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

    .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 { 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: 620px; 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: 520px; }
    .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: 470px; }
    .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(150px,28%,230px), 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); }

    .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;
}