);
      text-transform: uppercase; letter-spacing: .07em;
      margin-bottom: 12px; align-self: flex-start; width: 100%; max-width: 500px;
    }
    .qr-bd-list {
      width: 100%; max-width: 500px;
      display: flex; flex-direction: column; gap: 7px;
      margin-bottom: 28px;
    }
    .qr-bd-item {
      display: flex; align-items: center; gap: 10px;
      background: var(--surface2); border: 1px solid var(--border);
      border-radius: 10px; padding: 10px 14px;
    }
    .qr-bd-item.bdc { border-color: rgba(6,214,160,.22); }
    .qr-bd-item.bdw { border-color: rgba(255,107,107,.18); }
    .qr-bd-ic { font-size: .88rem; width: 20px; text-align: center; }
    .bdc .qr-bd-ic { color: var(--green); }
    .bdw .qr-bd-ic { color: var(--red); }
    .qr-bd-word { font-weight: 700; font-size: .86rem; flex: 1; }
    .qr-bd-type { font-size: .68rem; color: var(--muted); }

    .qr-btns { display: flex; gap: 11px; flex-wrap: wrap; justify-content: center; }
    .qr-retry {
      padding: 12px 28px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, var(--p), var(--p2));
      color: #fff; font-size: .88rem; font-weight: 700;
      cursor: pointer; display: flex; align-items: center; gap: 8px;
      transition: opacity .18s, transform .14s;
    }
    .qr-retry:hover { opacity: .88; transform: scale(1.03); }
    .qr-back-audio {
      padding: 11px 22px; border-radius: 50px;
      border: 1px solid var(--border); background: var(--surface2);
      color: var(--text); font-size: .82rem; font-weight: 600;
      cursor: pointer; display: flex; align-items: center; gap: 8px;
      transition: border-color .18s;
    }
    .qr-back-audio:hover { border-color: var(--green); }

    .preply-banner {
      display: none;
      max-width: 960px; margin: 0 auto 72px;
      padding: 0 24px;
    }
    .preply-banner.pb-show { display: block; }
    .pb-inner {
      background: linear-gradient(135deg, #1e1b4b 0%, #171a2e 55%, #0e1a24 100%);
      border: 1px solid rgba(108,99,255,.38);
      box-shadow: 0 0 0 1px rgba(108,99,255,.08), 0 24px 60px rgba(0,0,0,.45);
      border-radius: 22px; padding: 40px 36px;
      position: relative; overflow: hidden;
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 32px; align-items: center;
    }
    @media (max-width: 640px) {
      .pb-inner { grid-template-columns: 1fr; text-align: center; }
      .pb-right { align-items: center; }
    }
    .pb-inner::before {
      content: '';
      position: absolute; inset: 0;
      background: radial-gradient(ellipse 70% 80% at 0% 50%, rgba(108,99,255,.18) 0%, transparent 65%);
      pointer-events: none;
    }
    .pb-left { position: relative; z-index: 1; }
    .pb-tag {
      display: inline-flex; align-items: center; gap: 7px;
      background: rgba(255,255,255,.07); border: 1px solid rgba(255,255,255,.12);
      border-radius: 50px; padding: 5px 14px;
      font-size: .65rem; font-weight: 700; color: #c4b5fd;
      letter-spacing: .09em; text-transform: uppercase;
      margin-bottom: 14px;
    }
    .pb-headline {
      font-size: clamp(1.2rem, 2.8vw, 1.7rem);
      font-weight: 800; line-height: 1.2; margin-bottom: 12px;
      background: linear-gradient(135deg, #fff 40%, #c4b5fd);
      -webkit-background-clip: text; -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .pb-body {
      font-size: .85rem; color: #8f96bb; line-height: 1.65; margin-bottom: 20px;
      max-width: 520px;
    }
    .pb-body strong { color: #ddd5ff; }
    .pb-feats { display: flex; flex-wrap: wrap; gap: 8px; }
    .pb-feat {
      display: flex; align-items: center; gap: 7px;
      background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.08);
      border-radius: 50px; padding: 6px 13px;
      font-size: .74rem; font-weight: 600; color: #c4b5fd;
    }
    .pb-right {
      display: flex; flex-direction: column; align-items: flex-end;
      gap: 14px; position: relative; z-index: 1;
    }
    .pb-cta {
      display: inline-flex; align-items: center; gap: 9px;
      padding: 15px 32px; border-radius: 50px; border: none;
      background: linear-gradient(135deg, #7c3aed, #6c63ff, #a78bfa);
      color: #fff; font-size: .92rem; font-weight: 800;
      text-decoration: none; white-space: nowrap;
      box-shadow: 0 8px 32px rgba(108,99,255,.45);
      transition: transform .2s, box-shadow .2s;
    }
    .pb-cta:hover { transform: translateY(-2px) scale(1.03); box-shadow: 0 14px 40px rgba(108,99,255,.6); }
    .pb-nudge { font-size: .7rem; color: #4d5278; text-align: center; }
    .pb-nudge a { color: #9d97ff; text-decoration: none; }
    .pb-nudge a:hover { text-decoration: underline; }

    footer {
      border-top: 1px solid var(--border);
      padding: 40px 24px 32px;
      text-align: center;
      color: var(--muted); font-size: .78rem;
    }
    footer a { color: var(--p2); text-decoration: none; }
    footer a:hover { text-decoration: underline; }
    .footer-brand {
      display: flex; flex-direction: column; align-items: center; gap: 12px;
      margin-bottom: 24px;
    }
    .footer-brand img {
      width: min(320px, 80%); opacity: .85;
      transition: opacity .2s;
    }
    .footer-brand img:hover { opacity: 1; }
    .footer-divider {
      width: 48px; height: 1px; background: var(--border); margin: 0 auto 20px;
    }
    .footer-links {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 14px;
      flex-wrap: wrap;
      margin: 26px 0 18px;
    }

    .footer-links a {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      min-height: 38px;
      padding: 0 18px;
      border-radius: 999px;
      border: 1px solid var(--border);
      background: var(--surface2);
      color: var(--text);
      text-decoration: none;
      font-size: .88rem;
      font-weight: 800;
      transition: all .18s ease;
    }

    .footer-links a:hover {
      color: #fff;
      border-color: var(--p2);
      background: rgba(108,99,255,.12);
      transform: translateY(-2px);
      text-decoration: none;
    }

    #toast {
      position: fixed; bottom: 28px; left: 50%;
      transform: translateX(-50%) translateY(80px);
      background: var(--surface3); border: 1px solid var(--border);
      color: var(--text); padding: 11px 22px; border-radius: 50px;
      font-size: .8rem; font-weight: 500;
      transition: transform .35s cubic-bezier(.34,1.56,.64,1);
      z-index: 999; pointer-events: none; white-space: nowrap;
    }
    #toast.show { transform: translateX(-50%) translateY(0); }

    #confetti {
      position: fixed; inset: 0;
      pointer-events: none; z-index: 9999;
    }

/* Local lightweight icon fallback replacing Font Awesome webfont dependency. */
.fas, .fa {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.15em;
  min-width: 1.15em;
  height: 1.15em;
  margin-right: .35em;
  font-style: normal;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-weight: 800;
  line-height: 1;
  vertical-align: -0.08em;
}
.fas::before, .fa::before { content: "•"; }
.fa-home::before { content: "⌂"; }
.fa-layer-group::before { content: "▣"; }
.fa-circle-info::before { content: "ⓘ"; }
.fa-graduation-cap::before { content: "🎓"; }
.fa-person-chalkboard::before { content: "▤"; }
.fa-headphones::before { content: "🎧"; }
.fa-brain::before { content: "◆"; }
.fa-play::before { content: "▶"; }
.fa-chevron-down::before { content: "⌄"; }
.fa-chevron-left::before { content: "‹"; }
.fa-chevron-right::before { content: "›"; }
.fa-feather-alt::before { content: "✦"; }
.fa-quote-right::before { content: "❞"; }
.fa-shuffle::before { content: "⇄"; }
.fa-list-check::before { content: "☑"; }
.fa-fill-drip::before { content: "▥"; }
.fa-link::before { content: "🔗"; }
.fa-seedling::before { content: "🌱"; }
.fa-fire::before { content: "🔥"; }
.fa-bolt::before { content: "⚡"; }
.fa-sign-out-alt::before { content: "↪"; }
.fa-check::before { content: "✓"; }
.fa-times::before { content: "×"; }
.fa-redo::before { content: "↻"; }
.fa-star::before { content: "★"; }
.fa-comments::before { content: "💬"; }
.fa-calendar-check::before { content: "✓"; }
.fa-user-tie::before { content: "👤"; }
.fa-chart-line::before { content: "↗"; }
.fa-arrow-right::before { content: "→"; }
.fa-briefcase::before { content: "💼"; }
.fa-globe::before { content: "◎"; }
.fa-envelope-open-text::before { content: "✉"; }
.fa-envelope::before { content: "✉"; }
.fa-flask::before { content: "⚗"; }
.fa-arrow-trend-up::before { content: "↗"; }
.fa-stethoscope::before { content: "⚕"; }
.fa-gears::before { content: "⚙"; }
.fa-handshake::before { content: "🤝"; }
.fa-wand-magic-sparkles::before { content: "✦"; }
.fa-spell-check::before { content: "✓"; }
.fa-question-circle::before { content: "?"; }
.fa-crosshairs::before { content: "◎"; }
.fa-trophy::before { content: "🏆"; }

.footer-contact {
  margin-top: 0.65rem;
  font-size: 0.92rem;
  color: var(--muted, #64748b);
}
.footer-contact a {
  color: inherit;
  font-weight: 700;
  text-decoration: none;
}
.footer-contact a:hover {
  text-decoration: underline;
}