:root {
  --bg: #09080F; --bg2: #13111D; --bg3: #1B1829; --ink: #F5F3FF; --mut: #A7A2BC; --line: rgba(255,255,255,.1);
  --pink: #FF2E88; --orange: #FF8A00; --sun: #FFC93C; --violet: #7B5CFF; --cyan: #23E5DB; --lime: #C6FF3D;
  --grad: linear-gradient(90deg, #FF2E88, #FF8A00 50%, #7B5CFF);
  --display: 'Unbounded', system-ui, sans-serif; --body: 'Plus Jakarta Sans', system-ui, sans-serif;
  --r: 18px;
}
* { box-sizing: border-box; margin: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { min-height: 100vh; background: var(--bg); color: var(--ink); font: 16px/1.6 var(--body); overflow-x: hidden; }
a { color: inherit; }
button, input, textarea { font: inherit; color: inherit; }
img { max-width: 100%; }
.bg { position: fixed; inset: 0; z-index: -1; overflow: hidden; pointer-events: none; }
.bg i { position: absolute; width: 46vmax; height: 46vmax; border-radius: 50%; filter: blur(90px); opacity: .32; animation: drift 22s ease-in-out infinite alternate; }
.bg .b1 { background: var(--pink); top: -18vmax; left: -12vmax; }
.bg .b2 { background: var(--violet); top: 10vmax; right: -18vmax; animation-delay: -7s; }
.bg .b3 { background: var(--orange); bottom: -24vmax; left: 20vmax; opacity: .2; animation-delay: -12s; }
@keyframes drift { to { transform: translate(6vmax, 4vmax) scale(1.12); } }
@media (prefers-reduced-motion: reduce) { .bg i, .reveal { animation: none !important; } }

.top { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px clamp(16px, 4vw, 40px); background: rgba(9,8,15,.72); backdrop-filter: blur(14px); border-bottom: 1px solid var(--line); }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; font-family: var(--display); font-weight: 900; font-size: 17px; letter-spacing: -.5px; }
.brand img { border-radius: 10px; }
.brand em { font-style: normal; font-family: var(--body); font-weight: 600; font-size: 12px; color: var(--mut); margin-left: 4px; letter-spacing: 0; }
.top-nav { display: flex; align-items: center; gap: 6px; }
.top-nav > a { padding: 8px 12px; border-radius: 999px; text-decoration: none; font-weight: 700; font-size: 14px; color: var(--mut); }
.top-nav > a.on, .top-nav > a:hover { color: var(--ink); background: rgba(255,255,255,.07); }
#app { display: block; max-width: 1180px; margin: 0 auto; padding: 0 clamp(16px, 4vw, 40px) 60px; outline: none; }
.loading { padding: 80px 0; text-align: center; color: var(--mut); }

.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 46px; padding: 0 22px; border-radius: 999px; border: 0; cursor: pointer; font-weight: 800; font-size: 15px; text-decoration: none; transition: transform .15s ease, box-shadow .2s ease, opacity .2s; white-space: nowrap; }
.btn:hover { transform: translateY(-2px); }
.btn:disabled { opacity: .5; cursor: not-allowed; transform: none; }
.btn-grad { background: var(--grad); color: #fff; box-shadow: 0 12px 30px -10px rgba(255,46,136,.7); }
.btn-glass { background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.18); color: var(--ink); }
.btn-white { background: #fff; color: #09080F; }
.btn-sm { min-height: 36px; padding: 0 14px; font-size: 13px; }
.link { background: none; border: 0; color: var(--mut); text-decoration: underline; cursor: pointer; font-weight: 600; }
.g { background: linear-gradient(90deg, var(--pink), var(--orange), var(--sun), var(--cyan)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.chip { display: inline-flex; align-items: center; gap: 6px; padding: 6px 12px; border-radius: 999px; font-size: 13px; font-weight: 700; background: rgba(255,255,255,.08); border: 1px solid var(--line); }
.mut { color: var(--mut); }

/* Home */
.hero { padding: clamp(48px, 9vw, 110px) 0 40px; display: grid; grid-template-columns: 1.15fr .85fr; gap: 40px; align-items: center; }
.hero h1 { font-family: var(--display); font-weight: 900; font-size: clamp(40px, 7vw, 84px); line-height: .95; letter-spacing: -3px; }
.hero p.lede { margin-top: 22px; font-size: clamp(17px, 2vw, 21px); color: #DAD6EA; max-width: 560px; }
.hero .cta { margin-top: 30px; display: flex; gap: 12px; flex-wrap: wrap; }
.hero .badges { margin-top: 26px; display: flex; gap: 8px; flex-wrap: wrap; }
.hero-card { position: relative; padding: 22px; border-radius: 26px; background: linear-gradient(160deg, rgba(255,255,255,.1), rgba(255,255,255,.03)); border: 1px solid rgba(255,255,255,.14); box-shadow: 0 40px 90px -30px rgba(0,0,0,.8); }
.hero-card .bubble { max-width: 88%; padding: 12px 16px; border-radius: 18px; margin-bottom: 10px; font-size: 15px; animation: pop .5s both; }
.hero-card .bubble.ai { background: rgba(255,255,255,.09); border-bottom-left-radius: 6px; }
.hero-card .bubble.me { margin-left: auto; background: var(--grad); border-bottom-right-radius: 6px; }
.hero-card .bubble:nth-child(2) { animation-delay: .6s; } .hero-card .bubble:nth-child(3) { animation-delay: 1.3s; } .hero-card .bubble:nth-child(4) { animation-delay: 2s; }
.hero-card .who { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; font-weight: 800; }
.hero-card .who b { width: 38px; height: 38px; border-radius: 50%; display: grid; place-items: center; background: linear-gradient(135deg, var(--violet), var(--pink)); }
.hero-card .who small { display: block; color: var(--lime); font-weight: 700; font-size: 12px; }
@keyframes pop { from { opacity: 0; transform: translateY(10px) scale(.96); } }

.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin: 30px 0 60px; }
.feature { padding: 24px; border-radius: var(--r); background: var(--bg2); border: 1px solid var(--line); }
.feature .ic { width: 52px; height: 52px; border-radius: 16px; display: grid; place-items: center; font-size: 24px; margin-bottom: 14px; }
.feature h3 { font-family: var(--display); font-size: 18px; letter-spacing: -.3px; }
.feature p { margin-top: 6px; color: var(--mut); font-size: 15px; }

.section-title { font-family: var(--display); font-weight: 900; font-size: clamp(28px, 4vw, 44px); letter-spacing: -1.5px; line-height: 1; }
.path-head { display: flex; justify-content: space-between; align-items: end; gap: 16px; flex-wrap: wrap; margin-bottom: 20px; }
.meter { display: flex; align-items: center; gap: 12px; font-weight: 700; color: var(--mut); }
.meter .bar { width: 180px; height: 10px; border-radius: 99px; background: rgba(255,255,255,.1); overflow: hidden; }
.meter .bar i { display: block; height: 100%; background: var(--grad); border-radius: 99px; transition: width .6s ease; }
.path { display: grid; gap: 12px; }
.lesson-row { display: grid; grid-template-columns: 64px 1fr auto; gap: 18px; align-items: center; padding: 18px 20px; border-radius: var(--r); background: var(--bg2); border: 1px solid var(--line); text-decoration: none; transition: border-color .2s, transform .2s; }
.lesson-row:hover { border-color: rgba(255,46,136,.5); transform: translateX(4px); }
.lesson-row .num { width: 64px; height: 64px; border-radius: 18px; display: grid; place-items: center; font-family: var(--display); font-weight: 900; font-size: 24px; background: rgba(255,255,255,.06); }
.lesson-row.done .num { background: var(--lime); color: #09080F; }
.lesson-row h3 { font-size: 19px; font-weight: 800; }
.lesson-row p { color: var(--mut); font-size: 14.5px; margin-top: 2px; }
.lesson-row .go { font-weight: 800; font-size: 14px; color: var(--mut); white-space: nowrap; }
.lesson-row.done .go { color: var(--lime); }
.cert-cta { margin: 26px 0 0; padding: 26px; border-radius: 24px; display: flex; gap: 20px; align-items: center; justify-content: space-between; flex-wrap: wrap; background: linear-gradient(120deg, rgba(255,46,136,.22), rgba(123,92,255,.22)); border: 1px solid rgba(255,255,255,.16); }
.cert-cta h3 { font-family: var(--display); font-size: 22px; letter-spacing: -.5px; }

/* Lesson */
.lesson { display: grid; grid-template-columns: minmax(0, 1fr) 400px; gap: 28px; padding-top: 28px; align-items: start; }
.crumbs { display: flex; gap: 8px; align-items: center; color: var(--mut); font-size: 14px; font-weight: 600; }
.crumbs a { text-decoration: none; }
.lesson h1 { margin-top: 14px; font-family: var(--display); font-weight: 900; font-size: clamp(32px, 5vw, 54px); letter-spacing: -2px; line-height: 1; }
.lesson .summary { margin-top: 14px; font-size: 18px; color: #DAD6EA; }
.lesson .meta { margin-top: 14px; display: flex; gap: 8px; flex-wrap: wrap; }
.block { margin-top: 26px; padding: 26px; border-radius: 22px; background: var(--bg2); border: 1px solid var(--line); }
.block h2 { font-family: var(--display); font-size: 21px; letter-spacing: -.5px; margin-bottom: 10px; }
.prose p + p, .prose p + ul, .prose ul + p, .prose ol + p, .prose p + ol { margin-top: 12px; }
.prose ul, .prose ol { padding-left: 22px; }
.prose li + li { margin-top: 6px; }
.prose strong { color: #fff; }
.prose code { padding: 1px 6px; border-radius: 6px; background: rgba(255,255,255,.1); font-size: .92em; }

.try h2 { display: flex; align-items: center; gap: 10px; }
.try-buttons { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }
.try-box { margin-top: 14px; display: grid; gap: 10px; }
.try-box textarea, .chat-form textarea, .field input { width: 100%; padding: 14px 16px; border-radius: 14px; border: 1px solid rgba(255,255,255,.16); background: rgba(0,0,0,.35); resize: vertical; outline: none; transition: border-color .2s; }
.try-box textarea:focus, .chat-form textarea:focus, .field input:focus { border-color: var(--pink); }
.try-actions { display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; }
.answer { margin-top: 4px; padding: 18px; border-radius: 16px; background: rgba(255,255,255,.05); border: 1px solid var(--line); }
.answer .label { font-size: 12px; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; color: var(--cyan); margin-bottom: 8px; }
.answer table { border-collapse: collapse; width: 100%; font-size: 14px; margin-top: 8px; }
.answer th, .answer td { border: 1px solid var(--line); padding: 6px 8px; text-align: left; }

.quiz .q { margin-top: 18px; }
.quiz .q > p { font-weight: 800; }
.quiz .opts { display: grid; gap: 8px; margin-top: 10px; }
.quiz label { display: flex; gap: 10px; align-items: flex-start; padding: 12px 14px; border-radius: 14px; border: 1px solid var(--line); background: rgba(255,255,255,.03); cursor: pointer; transition: border-color .2s, background .2s; }
.quiz label:hover { border-color: rgba(255,255,255,.3); }
.quiz input { margin-top: 5px; accent-color: var(--pink); }
.quiz label.right { border-color: var(--lime); background: rgba(198,255,61,.08); }
.quiz label.wrong { border-color: #FF5C6C; background: rgba(255,92,108,.08); }
.quiz .why { margin-top: 8px; font-size: 14px; color: var(--mut); }
.result { margin-top: 18px; padding: 16px 18px; border-radius: 16px; font-weight: 700; }
.result.pass { background: rgba(198,255,61,.12); color: var(--lime); }
.result.fail { background: rgba(255,138,0,.12); color: #FFC07A; }
.next-row { margin-top: 18px; display: flex; gap: 10px; flex-wrap: wrap; }

/* Tutor */
.tutor { position: sticky; top: 86px; display: flex; flex-direction: column; height: calc(100vh - 110px); max-height: 760px; border-radius: 24px; background: var(--bg2); border: 1px solid rgba(255,255,255,.14); overflow: hidden; box-shadow: 0 30px 80px -30px rgba(0,0,0,.8); }
.tutor-head { display: flex; align-items: center; gap: 12px; padding: 14px 16px; border-bottom: 1px solid var(--line); background: linear-gradient(120deg, rgba(123,92,255,.25), rgba(255,46,136,.2)); }
.tutor-head .av { width: 42px; height: 42px; border-radius: 50%; display: grid; place-items: center; font-size: 20px; background: linear-gradient(135deg, var(--violet), var(--pink)); flex: none; }
.tutor-head strong { display: block; }
.tutor-head small { color: var(--lime); font-weight: 700; }
.tutor-head .x { margin-left: auto; display: flex; gap: 6px; }
.icon-btn { width: 36px; height: 36px; display: grid; place-items: center; border-radius: 10px; border: 1px solid var(--line); background: rgba(255,255,255,.06); cursor: pointer; }
.msgs { flex: 1; overflow-y: auto; padding: 16px; display: flex; flex-direction: column; gap: 10px; scroll-behavior: smooth; }
.msg { max-width: 90%; padding: 11px 14px; border-radius: 18px; font-size: 15px; line-height: 1.5; word-wrap: break-word; }
.msg.model { background: rgba(255,255,255,.07); border-bottom-left-radius: 6px; }
.msg.user { margin-left: auto; background: var(--grad); border-bottom-right-radius: 6px; white-space: pre-wrap; }
.msg.err { background: rgba(255,92,108,.12); color: #FFB3BB; }
.typing { display: inline-flex; gap: 5px; padding: 14px 16px; }
.typing i { width: 8px; height: 8px; border-radius: 50%; background: #fff; opacity: .4; animation: blink 1.2s infinite; }
.typing i:nth-child(2) { animation-delay: .2s; } .typing i:nth-child(3) { animation-delay: .4s; }
@keyframes blink { 50% { opacity: 1; transform: translateY(-3px); } }
.chat-form { padding: 12px; border-top: 1px solid var(--line); display: grid; gap: 8px; }
.chat-form .row { display: flex; gap: 8px; align-items: flex-end; }
.chat-form textarea { min-height: 48px; max-height: 140px; resize: none; }
.chat-form .send { width: 48px; height: 48px; padding: 0; flex: none; }
.usage { font-size: 12px; color: var(--mut); display: flex; justify-content: space-between; }
.gate { flex: 1; display: grid; place-content: center; text-align: center; gap: 14px; padding: 26px; }
.gate h3 { font-family: var(--display); font-size: 20px; }
.tutor-fab { display: none; }

/* Modal */
.modal-bg { position: fixed; inset: 0; z-index: 50; display: grid; place-items: center; padding: 16px; background: rgba(5,4,10,.75); backdrop-filter: blur(6px); animation: fade .2s; }
@keyframes fade { from { opacity: 0; } }
.modal { width: min(440px, 100%); max-height: calc(100vh - 32px); overflow: auto; padding: 26px; border-radius: 24px; background: var(--bg2); border: 1px solid rgba(255,255,255,.16); }
.modal h2 { font-family: var(--display); font-size: 24px; letter-spacing: -.8px; }
.modal .sub { color: var(--mut); margin-top: 6px; }
.tabs { display: flex; gap: 6px; margin-top: 18px; padding: 4px; border-radius: 14px; background: rgba(0,0,0,.35); }
.tabs button { flex: 1; padding: 10px; border: 0; border-radius: 10px; background: none; font-weight: 800; color: var(--mut); cursor: pointer; }
.tabs button.on { background: rgba(255,255,255,.1); color: var(--ink); }
.form { display: grid; gap: 12px; margin-top: 16px; }
.field { display: grid; gap: 6px; font-weight: 700; font-size: 14px; }
.field .err { color: #FF8A95; font-weight: 600; font-size: 13px; }
.check { display: flex; gap: 10px; align-items: flex-start; font-size: 14px; color: #DAD6EA; }
.check input { margin-top: 4px; accent-color: var(--pink); width: 16px; height: 16px; flex: none; }
.form-err { padding: 10px 12px; border-radius: 12px; background: rgba(255,92,108,.14); color: #FFB3BB; font-weight: 600; font-size: 14px; }
.fine { color: var(--mut); font-size: 12.5px; }

/* Account chip */
.acct { display: inline-flex; align-items: center; gap: 8px; margin-left: 4px; }
.acct .name { font-weight: 800; font-size: 14px; max-width: 140px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* Certificate */
.cert-page { padding: 40px 0; display: grid; gap: 20px; justify-items: center; }
.cert { width: min(860px, 100%); aspect-ratio: 1.414; position: relative; overflow: hidden; border-radius: 22px; background: #fff; color: #15131F; padding: 6% 7%; display: flex; flex-direction: column; justify-content: space-between; box-shadow: 0 40px 100px -30px rgba(0,0,0,.9); }
.cert::before { content: ""; position: absolute; inset: 0; background: radial-gradient(40% 50% at 0% 0%, rgba(255,46,136,.18), transparent 70%), radial-gradient(40% 50% at 100% 100%, rgba(123,92,255,.2), transparent 70%); }
.cert > * { position: relative; }
.cert .c-top { display: flex; justify-content: space-between; align-items: center; }
.cert .c-brand { display: flex; align-items: center; gap: 10px; font-family: var(--display); font-weight: 900; font-size: clamp(14px, 2.2vw, 20px); }
.cert .c-brand img { width: clamp(30px, 5vw, 46px); border-radius: 10px; }
.cert .c-label { font-size: clamp(9px, 1.4vw, 13px); font-weight: 800; letter-spacing: .2em; text-transform: uppercase; color: #7A7590; }
.cert h1 { font-family: var(--display); font-weight: 900; font-size: clamp(22px, 5vw, 52px); letter-spacing: -2px; line-height: 1; }
.cert .c-name { font-family: var(--display); font-weight: 700; font-size: clamp(20px, 4.4vw, 44px); letter-spacing: -1px; background: linear-gradient(90deg, #FF2E88, #FF8A00, #7B5CFF); -webkit-background-clip: text; background-clip: text; color: transparent; padding-bottom: .1em; }
.cert .c-text { font-size: clamp(11px, 1.8vw, 17px); color: #3A3650; max-width: 80%; }
.cert .c-foot { display: flex; justify-content: space-between; align-items: end; gap: 12px; font-size: clamp(9px, 1.5vw, 13px); color: #5C5873; }
.cert .c-foot b { display: block; color: #15131F; font-size: 1.15em; }

/* Footer */
.foot { max-width: 1180px; margin: 40px auto 0; padding: 30px clamp(16px, 4vw, 40px) 40px; border-top: 1px solid var(--line); display: grid; grid-template-columns: 1fr auto; gap: 16px 30px; align-items: center; }
.foot strong { display: block; font-family: var(--display); font-size: 18px; letter-spacing: -.3px; }
.foot span { color: var(--mut); }
.foot-links { display: flex; gap: 10px; flex-wrap: wrap; }
.foot .fine { grid-column: 1 / -1; }

.reveal { animation: up .6s cubic-bezier(.2,.8,.2,1) both; }
@keyframes up { from { opacity: 0; transform: translateY(18px); } }
.toast { position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%); z-index: 60; padding: 12px 18px; border-radius: 14px; background: #fff; color: #09080F; font-weight: 800; box-shadow: 0 20px 50px rgba(0,0,0,.5); animation: up .3s both; }

@media (max-width: 1000px) {
  .lesson { grid-template-columns: 1fr; }
  .tutor { position: fixed; inset: auto 0 0 0; z-index: 40; height: 82vh; max-height: none; border-radius: 24px 24px 0 0; transform: translateY(105%); transition: transform .3s cubic-bezier(.2,.8,.2,1); }
  .tutor.open { transform: none; }
  .tutor-fab { display: inline-flex; position: fixed; right: 16px; bottom: calc(16px + env(safe-area-inset-bottom)); z-index: 30; box-shadow: 0 16px 40px -10px rgba(255,46,136,.8); }
  .tutor-head .close-sheet { display: grid; }
}
.tutor-head .close-sheet { display: none; }
@media (max-width: 820px) {
  .hero { grid-template-columns: 1fr; padding-top: 40px; }
  .features { grid-template-columns: 1fr; }
  .lesson-row { grid-template-columns: 48px 1fr; }
  .lesson-row .num { width: 48px; height: 48px; font-size: 18px; border-radius: 14px; }
  .lesson-row .go { grid-column: 2; }
  .foot { grid-template-columns: 1fr; }
  .brand em { display: none; }
  .top-nav > a[data-nav="certificate"] { display: none; }
  .block { padding: 20px; }
}
@media print {
  body { background: #fff; }
  .top, .foot, .bg, .no-print, .tutor-fab { display: none !important; }
  #app { padding: 0; max-width: none; }
  .cert-page { padding: 0; }
  .cert { width: 100%; box-shadow: none; border-radius: 0; -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  @page { size: A4 landscape; margin: 0; }
}

/* Utility classes (no inline styles: the CSP blocks them) */
.mt18 { margin-top: 18px; }
.mt-s { margin-top: .3em; }
.mt-m { margin-top: .6em; }
.center { text-align: center; }
.narrow { max-width: 520px; }
.w640 { width: min(640px, 100%); }
.big-emoji { font-size: 42px; }
.chip.lime { color: var(--lime); }
.label.bad { color: #FF8A95; }
fieldset.q { border: 0; padding: 0; margin: 0; }
.feature .ic[data-tone="violet"] { background: rgba(123, 92, 255, .2); }
.feature .ic[data-tone="pink"] { background: rgba(255, 46, 136, .2); }
.feature .ic[data-tone="lime"] { background: rgba(198, 255, 61, .18); }