/* Study Chinese — Apple-style premium landing. Sunshine Coral tokens, cinematic spacing. */
:root {
  --paper: #FFF7F0;
  --surface: #FFF1E8;
  --card: #FFFFFF;
  --plum: #181219;
  --plum-2: #241A26;
  --plum-card: #2A2030;

  --ink: #221C28;
  --ink2: #5C5360;
  --muted: #6E6470;
  --on-dark: #F6F1EC;
  --on-dark2: #CBBFC9;

  --coral: #FF6B57;
  --coral-deep: #C0392B;
  --coral-soft: #FFE7DF;
  --teal: #3FB6A0;
  --teal-deep: #1B7060;
  --teal-soft: #DEF3EE;
  --amber: #FFB020;

  --border: #F0E2D6;
  --border-strong: #ECD8C7;
  --ring: #E04A38;

  --hero-grad: linear-gradient(135deg, #FF6B57, #FF9E4D);
  --shadow: 0 12px 34px rgba(34, 28, 40, .10);
  --shadow-lg: 0 30px 70px -26px rgba(34, 28, 40, .32);
  --shadow-xl: 0 50px 110px -40px rgba(34, 28, 40, .42);
  --shadow-coral: 0 18px 40px -16px rgba(255, 107, 87, .5);
  --clay-hi: inset 0 2px 0 rgba(255, 255, 255, .7);

  --r-sm: 14px; --r-md: 22px; --r-lg: 30px; --r-xl: 44px; --r-pill: 999px;
  --ease: cubic-bezier(.23, 1, .32, 1);
  --ease-out: cubic-bezier(.23, 1, .32, 1);
  --ease-in-out: cubic-bezier(.77, 0, .175, 1);
  --maxw: 1200px;
  --pad: clamp(80px, 13vw, 168px);  /* generous section rhythm */

  --f-display: 'Fredoka', system-ui, sans-serif;
  --f-body: 'Nunito', system-ui, sans-serif;
  --f-hanzi: 'Noto Serif SC', 'Songti SC', serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--f-body); color: var(--ink); background: var(--paper);
  line-height: 1.6; font-size: 17px; -webkit-font-smoothing: antialiased; overflow-x: hidden;
}
h1, h2, h3 { font-family: var(--f-display); line-height: 1.06; letter-spacing: -.02em; font-weight: 700; text-wrap: balance; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
:focus-visible { outline: 3px solid var(--ring); outline-offset: 3px; border-radius: 8px; }

.wrap { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: clamp(20px, 5vw, 40px); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }

.ic { width: 1.3em; height: 1.3em; display: inline-block; vertical-align: -.18em; flex: none; }
.ic-lg { width: 30px; height: 30px; }
.ic-sm { width: 16px; height: 16px; }

.eyebrow {
  display: inline-block; font-family: var(--f-display); font-weight: 600; font-size: .82rem; letter-spacing: .02em;
  color: var(--coral-deep); background: var(--coral-soft); padding: 7px 15px; border-radius: var(--r-pill); margin-bottom: 26px;
}

/* buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  font-family: var(--f-display); font-weight: 600; font-size: 1.02rem;
  padding: 15px 26px; border-radius: var(--r-pill); border: 0; cursor: pointer; white-space: nowrap;
  transition: transform .16s var(--ease-out), box-shadow .28s var(--ease-out), background .2s var(--ease-out), border-color .2s var(--ease-out), color .2s var(--ease-out);
}
.btn:active { transform: scale(.96); }
.btn-primary { background: var(--coral); color: var(--ink); box-shadow: var(--shadow-coral), var(--clay-hi); }
.btn-ghost-dark { background: transparent; color: var(--on-dark); border: 1.5px solid rgba(246, 241, 236, .3); }
@media (hover: hover) and (pointer: fine) {
  .btn-primary:hover { transform: translateY(-2px); box-shadow: 0 24px 48px -16px rgba(255, 107, 87, .68), var(--clay-hi); }
  .btn-ghost-dark:hover { border-color: var(--coral); color: #fff; transform: translateY(-2px); }
}

.badge {
  display: inline-flex; align-items: center; gap: 7px; font-family: var(--f-display); font-weight: 600; font-size: .82rem;
  color: var(--teal-deep); background: var(--teal-soft); padding: 6px 14px; border-radius: var(--r-pill); margin-bottom: 22px;
}
.badge .ic { color: var(--teal-deep); }
.badge-gold { color: var(--amber); background: rgba(255, 176, 32, .16); }
.badge-gold .ic { color: var(--amber); }

/* reveal */
.js .reveal { opacity: 0; transform: translateY(28px); filter: blur(8px); transition: opacity .8s var(--ease-out), transform .9s var(--ease-out), filter .7s var(--ease-out); will-change: transform, opacity, filter; }
.js .reveal.from-left { transform: translateX(-48px); }
.js .reveal.pop { transform: scale(.94); }
.js .reveal.in { opacity: 1; transform: none; filter: blur(0); will-change: auto; }

/* scroll progress */
.scroll-progress { position: fixed; inset: 0 0 auto 0; height: 3px; background: var(--coral); transform: scaleX(0); transform-origin: 0 50%; z-index: 60; }
@supports (animation-timeline: scroll()) {
  .scroll-progress { animation: sp linear both; animation-timeline: scroll(root); }
  @keyframes sp { to { transform: scaleX(1); } }
}

/* ============ NAV ============ */
.nav { position: sticky; top: 0; z-index: 50; transition: background .3s var(--ease-out), box-shadow .3s var(--ease-out); }
.nav-in { display: flex; align-items: center; gap: 18px; height: 70px; }
.nav.scrolled { background: rgba(255, 247, 240, .8); backdrop-filter: blur(18px) saturate(1.5); -webkit-backdrop-filter: blur(18px) saturate(1.5); box-shadow: 0 1px 0 var(--border); }
.brand { display: inline-flex; align-items: center; gap: 11px; font-family: var(--f-display); font-weight: 700; font-size: 1.2rem; flex: none; white-space: nowrap; }
.brand-mark { font-family: var(--f-hanzi); font-weight: 700; font-size: 1.35rem; color: #fff; width: 38px; height: 38px; display: grid; place-items: center; border-radius: 12px; background: var(--hero-grad); box-shadow: var(--shadow-coral); line-height: 1; }
.nav-links { display: flex; gap: 30px; margin-left: 26px; font-weight: 600; color: var(--ink2); font-size: .98rem; }
.nav-links a { transition: color .2s; }
.nav-links a:hover { color: var(--ink); }
.nav-right { margin-left: auto; display: flex; align-items: center; gap: 14px; }
.lang { display: inline-flex; background: var(--surface); border: 1px solid var(--border); border-radius: var(--r-pill); padding: 3px; }
.lang-b { font-family: var(--f-display); font-weight: 600; font-size: .85rem; color: var(--ink2); background: transparent; border: 0; cursor: pointer; padding: 6px 13px; border-radius: var(--r-pill); transition: all .2s var(--ease-out); }
.lang-b.is-on { background: var(--card); color: var(--ink); box-shadow: var(--shadow); }
.lang-b:active { transform: scale(.92); }
.nav-cta { padding: 11px 20px; font-size: .95rem; }

/* ============ HERO ============ */
.hero { position: relative; text-align: center; padding-top: clamp(48px, 9vw, 96px); overflow: hidden; }
.hero-glow { position: absolute; inset: -10% -10% auto -10%; height: 80%; pointer-events: none; z-index: -1;
  background: radial-gradient(60% 60% at 50% 0%, rgba(255, 158, 77, .26), transparent 70%),
              radial-gradient(50% 50% at 80% 20%, rgba(63, 182, 160, .14), transparent 70%); }
.hero-in { max-width: 880px; margin-inline: auto; }
.hero-title { font-size: clamp(2.6rem, 6.2vw, 5rem); margin-bottom: 24px; }
.hero-title em { font-style: normal; color: var(--coral-deep); position: relative; white-space: nowrap; }
.hero-title em::after { content: ""; position: absolute; left: 0; right: 0; bottom: .02em; height: .1em; background: var(--amber); border-radius: 4px; z-index: -1; opacity: .9; transform-origin: left center; transition: transform .8s var(--ease-out) .35s; }
.js .hero-title em::after { transform: scaleX(0); }
.js .hero-title.in em::after { transform: scaleX(1); }
.hero-sub { font-size: clamp(1.1rem, 1.7vw, 1.32rem); color: var(--ink2); max-width: 46ch; margin: 0 auto 34px; }
.hero-form { max-width: 460px; margin-inline: auto; }

/* waitlist form */
.waitlist-row { display: flex; gap: 10px; background: var(--card); padding: 8px; border-radius: var(--r-pill); box-shadow: var(--shadow); border: 1px solid var(--border); }
.field { flex: 1; min-width: 0; border: 0; background: transparent; font-family: var(--f-body); font-size: 1rem; font-weight: 600; color: var(--ink); padding: 8px 16px; }
.field::placeholder { color: var(--muted); font-weight: 500; }
.field:focus { outline: none; }
.waitlist-row:focus-within { border-color: var(--coral); box-shadow: var(--shadow), 0 0 0 3px var(--coral-soft); }
.waitlist .btn-primary { padding: 13px 22px; }
.form-note { font-size: .9rem; color: var(--muted); margin-top: 14px; }
.form-msg { font-size: .95rem; font-weight: 700; margin-top: 12px; min-height: 1.2em; }
.form-msg.ok { color: var(--teal-deep); }
.form-msg.err { color: var(--coral-deep); }

/* hero product reveal */
.hero-stage { position: relative; display: flex; justify-content: center; margin-top: clamp(48px, 8vw, 96px); padding-bottom: var(--pad); }
.floatzi { position: absolute; font-family: var(--f-hanzi); font-weight: 700; color: var(--coral); opacity: .12; animation: float 9s var(--ease-in-out) infinite alternate; z-index: -1; }
.floatzi.z1 { font-size: clamp(6rem, 16vw, 13rem); top: -6%; left: 4%; }
.floatzi.z2 { font-size: clamp(4rem, 10vw, 8rem); bottom: 16%; right: 5%; color: var(--teal); opacity: .14; animation-delay: -4s; }
@keyframes float { to { transform: translateY(-26px) rotate(3deg); } }

.phone { position: relative; width: clamp(248px, 30vw, 320px); aspect-ratio: 390 / 844; background: #fff; border-radius: 50px; padding: 11px; box-shadow: var(--shadow-xl), 0 0 0 2px var(--border); border: 1px solid var(--border); will-change: transform; }
.phone-shot { width: 100%; height: 100%; object-fit: cover; object-position: top; border-radius: 40px; background: var(--paper); }
.phone-hero { width: clamp(264px, 32vw, 340px); }

/* ============ SOCIAL ============ */
.social { padding: clamp(36px, 6vw, 56px) 0; }
.social-in { display: flex; flex-direction: column; align-items: center; gap: 20px; text-align: center; }
.social-title { font-family: var(--f-display); font-weight: 600; color: var(--ink2); font-size: 1.05rem; }
.social-cards { display: flex; gap: 12px; flex-wrap: wrap; justify-content: center; }
.social-card { display: inline-flex; align-items: center; gap: 9px; background: var(--card); border: 1px solid var(--border); border-radius: var(--r-pill); padding: 10px 18px; box-shadow: var(--shadow); font-family: var(--f-display); font-weight: 600; transition: transform .2s var(--ease-out), box-shadow .2s var(--ease-out); }
@media (hover: hover) and (pointer: fine) { .social-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lg); } }
.social-card:active { transform: scale(.97); }
.social-logo { width: 22px; height: 22px; }

/* ============ THESIS ============ */
.thesis { padding: var(--pad) 0; text-align: center; position: relative; overflow: hidden; }
.thesis-in { max-width: 880px; margin-inline: auto; position: relative; }
.thesis-mark { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -54%); font-family: var(--f-hanzi); font-weight: 700; font-size: clamp(18rem, 40vw, 34rem); color: var(--coral); opacity: .05; line-height: 1; pointer-events: none; z-index: -1; }
.thesis-title { font-size: clamp(2.2rem, 5.4vw, 4.2rem); margin-bottom: 24px; }
.thesis-body { font-size: clamp(1.15rem, 1.8vw, 1.45rem); color: var(--ink2); max-width: 40ch; margin-inline: auto; }

/* ============ STORY (sticky scroll) ============ */
.story { padding: var(--pad) 0; }
.story-eyebrow { display: block; }
.story-grid { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(32px, 6vw, 90px); align-items: start; }
.story-stage { position: sticky; top: 0; height: 100dvh; display: flex; align-items: center; justify-content: center; }
.story-phone { width: clamp(240px, 26vw, 300px); }
.story-shot { position: absolute; inset: 11px; width: calc(100% - 22px); height: calc(100% - 22px); object-fit: cover; object-position: top; border-radius: 40px; background: var(--paper); opacity: 0; transform: scale(1.02); transition: opacity .6s var(--ease-out), transform .6s var(--ease-out); }
.story-shot.is-active { opacity: 1; transform: scale(1); }
.story-steps { display: flex; flex-direction: column; }
.story-step { min-height: 86vh; display: flex; flex-direction: column; justify-content: center; opacity: .42; transition: opacity .4s var(--ease-out); }
.story-step.is-active { opacity: 1; }
.story-ic { display: inline-grid; place-items: center; width: 60px; height: 60px; border-radius: 18px; background: var(--coral-soft); color: var(--coral-deep); margin-bottom: 22px; }
.story-step h2 { font-size: clamp(1.9rem, 3.6vw, 3rem); margin-bottom: 16px; max-width: 16ch; }
.story-step p { color: var(--ink2); font-size: clamp(1.05rem, 1.5vw, 1.22rem); max-width: 42ch; }
.story-step .story-step-shot { display: none; }  /* desktop: the sticky stage handles the visual (out-specifies .shot) */
.shot { display: block; border-radius: 30px; overflow: hidden; background: var(--paper); box-shadow: var(--shadow-lg); }
.shot img { width: 100%; height: 100%; object-fit: cover; object-position: top; }

/* ============ DAILY MARQUEE ============ */
.daily { padding: var(--pad) 0; background: var(--surface); border-block: 1px solid var(--border); overflow: hidden; }
.daily-head { text-align: center; max-width: 620px; margin: 0 auto clamp(36px, 5vw, 56px); }
.daily-head h2 { font-size: clamp(1.9rem, 3.8vw, 3rem); }
.daily-head p { color: var(--ink2); margin-top: 14px; font-size: 1.12rem; }
.marquee { -webkit-mask-image: linear-gradient(90deg, transparent, #000 7%, #000 93%, transparent); mask-image: linear-gradient(90deg, transparent, #000 7%, #000 93%, transparent); }
.marquee-track { display: flex; gap: 18px; width: max-content; animation: marq 46s linear infinite; }
.marquee:hover .marquee-track { animation-play-state: paused; }
@keyframes marq { to { transform: translateX(-50%); } }
.vcard { background: var(--card); border: 1px solid var(--border); border-radius: var(--r-md); box-shadow: var(--shadow); padding: 22px 26px; display: flex; align-items: center; gap: 16px; flex: none; }
.vcard-solo { flex-direction: column; align-items: flex-start; min-width: 210px; }
.vc-side { display: flex; flex-direction: column; align-items: center; }
.vc-zh { font-family: var(--f-hanzi); font-weight: 700; font-size: 2.5rem; line-height: 1.1; color: var(--ink); }
.vc-py { color: var(--coral-deep); font-weight: 700; font-size: .95rem; margin-top: 2px; }
.vc-gl { color: var(--ink2); font-size: .9rem; }
.vc-vs { font-family: var(--f-display); font-weight: 700; color: var(--muted); font-size: .85rem; background: var(--surface); border-radius: var(--r-pill); padding: 4px 10px; }
.vc-tag { font-family: var(--f-display); font-weight: 600; font-size: .72rem; letter-spacing: .02em; color: var(--teal-deep); background: var(--teal-soft); padding: 3px 11px; border-radius: var(--r-pill); }
.vcard-solo .vc-zh { font-size: 2.2rem; margin-top: 6px; }
@media (hover: hover) and (pointer: fine) {
  .vcard { transition: transform .3s var(--ease-out), box-shadow .3s var(--ease-out); }
  .vcard:hover { transform: translateY(-5px) rotate(-1deg); box-shadow: var(--shadow-lg); }
}

/* ============ COMING SOON ============ */
.soon { padding: var(--pad) 0; }
.soon-in { display: grid; gap: 24px; }
.pillar { border-radius: var(--r-xl); overflow: hidden; }
.pillar-rmb { background: var(--card); border: 1px solid var(--border); box-shadow: var(--shadow); display: grid; grid-template-columns: 1.05fr .95fr; align-items: stretch; }
.pillar-copy { padding: clamp(34px, 5vw, 64px); align-self: center; }
.pillar-copy h2 { font-size: clamp(1.7rem, 3vw, 2.6rem); }
.pillar-copy p { color: var(--ink2); margin-top: 16px; max-width: 44ch; font-size: 1.1rem; }
.pill-points { list-style: none; display: flex; flex-wrap: wrap; gap: 10px 24px; margin: 24px 0 30px; }
.pill-points li { display: inline-flex; align-items: center; gap: 8px; font-weight: 700; color: var(--ink); }
.pill-points .ic { color: var(--teal-deep); }
.pillar-rmb .btn-ghost-dark { color: var(--ink); border-color: var(--border-strong); }
.pillar-rmb .pillar-art { position: relative; display: grid; place-items: center; min-height: 280px; background: linear-gradient(150deg, var(--teal-soft), #CFEFE7); }
.art-hanzi { font-family: var(--f-hanzi); font-weight: 700; font-size: clamp(9rem, 17vw, 14rem); color: var(--teal-deep); opacity: .24; line-height: 1; }
.art-ic { position: absolute; display: grid; place-items: center; width: 88px; height: 88px; border-radius: 26px; background: var(--card); color: var(--teal-deep); box-shadow: var(--shadow-lg); }
.art-ic .ic { width: 42px; height: 42px; }

.pillar-course { position: relative; background: linear-gradient(160deg, var(--plum-2), var(--plum)); color: var(--on-dark); padding: clamp(54px, 8vw, 110px) clamp(30px, 6vw, 80px); text-align: center; overflow: hidden; }
.pillar-course h2 { font-size: clamp(1.9rem, 3.6vw, 3rem); max-width: 20ch; margin: 0 auto 16px; position: relative; }
.pillar-course p { color: var(--on-dark2); max-width: 50ch; margin: 0 auto 30px; font-size: 1.15rem; position: relative; }
.pillar-course .badge { position: relative; }
.pillar-course .btn { position: relative; }
.art-hanzi-bg { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); font-family: var(--f-hanzi); font-weight: 700; font-size: clamp(20rem, 44vw, 40rem); color: #fff; opacity: .04; line-height: 1; pointer-events: none; }

/* ============ FINAL CTA ============ */
.final { background: var(--plum); color: var(--on-dark); padding: var(--pad) 0; position: relative; overflow: hidden; }
.final-in { max-width: 660px; margin-inline: auto; text-align: center; position: relative; }
.final-mark { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); font-family: var(--f-hanzi); font-weight: 700; font-size: clamp(22rem, 50vw, 42rem); color: #fff; opacity: .035; line-height: 1; pointer-events: none; z-index: 0; }
.final h2 { font-size: clamp(2.2rem, 5vw, 3.6rem); position: relative; }
.final p { color: var(--on-dark2); margin: 20px auto 34px; max-width: 46ch; font-size: 1.18rem; position: relative; }
.waitlist-dark { margin-inline: auto; max-width: 460px; position: relative; }
.waitlist-dark .waitlist-row { background: var(--plum-card); border-color: rgba(246, 241, 236, .16); box-shadow: none; }
.waitlist-dark .field { color: var(--on-dark); }
.waitlist-dark .field::placeholder { color: #9b8fa0; }
.waitlist-dark .waitlist-row:focus-within { border-color: var(--coral); box-shadow: 0 0 0 3px rgba(255, 107, 87, .25); }
.waitlist-dark .form-msg.ok { color: #5fdcb6; }
.waitlist-dark .form-msg.err { color: #ff9b8c; }
.final-follow { display: flex; align-items: center; justify-content: center; gap: 16px; margin-top: 32px; color: var(--on-dark2); font-weight: 700; position: relative; }
.follow-link { display: grid; place-items: center; width: 46px; height: 46px; border-radius: var(--r-pill); background: var(--plum-card); border: 1px solid rgba(246, 241, 236, .16); transition: transform .2s var(--ease-out), border-color .2s; }
@media (hover: hover) and (pointer: fine) { .follow-link:hover { transform: translateY(-3px); border-color: var(--coral); } }
.follow-link:active { transform: scale(.92); }

/* ============ FOOTER ============ */
.foot { background: var(--plum); color: var(--on-dark2); padding: clamp(44px, 6vw, 72px) 0 36px; border-top: 1px solid rgba(246, 241, 236, .1); }
.foot-in { display: flex; justify-content: space-between; gap: 32px; flex-wrap: wrap; }
.brand-light { color: var(--on-dark); }
.foot-tag { font-family: var(--f-display); font-weight: 600; color: var(--on-dark); margin-top: 16px; font-size: 1.1rem; }
.foot-made { font-size: .92rem; margin-top: 4px; }
.foot-links { display: flex; gap: 26px; flex-wrap: wrap; align-items: flex-start; font-weight: 700; }
.foot-links a { color: var(--on-dark2); transition: color .2s; }
.foot-links a:hover { color: #fff; }
.foot-bottom { margin-top: 40px; padding-top: 24px; border-top: 1px solid rgba(246, 241, 236, .1); font-size: .9rem; }

/* ============ RESPONSIVE ============ */
@media (max-width: 980px) {
  .story-grid { grid-template-columns: 1fr; gap: 0; }
  .story-stage { display: none; }                 /* mobile: inline per-step images instead of sticky */
  .story-step { min-height: 0; opacity: 1; padding: clamp(40px, 9vw, 64px) 0; }
  .story-step .story-step-shot { display: block; margin-top: 28px; max-width: 300px; }
  .pillar-rmb { grid-template-columns: 1fr; }
  .pillar-rmb .pillar-art { order: -1; min-height: 220px; }
}
@media (max-width: 860px) {
  .nav-links { display: none; }
}
@media (max-width: 520px) {
  body { font-size: 16px; }
  .nav-in { height: 62px; gap: 8px; }
  .nav-right { gap: 8px; }
  .brand-name { font-size: 1rem; }
  .nav-cta { padding: 9px 15px; font-size: .88rem; }
  .lang-b { padding: 8px 12px; font-size: .8rem; }
  .waitlist-row { flex-direction: column; background: transparent; border: 0; box-shadow: none; padding: 0; gap: 12px; }
  .waitlist-row .field { background: var(--card); border: 1px solid var(--border); border-radius: var(--r-pill); box-shadow: var(--shadow); padding: 15px 20px; width: 100%; }
  .waitlist .btn-primary { width: 100%; }
  .waitlist-dark .waitlist-row .field { background: var(--plum-card); border-color: rgba(246, 241, 236, .16); }
  .social-card { font-size: .92rem; }
}

/* ============ REDUCED MOTION ============ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal, .js .reveal, .js .reveal.from-left, .js .reveal.pop {
    opacity: 1 !important; transform: none !important; filter: none !important; transition: none !important;
  }
  .floatzi, .phone { animation: none !important; }
  .marquee-track { animation: none !important; }
  .marquee { overflow-x: auto; }
  .scroll-progress { display: none; }
  .hero-title em::after { transition: none !important; transform: none !important; }
  .story-shot { transition: none !important; }
  .btn, .social-card, .follow-link, .vcard, .story-step { transition: none; }
  .btn:active, .social-card:active, .follow-link:active, .lang-b:active { transform: none; }
}