/* =========================================================================
   「쌤에게」 랜딩페이지 — styles.css
   비주얼 시스템: visual-designer 확정 토큰 그대로 승계
   ========================================================================= */

:root {
  /* --- Primary (쌤블루) --- */
  --color-primary-600: #3B4FD8;
  --color-primary-700: #2E3EB0;
  --color-primary-500: #4A60E8;
  --color-primary-50: #EEF1FE;
  /* --- Secondary (코랄, 강조 전용) --- */
  --color-secondary-500: #F5643C;
  --color-secondary-400: #FF8A6B;
  --color-secondary-50: #FFF2EE;
  /* --- Neutral (웜뉴트럴) --- */
  --neutral-0: #ffffff;
  --neutral-700: #4A443E;
  --neutral-900: #22201D;
  --neutral-500: #78716A;
  --neutral-200: #E7E3DE;
  /* --- Special surfaces --- */
  --hero-ink: #171E5C;
  --surface-b: #F6F4FB;
  --surface-tint: #EEF1FE;
  /* --- Gradients --- */
  --grad-hero: linear-gradient(155deg, #2E3EB0, #3B4FD8 42%, #4A60E8);
  --grad-cta: linear-gradient(135deg, #3B4FD8, #2E3EB0);
  --grad-coral: linear-gradient(135deg, #FF8A6B, #F5643C);
  /* --- Blobs --- */
  --blob-1: rgba(74, 96, 232, .55);
  --blob-2: rgba(139, 110, 255, .40);
  --blob-3: rgba(245, 100, 60, .28);
  /* --- Glass --- */
  --glass-bg: rgba(255, 255, 255, .72);
  --glass-border: rgba(255, 255, 255, .55);
  /* --- Shadows --- */
  --shadow-2: 0 8px 24px rgba(34, 32, 29, .09);
  --shadow-3: 0 20px 48px rgba(34, 32, 29, .14);
  --shadow-float: 0 32px 64px -12px rgba(23, 30, 92, .32);
  --shadow-glow: 0 8px 28px rgba(59, 79, 216, .38);
  /* --- Radius --- */
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-pill: 999px;
  /* --- Type scale --- */
  --fs-hero: clamp(2.125rem, 1.2rem + 4.6vw, 4.5rem);
  --fs-display: clamp(1.75rem, 1.2rem + 2.4vw, 3rem);
  --fs-stat: clamp(2.5rem, 1.8rem + 3vw, 4rem);
  --container: 1200px;
  --section-y: clamp(4rem, 2.5rem + 6vw, 7.5rem);
}

/* ============================ RESET ============================ */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}
body {
  font-family: "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont,
    system-ui, "Segoe UI", Roboto, "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  color: var(--neutral-900);
  background: var(--neutral-0);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
img, svg { display: block; max-width: 100%; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4 { line-height: 1.2; word-break: keep-all; }
ul { list-style: none; padding: 0; }
:focus-visible {
  outline: 3px solid var(--color-primary-500);
  outline-offset: 2px;
  border-radius: 4px;
}
.tabular { font-variant-numeric: tabular-nums; }
.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;
}
.skip-link {
  position: absolute; left: 12px; top: -60px; z-index: 200;
  background: var(--neutral-900); color: #fff; padding: .7rem 1.1rem;
  border-radius: 10px; transition: top .2s ease;
}
.skip-link:focus { top: 12px; }

/* ============================ LAYOUT ============================ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: clamp(1.1rem, 4vw, 2rem);
}
section { position: relative; }
.section-pad { padding-block: var(--section-y); }
.section-tint { background: var(--surface-b); }
.eyebrow {
  display: inline-flex; align-items: center; gap: .5rem;
  font-size: .82rem; font-weight: 700; letter-spacing: .01em;
  color: var(--color-primary-600);
  background: var(--color-primary-50);
  padding: .4rem .9rem; border-radius: var(--radius-pill);
}
.eyebrow .dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--color-secondary-500);
}
.section-head { max-width: 720px; margin-bottom: clamp(2rem, 4vw, 3.5rem); }
.section-head.center { margin-inline: auto; text-align: center; }
.section-head h2 {
  font-size: var(--fs-display); font-weight: 800; letter-spacing: -0.02em;
  margin-top: .9rem;
}
.section-head p {
  margin-top: 1rem; font-size: 1.06rem; color: var(--neutral-700);
}
.coral { color: var(--color-secondary-500); }
.muted { color: var(--neutral-500); }

/* ============================ BUTTONS ============================ */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  font-weight: 700; font-size: 1rem;
  padding: .95rem 1.6rem; border-radius: var(--radius-pill);
  min-height: 52px; min-width: 44px;
  transition: transform .18s ease, box-shadow .25s ease, background-color .2s ease;
  position: relative; overflow: hidden; white-space: nowrap;
}
.btn-primary {
  background: var(--grad-cta); color: #fff;
  box-shadow: var(--shadow-glow);
}
.btn-primary::after {
  /* 광택 스윕 */
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(115deg, transparent 30%, rgba(255,255,255,.45) 50%, transparent 70%);
  transform: translateX(-120%);
  transition: transform .6s ease;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 36px rgba(59,79,216,.48); }
.btn-primary:hover::after { transform: translateX(120%); }
.btn-coral { background: var(--grad-coral); color: #fff; box-shadow: 0 8px 26px rgba(245,100,60,.36); }
.btn-coral:hover { transform: translateY(-2px); box-shadow: 0 14px 34px rgba(245,100,60,.46); }
.btn-coral::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(115deg, transparent 30%, rgba(255,255,255,.45) 50%, transparent 70%);
  transform: translateX(-120%); transition: transform .6s ease;
}
.btn-coral:hover::after { transform: translateX(120%); }
.btn-ghost {
  background: transparent; color: var(--color-primary-600);
  border: 1.5px solid var(--neutral-200);
}
.btn-ghost:hover { border-color: var(--color-primary-500); background: var(--color-primary-50); transform: translateY(-1px); }
.btn-ghost-light {
  background: rgba(255,255,255,.12); color: #fff;
  border: 1.5px solid rgba(255,255,255,.4); backdrop-filter: blur(6px);
}
.btn-ghost-light:hover { background: rgba(255,255,255,.22); transform: translateY(-1px); }
.btn-lg { padding: 1.1rem 2rem; font-size: 1.08rem; min-height: 58px; }
.btn-block { display: flex; width: 100%; }

@media (prefers-reduced-motion: reduce) {
  .btn, .btn:hover { transform: none; }
  .btn-primary::after, .btn-coral::after { display: none; }
}

/* ============================ HEADER (S0) ============================ */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  transition: background-color .3s ease, box-shadow .3s ease, backdrop-filter .3s ease;
}
.site-header .bar {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; height: 68px;
}
.brand { display: flex; align-items: center; gap: .55rem; font-weight: 800; font-size: 1.22rem; letter-spacing: -0.02em; }
.brand .logo-mark {
  width: 30px; height: 30px; border-radius: 9px;
  background: var(--grad-cta); display: grid; place-items: center;
  color: #fff; font-size: .95rem; font-weight: 800;
  box-shadow: var(--shadow-glow);
}
.brand .brand-name { color: #fff; transition: color .3s ease; }
.nav-links { display: flex; align-items: center; gap: .3rem; }
.nav-links a {
  padding: .55rem .9rem; border-radius: 10px; font-weight: 600; font-size: .96rem;
  color: rgba(255,255,255,.82); transition: color .2s ease, background-color .2s ease;
}
.nav-links a:hover { color: #fff; background: rgba(255,255,255,.12); }
.header-cta { display: flex; align-items: center; gap: .6rem; }
.header-cta .btn { min-height: 44px; padding: .6rem 1.2rem; font-size: .95rem; }

/* scrolled → 흰 글래스 */
.site-header[data-scrolled="true"] {
  background: var(--glass-bg);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  box-shadow: 0 1px 0 rgba(34,32,29,.06), var(--shadow-2);
}
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .site-header[data-scrolled="true"] { background: rgba(255,255,255,.97); }
}
.site-header[data-scrolled="true"] .brand-name { color: var(--neutral-900); }
.site-header[data-scrolled="true"] .nav-links a { color: var(--neutral-700); }
.site-header[data-scrolled="true"] .nav-links a:hover { color: var(--color-primary-600); background: var(--color-primary-50); }

.nav-toggle { display: none; width: 44px; height: 44px; border-radius: 10px; align-items: center; justify-content: center; }
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after {
  content: ""; display: block; width: 22px; height: 2px; border-radius: 2px;
  background: #fff; position: relative; transition: background-color .3s ease;
}
.nav-toggle span::before { position: absolute; top: -7px; }
.nav-toggle span::after { position: absolute; top: 7px; }
.site-header[data-scrolled="true"] .nav-toggle span,
.site-header[data-scrolled="true"] .nav-toggle span::before,
.site-header[data-scrolled="true"] .nav-toggle span::after { background: var(--neutral-900); }

/* ============================ HERO (S1) ============================ */
.hero {
  position: relative; overflow: hidden;
  background: var(--hero-ink);
  color: #fff;
  padding-top: clamp(7rem, 6rem + 6vw, 10rem);
  padding-bottom: clamp(4rem, 3rem + 5vw, 7rem);
}
.hero .aurora { position: absolute; inset: 0; overflow: hidden; z-index: 0; }
.hero .blob {
  position: absolute; border-radius: 50%; filter: blur(60px);
  will-change: transform;
}
.hero .blob-1 { width: 52vw; height: 52vw; max-width: 680px; max-height: 680px;
  background: radial-gradient(circle, var(--blob-1), transparent 68%);
  top: -12%; left: -8%; animation: drift1 18s ease-in-out infinite; }
.hero .blob-2 { width: 46vw; height: 46vw; max-width: 620px; max-height: 620px;
  background: radial-gradient(circle, var(--blob-2), transparent 68%);
  top: 8%; right: -10%; animation: drift2 22s ease-in-out infinite; }
.hero .blob-3 { width: 40vw; height: 40vw; max-width: 520px; max-height: 520px;
  background: radial-gradient(circle, var(--blob-3), transparent 70%);
  bottom: -18%; left: 30%; animation: drift3 26s ease-in-out infinite; }
.hero .grain {
  position: absolute; inset: 0; z-index: 1; opacity: .5; pointer-events: none;
  mix-blend-mode: overlay;
}
@keyframes drift1 { 0%,100%{transform:translate(0,0) scale(1);} 50%{transform:translate(6%,8%) scale(1.08);} }
@keyframes drift2 { 0%,100%{transform:translate(0,0) scale(1);} 50%{transform:translate(-7%,5%) scale(1.05);} }
@keyframes drift3 { 0%,100%{transform:translate(0,0) scale(1);} 50%{transform:translate(4%,-6%) scale(1.1);} }

.hero .container { position: relative; z-index: 2; }
.hero-grid {
  display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(2rem, 4vw, 4rem);
  align-items: center;
}
.hero-copy .eyebrow { background: rgba(255,255,255,.14); color: #fff; }
.hero-copy .eyebrow .dot { background: var(--color-secondary-400); box-shadow: 0 0 10px var(--color-secondary-400); }
.hero h1 {
  font-size: var(--fs-hero); font-weight: 800; letter-spacing: -0.03em;
  margin-top: 1.3rem; line-height: 1.12;
}
.hero h1 .accent { color: var(--color-secondary-400); }
.hero-sub {
  margin-top: 1.4rem; font-size: clamp(1rem, .95rem + .4vw, 1.2rem);
  color: rgba(255,255,255,.86); max-width: 34em;
}
.hero-cta { display: flex; flex-wrap: wrap; gap: .8rem; margin-top: 2rem; }
.friction-badges {
  display: flex; flex-wrap: wrap; gap: .5rem 1.2rem; margin-top: 1.6rem;
  font-size: .92rem; color: rgba(255,255,255,.8);
}
.friction-badges li { display: flex; align-items: center; gap: .45rem; }
.friction-badges li::before {
  content: "✓"; color: var(--color-secondary-400); font-weight: 800;
}

/* --- 플로팅 폰 목업 --- */
.hero-visual { display: flex; justify-content: center; perspective: 1400px; }
.phone-stage { position: relative; }
.phone {
  position: relative; width: clamp(240px, 26vw, 300px); aspect-ratio: 300 / 620;
  border-radius: 42px; background: #0f1230;
  padding: 12px;
  box-shadow: var(--shadow-float), inset 0 0 0 2px rgba(255,255,255,.08);
  transform: rotateY(-14deg) rotateX(6deg) rotateZ(-1deg);
  animation: floatY 6s ease-in-out infinite;
  will-change: transform;
}
.phone::before {
  /* 코랄 후광 */
  content: ""; position: absolute; inset: -18% -14%; z-index: -1;
  background: radial-gradient(circle at 60% 40%, var(--blob-3), transparent 62%);
  filter: blur(30px);
}
@keyframes floatY { 0%,100%{transform:rotateY(-14deg) rotateX(6deg) translateY(0);} 50%{transform:rotateY(-11deg) rotateX(6deg) translateY(-14px);} }
.phone-screen {
  height: 100%; border-radius: 32px; background: linear-gradient(180deg,#fbfcff,#f2f4fb);
  overflow: hidden; display: flex; flex-direction: column;
  color: var(--neutral-900);
}
.phone-notch { height: 26px; display: flex; justify-content: center; align-items: flex-start; }
.phone-notch::after { content: ""; width: 42%; height: 6px; background: #0f1230; border-radius: 0 0 10px 10px; }
.pay-head { padding: .5rem 1.1rem .3rem; }
.pay-head .bank { font-size: .7rem; color: var(--neutral-500); font-weight: 600; }
.pay-body { padding: .4rem 1.1rem 1.1rem; display: flex; flex-direction: column; gap: .7rem; flex: 1; }
.pay-academy { display: flex; align-items: center; gap: .5rem; margin-top: .2rem; }
.pay-academy .ac-logo { width: 30px; height: 30px; border-radius: 9px; background: var(--grad-cta); display: grid; place-items: center; color: #fff; font-weight: 800; font-size: .8rem; }
.pay-academy .ac-name { font-weight: 700; font-size: .82rem; }
.pay-academy .ac-desc { font-size: .64rem; color: var(--neutral-500); }
.pay-amount-card {
  margin-top: .3rem; background: var(--surface-tint); border-radius: 16px; padding: .85rem .9rem;
  border: 1px solid var(--color-primary-50);
}
.pay-amount-card .label { font-size: .66rem; color: var(--neutral-500); font-weight: 600; }
.pay-amount-card .amount { font-size: 1.5rem; font-weight: 800; letter-spacing: -0.02em; margin-top: .1rem; font-variant-numeric: tabular-nums; }
.pay-amount-card .amount small { font-size: .8rem; font-weight: 700; }
.pay-line { display: flex; justify-content: space-between; font-size: .66rem; color: var(--neutral-500); padding: 0 .1rem; }
.pay-line b { color: var(--neutral-900); font-weight: 700; }
.pay-pay-btn {
  margin-top: auto; background: var(--grad-cta); color: #fff; text-align: center;
  padding: .8rem; border-radius: 14px; font-weight: 800; font-size: .9rem;
  box-shadow: var(--shadow-glow);
}
.pay-secure { display: flex; align-items: center; justify-content: center; gap: .3rem; font-size: .6rem; color: var(--neutral-500); margin-top: .5rem; }
.pay-secure svg { width: 11px; height: 11px; }

/* 결제 완료 글래스 말풍선 */
.pay-toast {
  position: absolute; z-index: 5; top: 16%; right: -14%;
  display: flex; align-items: center; gap: .55rem;
  background: var(--glass-bg); backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: 16px; padding: .7rem .95rem;
  box-shadow: var(--shadow-3);
  color: var(--neutral-900);
  animation: floatY 6s ease-in-out infinite .8s;
}
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .pay-toast { background: #fff; }
}
.pay-toast .check {
  width: 30px; height: 30px; border-radius: 50%; background: #16a34a;
  display: grid; place-items: center; color: #fff; font-weight: 800; flex: none;
}
.pay-toast .t-title { font-size: .8rem; font-weight: 800; }
.pay-toast .t-sub { font-size: .66rem; color: var(--neutral-500); }

@media (prefers-reduced-motion: reduce) {
  .hero .blob, .phone, .pay-toast { animation: none !important; }
}

/* ============================ PROBLEM (S2) ============================ */
.problem-grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.1rem;
}
.p-card {
  background: #fff; border: 1px solid var(--neutral-200); border-radius: var(--radius-lg);
  padding: 1.6rem 1.4rem; box-shadow: var(--shadow-2);
  transition: transform .25s ease, box-shadow .25s ease;
}
.p-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-3); }
.p-card .ic {
  width: 48px; height: 48px; border-radius: 14px; display: grid; place-items: center;
  font-size: 1.5rem; background: var(--color-secondary-50); margin-bottom: 1rem;
}
.p-card h3 { font-size: 1.06rem; font-weight: 700; }
.p-card p { margin-top: .5rem; font-size: .94rem; color: var(--neutral-700); }
.fact-strip {
  margin-top: 2.2rem; display: flex; flex-wrap: wrap; align-items: center; gap: .8rem 1.5rem;
  background: var(--hero-ink); color: #fff; border-radius: var(--radius-lg);
  padding: 1.3rem 1.6rem;
}
.fact-strip .fact { display: flex; align-items: center; gap: .6rem; font-weight: 600; }
.fact-strip .fact b { color: var(--color-secondary-400); font-weight: 800; }
.fact-strip .fact .ic { font-size: 1.3rem; }
.footnote { font-size: .8rem; color: var(--neutral-500); margin-top: 1rem; }
.footnote a { text-decoration: underline; text-underline-offset: 2px; }

/* ============================ CALCULATOR (S3) ============================ */
.calc-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(1.5rem, 3vw, 3rem); align-items: stretch; }
.calc-controls {
  background: #fff; border: 1px solid var(--neutral-200); border-radius: var(--radius-xl);
  padding: clamp(1.5rem, 3vw, 2.4rem); box-shadow: var(--shadow-2);
}
.slider-field { margin-bottom: 1.9rem; }
.slider-field:last-child { margin-bottom: 0; }
.slider-field .sf-top { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: .8rem; }
.slider-field label { font-weight: 700; font-size: 1rem; }
.slider-field .sf-val {
  font-weight: 800; font-size: 1.25rem; color: var(--color-primary-600);
  font-variant-numeric: tabular-nums;
}
.slider-field .sf-val small { font-size: .9rem; font-weight: 700; color: var(--neutral-500); }
input[type="range"] {
  -webkit-appearance: none; appearance: none; width: 100%; height: 8px;
  border-radius: 999px; background: var(--neutral-200); outline-offset: 4px;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none; width: 26px; height: 26px; border-radius: 50%;
  background: #fff; border: 3px solid var(--color-primary-600);
  box-shadow: var(--shadow-2); cursor: pointer; transition: transform .12s ease;
}
input[type="range"]::-webkit-slider-thumb:active { transform: scale(1.15); }
input[type="range"]::-moz-range-thumb {
  width: 26px; height: 26px; border-radius: 50%; background: #fff;
  border: 3px solid var(--color-primary-600); box-shadow: var(--shadow-2); cursor: pointer;
}
.slider-field .sf-scale { display: flex; justify-content: space-between; font-size: .76rem; color: var(--neutral-500); margin-top: .5rem; }

.calc-result {
  background: var(--grad-hero); color: #fff; border-radius: var(--radius-xl);
  padding: clamp(1.6rem, 3vw, 2.4rem); position: relative; overflow: hidden;
  box-shadow: var(--shadow-float);
  display: flex; flex-direction: column;
}
.calc-result::before {
  content: ""; position: absolute; width: 300px; height: 300px; border-radius: 50%;
  background: radial-gradient(circle, var(--blob-3), transparent 70%);
  top: -80px; right: -60px; filter: blur(20px);
}
.calc-result .cr-inner { position: relative; z-index: 1; display: flex; flex-direction: column; height: 100%; }
.calc-result .cr-label { font-size: .95rem; font-weight: 600; color: rgba(255,255,255,.82); }
.calc-result .cr-amount {
  font-size: var(--fs-stat); font-weight: 800; letter-spacing: -0.03em; line-height: 1.05;
  margin-top: .4rem; font-variant-numeric: tabular-nums; white-space: nowrap;
}
.calc-result .cr-amount .won { font-size: .55em; }
.calc-result .cr-sub { margin-top: .9rem; font-size: .98rem; color: rgba(255,255,255,.88); }
.calc-result .cr-sub b { color: var(--color-secondary-400); }
.calc-result .cr-caption { margin-top: 1rem; font-size: .82rem; color: rgba(255,255,255,.66); }
.calc-result .btn { margin-top: auto; }
.calc-result .btn-coral { margin-top: 1.4rem; }

/* ============================ SOLUTIONS (S4) ============================ */
.sol-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.3rem; }
.sol-card {
  background: #fff; border: 1px solid var(--neutral-200); border-radius: var(--radius-xl);
  padding: 2rem 1.7rem; box-shadow: var(--shadow-2);
  transition: transform .25s ease, box-shadow .25s ease;
}
.sol-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-3); }
.sol-card.accent { background: var(--color-secondary-50); border-color: var(--color-secondary-400); }
.sol-card .s-ic {
  width: 56px; height: 56px; border-radius: 16px; display: grid; place-items: center;
  font-size: 1.7rem; background: var(--color-primary-50); margin-bottom: 1.2rem;
}
.sol-card.accent .s-ic { background: #fff; }
.sol-card h3 { font-size: 1.22rem; font-weight: 800; letter-spacing: -0.01em; }
.sol-card p { margin-top: .7rem; font-size: .98rem; color: var(--neutral-700); }
.sol-note {
  margin-top: 1.6rem; text-align: center; font-size: .96rem; color: var(--neutral-700);
  background: var(--color-primary-50); border-radius: var(--radius-pill);
  padding: .85rem 1.4rem; display: inline-flex; align-items: center; gap: .5rem;
}
.sol-note-wrap { text-align: center; margin-top: 1.8rem; }

/* ============================ BEFORE/AFTER (S5) ============================ */
.ba-toggle {
  display: inline-flex; background: var(--neutral-200); border-radius: var(--radius-pill);
  padding: 5px; margin-bottom: 2rem; position: relative;
}
.ba-toggle button {
  padding: .65rem 1.6rem; border-radius: var(--radius-pill); font-weight: 700; font-size: .98rem;
  color: var(--neutral-700); position: relative; z-index: 1; transition: color .25s ease;
}
.ba-toggle button[aria-selected="true"] { color: #fff; }
.ba-toggle .thumb {
  position: absolute; z-index: 0; top: 5px; bottom: 5px; border-radius: var(--radius-pill);
  background: var(--grad-cta); box-shadow: var(--shadow-glow);
  transition: transform .3s cubic-bezier(.4,0,.2,1), width .3s ease;
}
.ba-list { display: grid; gap: .8rem; max-width: 760px; }
.ba-row {
  display: grid; grid-template-columns: 44px 1fr; gap: 1rem; align-items: center;
  background: #fff; border: 1px solid var(--neutral-200); border-radius: 16px;
  padding: 1.1rem 1.3rem; box-shadow: var(--shadow-2);
}
.ba-row .r-ic {
  width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center;
  font-size: 1.3rem; font-weight: 800; flex: none;
  transition: background-color .3s ease, color .3s ease;
}
.ba-row .r-text { font-size: 1.02rem; font-weight: 600; transition: color .2s ease; }
.ba-panel[data-state="before"] .r-ic { background: var(--color-secondary-50); color: var(--color-secondary-500); }
.ba-panel[data-state="after"] .r-ic { background: #e6f7ec; color: #16a34a; }
.ba-panel { position: relative; }
.ba-fade { animation: fadeSwap .35s ease; }
@keyframes fadeSwap { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }
@media (prefers-reduced-motion: reduce) { .ba-fade { animation: none; } .ba-toggle .thumb { transition: none; } }

/* ============================ DEMO TABS (S6) ============================ */
.demo-tabs { display: flex; flex-wrap: wrap; gap: .5rem; margin-bottom: 1.8rem; }
.demo-tabs button {
  padding: .7rem 1.3rem; border-radius: var(--radius-pill); font-weight: 700; font-size: .96rem;
  color: var(--neutral-700); background: #fff; border: 1.5px solid var(--neutral-200);
  transition: all .2s ease;
}
.demo-tabs button[aria-selected="true"] {
  color: #fff; background: var(--grad-cta); border-color: transparent; box-shadow: var(--shadow-glow);
}
.demo-stage {
  background: var(--hero-ink); border-radius: var(--radius-xl); padding: clamp(1.2rem, 3vw, 2.4rem);
  box-shadow: var(--shadow-float); position: relative; overflow: hidden;
}
.demo-stage::before {
  content: ""; position: absolute; width: 340px; height: 340px; border-radius: 50%;
  background: radial-gradient(circle, var(--blob-2), transparent 70%); top: -120px; left: -60px; filter: blur(20px);
}
.demo-panel { position: relative; z-index: 1; display: none; }
.demo-panel[data-active="true"] { display: block; animation: fadeSwap .35s ease; }
@media (prefers-reduced-motion: reduce) { .demo-panel[data-active="true"] { animation: none; } }
.mock {
  background: #fff; border-radius: 16px; overflow: hidden; box-shadow: var(--shadow-3);
  color: var(--neutral-900);
}
.mock-head { display: flex; align-items: center; gap: .5rem; padding: .8rem 1.1rem; border-bottom: 1px solid var(--neutral-200); }
.mock-head .dots { display: flex; gap: 6px; }
.mock-head .dots i { width: 10px; height: 10px; border-radius: 50%; display: block; }
.mock-head .dots i:nth-child(1){background:#ff5f57;} .mock-head .dots i:nth-child(2){background:#febc2e;} .mock-head .dots i:nth-child(3){background:#28c840;}
.mock-head .m-title { font-size: .82rem; font-weight: 700; color: var(--neutral-500); }
.mock-body { padding: 1.2rem; }
.demo-caption { color: rgba(255,255,255,.85); margin-top: 1.2rem; font-size: .98rem; display: flex; flex-wrap: wrap; align-items: center; gap: .8rem 1.2rem; justify-content: space-between; position: relative; z-index: 1; }
.demo-caption .btn { min-height: 46px; }

/* mock: dashboard */
.kpi-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: .8rem; margin-bottom: 1.1rem; }
.kpi { background: var(--surface-b); border-radius: 12px; padding: .9rem 1rem; }
.kpi .k-label { font-size: .74rem; color: var(--neutral-500); font-weight: 600; }
.kpi .k-val { font-size: 1.3rem; font-weight: 800; margin-top: .2rem; font-variant-numeric: tabular-nums; }
.kpi .k-val.coral { color: var(--color-secondary-500); }
.list-row { display: flex; align-items: center; justify-content: space-between; padding: .7rem .2rem; border-bottom: 1px solid var(--neutral-200); font-size: .9rem; }
.list-row:last-child { border-bottom: none; }
.pill-status { font-size: .74rem; font-weight: 700; padding: .2rem .6rem; border-radius: 999px; }
.pill-status.overdue { background: var(--color-secondary-50); color: var(--color-secondary-500); }
.pill-status.sent { background: var(--color-primary-50); color: var(--color-primary-600); }
.pill-status.paid { background: #e6f7ec; color: #16a34a; }
/* mock: send link */
.chat-mock { display: grid; gap: .7rem; }
.bubble { max-width: 82%; padding: .75rem 1rem; border-radius: 16px; font-size: .9rem; }
.bubble.out { background: var(--color-primary-600); color: #fff; margin-left: auto; border-bottom-right-radius: 5px; }
.bubble.in { background: var(--surface-b); border-bottom-left-radius: 5px; }
.bubble .link-card { background: rgba(255,255,255,.16); border-radius: 10px; padding: .5rem .7rem; margin-top: .5rem; font-size: .82rem; }
.bubble.out .amt { font-weight: 800; }
/* mock: tax report */
.report-row { display: grid; grid-template-columns: 1fr auto auto; gap: 1rem; padding: .7rem .2rem; border-bottom: 1px solid var(--neutral-200); font-size: .9rem; align-items: center; }
.report-row.head { font-weight: 700; color: var(--neutral-500); font-size: .78rem; }
.report-row .num { font-variant-numeric: tabular-nums; font-weight: 700; }

/* ============================ STATS (S7) ============================ */
.stats-band { background: var(--hero-ink); color: #fff; position: relative; overflow: hidden; }
.stats-band::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(60% 100% at 20% 0%, rgba(74,96,232,.4), transparent 60%),
              radial-gradient(50% 90% at 90% 100%, rgba(245,100,60,.22), transparent 60%);
}
.stats-band .container { position: relative; z-index: 1; }
.stats-head { text-align: center; margin-bottom: 3rem; }
.stats-head h2 { font-size: var(--fs-display); font-weight: 800; letter-spacing: -0.02em; }
.stats-head p { color: rgba(255,255,255,.75); margin-top: .8rem; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; }
.stat {
  text-align: center; padding: 1.4rem 1rem; border-radius: var(--radius-lg);
  background: rgba(255,255,255,.05); border: 1px solid rgba(255,255,255,.1);
}
.stat .s-num {
  font-size: var(--fs-stat); font-weight: 800; letter-spacing: -0.02em; line-height: 1;
  font-variant-numeric: tabular-nums; white-space: nowrap;
  background: linear-gradient(180deg,#fff,#c9d2ff); -webkit-background-clip: text; background-clip: text; color: transparent;
}
.stat .s-num .unit { font-size: .5em; -webkit-text-fill-color: rgba(255,255,255,.9); }
.stat .s-label { margin-top: .7rem; font-weight: 700; font-size: 1rem; }
.stat .s-src { margin-top: .5rem; font-size: .74rem; color: rgba(255,255,255,.55); }

/* ============================ PRICING SIM (S8) ============================ */
.sim-wrap { display: grid; grid-template-columns: 1fr .9fr; gap: clamp(1.5rem,3vw,3rem); align-items: stretch; }
.sim-controls { background: #fff; border: 1px solid var(--neutral-200); border-radius: var(--radius-xl); padding: clamp(1.5rem,3vw,2.4rem); box-shadow: var(--shadow-2); }
.sim-module {
  display: flex; align-items: center; gap: 1rem; padding: 1.05rem 0; border-bottom: 1px solid var(--neutral-200);
}
.sim-module:last-of-type { border-bottom: none; }
.sim-module .m-info { flex: 1; }
.sim-module .m-name { font-weight: 700; font-size: 1.02rem; display: flex; align-items: center; gap: .4rem; }
.sim-module .m-price { font-size: .86rem; color: var(--neutral-500); margin-top: .2rem; font-variant-numeric: tabular-nums; }
.sim-module .m-price .tag-assume { color: var(--color-primary-600); font-weight: 700; }
.info-tip { position: relative; display: inline-flex; }
.info-tip button { width: 18px; height: 18px; border-radius: 50%; background: var(--neutral-200); color: var(--neutral-700); font-size: .7rem; font-weight: 800; display: grid; place-items: center; min-width: 18px; min-height: 18px; }
.info-tip .tip-body {
  position: absolute; bottom: calc(100% + 8px); left: 50%; transform: translateX(-50%);
  background: var(--neutral-900); color: #fff; padding: .6rem .8rem; border-radius: 10px;
  font-size: .78rem; font-weight: 500; width: max-content; max-width: 220px; line-height: 1.45;
  opacity: 0; visibility: hidden; transition: opacity .2s ease; box-shadow: var(--shadow-3); z-index: 5;
}
.info-tip .tip-body::after { content: ""; position: absolute; top: 100%; left: 50%; transform: translateX(-50%); border: 6px solid transparent; border-top-color: var(--neutral-900); }
.info-tip:hover .tip-body, .info-tip button:focus-visible + .tip-body { opacity: 1; visibility: visible; }

/* switch */
.switch { position: relative; width: 52px; height: 30px; flex: none; }
.switch input { position: absolute; opacity: 0; width: 100%; height: 100%; margin: 0; cursor: pointer; }
.switch .track { position: absolute; inset: 0; background: var(--neutral-200); border-radius: 999px; transition: background-color .25s ease; }
.switch .track::after { content: ""; position: absolute; top: 3px; left: 3px; width: 24px; height: 24px; border-radius: 50%; background: #fff; box-shadow: var(--shadow-2); transition: transform .25s ease; }
.switch input:checked + .track { background: var(--color-primary-600); }
.switch input:checked + .track::after { transform: translateX(22px); }
.switch input:disabled + .track { background: var(--color-primary-600); opacity: .55; }
.switch input:focus-visible + .track { outline: 3px solid var(--color-primary-500); outline-offset: 2px; }
.sim-module.locked .m-name::after { content: "기본 포함"; font-size: .68rem; font-weight: 700; color: var(--color-primary-600); background: var(--color-primary-50); padding: .12rem .5rem; border-radius: 999px; }

.sim-students { margin-top: 1.4rem; }
.sim-result {
  background: var(--grad-hero); color: #fff; border-radius: var(--radius-xl);
  padding: clamp(1.6rem,3vw,2.4rem); box-shadow: var(--shadow-float);
  position: relative; overflow: hidden; display: flex; flex-direction: column;
}
.sim-result::before { content:""; position:absolute; width:280px; height:280px; border-radius:50%; background:radial-gradient(circle,var(--blob-2),transparent 70%); bottom:-90px; right:-70px; filter:blur(20px); }
.sim-result .sr-in { position: relative; z-index: 1; display: flex; flex-direction: column; height: 100%; }
.free-badge {
  display: inline-flex; align-items: center; gap: .4rem; align-self: flex-start;
  background: var(--grad-coral); color: #fff; font-weight: 800; font-size: .84rem;
  padding: .4rem .9rem; border-radius: 999px; box-shadow: 0 6px 18px rgba(245,100,60,.4);
}
.sim-result .sr-label { font-size: .95rem; color: rgba(255,255,255,.82); margin-top: 1.2rem; }
.sim-result .sr-amount { font-size: var(--fs-stat); font-weight: 800; letter-spacing: -0.02em; margin-top: .3rem; font-variant-numeric: tabular-nums; white-space: nowrap; }
.sim-result .sr-amount .won { font-size: .5em; }
.sim-result .sr-amount .per { font-size: .32em; font-weight: 700; color: rgba(255,255,255,.7); }
.sim-result .sr-anchor { margin-top: .9rem; font-size: .92rem; color: rgba(255,255,255,.85); }
.sim-result .sr-caption { margin-top: .8rem; font-size: .8rem; color: rgba(255,255,255,.62); }
.sim-result .btn { margin-top: auto; }
.sim-result .btn-coral { margin-top: 1.4rem; }

/* ============================ TRUST / FAQ (S9) ============================ */
.trust-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: clamp(1.5rem,3vw,3rem); align-items: start; }
.faq-item { border: 1px solid var(--neutral-200); border-radius: 16px; background: #fff; margin-bottom: .8rem; overflow: hidden; box-shadow: var(--shadow-2); }
.faq-q {
  width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 1rem;
  padding: 1.2rem 1.4rem; font-weight: 700; font-size: 1.04rem; text-align: left;
}
.faq-q .chev { flex: none; transition: transform .3s ease; color: var(--color-primary-600); font-size: 1.2rem; }
.faq-q[aria-expanded="true"] .chev { transform: rotate(180deg); }
.faq-a { overflow: hidden; height: 0; transition: height .3s ease; }
.faq-a-inner { padding: 0 1.4rem 1.3rem; color: var(--neutral-700); font-size: .98rem; }
@media (prefers-reduced-motion: reduce) { .faq-a { transition: none; } .faq-q .chev { transition: none; } }

.badge-stack { display: grid; gap: .9rem; }
.trust-badge {
  display: flex; align-items: flex-start; gap: .9rem;
  background: var(--surface-b); border: 1px solid var(--neutral-200); border-radius: 16px; padding: 1.1rem 1.2rem;
}
.trust-badge .b-ic { width: 42px; height: 42px; border-radius: 12px; background: #fff; display: grid; place-items: center; font-size: 1.3rem; flex: none; box-shadow: var(--shadow-2); }
.trust-badge .b-title { font-weight: 800; font-size: 1rem; }
.trust-badge .b-desc { font-size: .88rem; color: var(--neutral-700); margin-top: .25rem; }

/* ============================ FINAL CTA (S10) ============================ */
.final-cta { background: var(--grad-hero); color: #fff; text-align: center; position: relative; overflow: hidden; }
.final-cta::before { content:""; position:absolute; inset:0; background: radial-gradient(50% 120% at 50% 0%, rgba(255,138,107,.28), transparent 60%); }
.final-cta .container { position: relative; z-index: 1; }
.final-cta h2 { font-size: var(--fs-display); font-weight: 800; letter-spacing: -0.02em; max-width: 18em; margin-inline: auto; }
.final-cta .fc-btns { display: flex; flex-wrap: wrap; gap: .8rem; justify-content: center; margin-top: 2rem; }
.final-cta .fc-badges { margin-top: 1.5rem; font-size: .95rem; color: rgba(255,255,255,.85); }
.final-cta .fc-refer { margin-top: 1rem; font-size: .88rem; color: rgba(255,255,255,.7); }

/* ============================ FOOTER (S11) ============================ */
.site-footer { background: var(--neutral-900); color: rgba(255,255,255,.7); padding-block: clamp(2.5rem,4vw,3.5rem) 2rem; }
.footer-top { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 2rem; }
.footer-brand { max-width: 30em; }
.footer-brand .brand { color: #fff; margin-bottom: .8rem; }
.footer-brand p { font-size: .92rem; line-height: 1.7; }
.footer-links { display: flex; gap: 2.5rem; flex-wrap: wrap; }
.footer-col h4 { color: #fff; font-size: .92rem; margin-bottom: .9rem; }
.footer-col a, .footer-col span { display: block; font-size: .88rem; padding: .25rem 0; color: rgba(255,255,255,.62); }
.footer-col a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.12); margin-top: 2.5rem; padding-top: 1.5rem; font-size: .82rem; color: rgba(255,255,255,.5); display: flex; flex-wrap: wrap; justify-content: space-between; gap: 1rem; }

/* ============================ MOBILE STICKY CTA ============================ */
.mobile-cta {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 90;
  display: none; gap: .6rem; padding: .7rem clamp(.9rem,4vw,1.2rem);
  padding-bottom: max(.7rem, env(safe-area-inset-bottom));
  background: var(--glass-bg); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
  border-top: 1px solid var(--neutral-200); box-shadow: 0 -4px 20px rgba(34,32,29,.1);
}
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .mobile-cta { background: #fff; }
}
.mobile-cta .btn { flex: 1; min-height: 50px; }

/* ============================ SCROLL REVEAL ============================ */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; will-change: opacity, transform; }
.reveal.in { opacity: 1; transform: none; }
.reveal[data-delay="1"] { transition-delay: .08s; }
.reveal[data-delay="2"] { transition-delay: .16s; }
.reveal[data-delay="3"] { transition-delay: .24s; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1 !important; transform: none !important; transition: none !important; }
}

/* ============================ RESPONSIVE ============================ */
@media (max-width: 960px) {
  .hero-grid { grid-template-columns: 1fr; text-align: center; }
  .hero-copy .eyebrow { align-self: center; }
  .hero-sub { margin-inline: auto; }
  .hero-cta, .friction-badges { justify-content: center; }
  .hero-visual { margin-top: 2.5rem; }
  .problem-grid { grid-template-columns: repeat(2, 1fr); }
  .calc-wrap, .sim-wrap, .trust-grid { grid-template-columns: 1fr; }
  .sol-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .nav-links, .header-cta .btn-desktop { display: none; }
  .nav-toggle { display: flex; }
  .kpi-row { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 640px) {
  .mobile-cta { display: flex; }
  body { padding-bottom: 76px; }
  .site-footer, .final-cta { }
  .problem-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .fact-strip { flex-direction: column; align-items: flex-start; }
  .footer-top { flex-direction: column; }
  .demo-caption { flex-direction: column; align-items: flex-start; }
  .kpi-row { grid-template-columns: 1fr; }
  .btn { width: 100%; }
  .hero-cta .btn, .fc-btns .btn { width: auto; }
}
@media (max-width: 400px) {
  .calc-result .cr-amount, .sim-result .sr-amount, .stat .s-num { font-size: clamp(1.9rem, 9vw, 2.4rem); }
}

/* --- mobile nav drawer --- */
.mobile-nav {
  position: fixed; inset: 0; z-index: 150; display: none;
}
.mobile-nav[data-open="true"] { display: block; }
.mobile-nav .backdrop { position: absolute; inset: 0; background: rgba(23,30,92,.5); backdrop-filter: blur(2px); }
.mobile-nav .panel {
  position: absolute; top: 0; right: 0; bottom: 0; width: min(320px, 84vw);
  background: #fff; box-shadow: var(--shadow-3); padding: 1.5rem;
  display: flex; flex-direction: column; gap: .3rem;
  transform: translateX(100%); transition: transform .3s ease;
}
.mobile-nav[data-open="true"] .panel { transform: none; }
@media (prefers-reduced-motion: reduce) { .mobile-nav .panel { transition: none; } }
.mobile-nav .panel .m-close { align-self: flex-end; width: 44px; height: 44px; font-size: 1.5rem; border-radius: 10px; color: var(--neutral-700); }
.mobile-nav .panel a { padding: .9rem .6rem; font-weight: 700; font-size: 1.1rem; border-radius: 10px; }
.mobile-nav .panel a:hover { background: var(--color-primary-50); }
.mobile-nav .panel .btn { margin-top: 1rem; }