/* ============================================================
   BM4M — Mono Ink (흑백) brand site
   순수 CSS. 포인트 컬러 없음. 색과 온기는 히어로 영상이 담당.
   ============================================================ */

/* ---------- Design Tokens ---------- */
:root {
  --bg:        #FFFFFF;
  --bg-soft:   #F5F4F2;            /* 섹션 교차용 따뜻한 화이트 */
  --ink:       #0A0A0A;           /* 주조·텍스트 */
  --ink-2:     #6B6B6B;           /* 보조 텍스트 */
  --line:      #E5E4E1;           /* 구분선 */
  --on-dark:   #FFFFFF;           /* 영상 위 흰 글씨 */
  --on-dark-2: rgba(255, 255, 255, 0.82);

  --font: "Pretendard", -apple-system, BlinkMacSystemFont,
          "Apple SD Gothic Neo", system-ui, sans-serif;

  --header-h: 72px;
  --maxw: 1200px;
  --pad-x: clamp(1.25rem, 5vw, 4rem);
}

/* ---------- Reset / Base ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--ink);
  font-size: 19px;          /* 데스크탑 기본 */
  line-height: 1.75;        /* 여유있는 줄간격 */
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

@media (max-width: 720px) {
  body { font-size: 16px; line-height: 1.7; } /* 모바일 기본 */
}

img, video { display: block; max-width: 100%; }

a { color: inherit; text-decoration: none; }

h1, h2, p { margin: 0; }

/* 키보드 포커스 표시 유지 */
:focus-visible {
  outline: 2px solid currentColor;
  outline-offset: 4px;
  border-radius: 2px;
}

/* ============================================================
   HEADER (고정 / transparent)
   ============================================================ */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--pad-x);
  color: var(--on-dark);
  transition: background 0.35s ease, color 0.35s ease,
    box-shadow 0.35s ease, transform 0.35s ease;
}

/* 스크롤 시: 반투명 + 블러 + 잉크 텍스트 */
.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.78);
  backdrop-filter: blur(12px) saturate(1.1);
  -webkit-backdrop-filter: blur(12px) saturate(1.1);
  color: var(--ink);
  box-shadow: 0 1px 0 var(--line);
}

.site-header.is-scrolled .nav a { color: var(--ink-2); }
.site-header.is-scrolled .nav a:hover,
.site-header.is-scrolled .nav a.is-active { color: var(--ink); }

/* 아래로 스크롤 시 헤더 숨김, 위로 스크롤 시 노출 */
.site-header.is-hidden { transform: translateY(-100%); }

/* 현재 섹션 표시 (밑줄) */
.nav a {
  position: relative;
}
.nav a.is-active::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -6px;
  height: 1px;
  background: currentColor;
}

.wordmark {
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: 0.04em;
}

.nav {
  display: flex;
  gap: clamp(1.25rem, 3vw, 2.5rem);
}

.nav a {
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--on-dark-2);
  transition: color 0.25s ease;
}

.nav a:hover { color: var(--on-dark); }

/* 햄버거 버튼 (데스크탑 숨김) */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 0;
  background: none;
  border: 0;
  cursor: pointer;
  color: inherit;
}

.nav-toggle__bar {
  display: block;
  width: 24px;
  height: 2px;
  margin: 0 auto;
  background: currentColor;
  transition: transform 0.3s ease, opacity 0.2s ease;
}

/* 열림 상태 → X 모양 */
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* 모바일: nav → 풀스크린 드로어 */
@media (max-width: 720px) {
  .nav-toggle { display: flex; }

  .nav {
    position: fixed;
    inset: 0;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: clamp(1.5rem, 6vh, 3rem);
    background: var(--ink);
    color: var(--on-dark);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.4s cubic-bezier(0.22, 1, 0.36, 1), opacity 0.3s ease;
  }

  .nav.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav a {
    font-size: 1.25rem;
    letter-spacing: 0.12em;
    color: var(--on-dark);
  }
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative;
  width: 100%;
  height: 100vh;          /* 폴백 */
  height: 100svh;
  min-height: 540px;
  overflow: hidden;
  background: var(--ink); /* 영상 로딩 전 검정 */
  display: flex;
  align-items: flex-end;  /* 카피 좌하단 정렬 */
}

.hero__video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  /* 영상 톤 보정 (모노 UI와 조화) */
  filter: saturate(0.9) brightness(0.85);
  /* 가장자리 크롭 → 우하단 AI 워터마크(✦) 화면 밖으로 밀어냄 */
  transform: scale(1.08);
  transform-origin: 18% 22%; /* 우하단을 더 잘라내도록 기준점을 좌상단 쪽으로 */
}

/* 우하단 워터마크 차단 레이어 (코너 한정 그라데이션 + 블러) */
.hero__corner-mask {
  position: absolute;
  right: 0;
  bottom: 0;
  width: clamp(120px, 22vw, 260px);
  height: clamp(80px, 16vh, 180px);
  z-index: 1;
  pointer-events: none;
  background: radial-gradient(
    120% 120% at 100% 100%,
    rgba(10, 10, 10, 0.92) 0%,
    rgba(10, 10, 10, 0.55) 45%,
    transparent 75%
  );
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  -webkit-mask-image: radial-gradient(120% 120% at 100% 100%, #000 40%, transparent 75%);
  mask-image: radial-gradient(120% 120% at 100% 100%, #000 40%, transparent 75%);
}

/* 오버레이 1: 전체 톤 (가독성) */
.hero__overlay {
  position: absolute;
  inset: 0;
  background: rgba(10, 10, 10, 0.35);
}

/* 오버레이 2: 하단 그라데이션 (워터마크 가림 + 스크롤 표시 안착) */
.hero__gradient {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to bottom,
    transparent 55%,
    rgba(10, 10, 10, 0.85) 100%
  );
}

.hero__copy {
  position: relative;
  z-index: 2;
  padding: 0 var(--pad-x) clamp(4.5rem, 12vh, 8rem);
  max-width: 900px;
}

.hero__title {
  color: var(--on-dark);
  font-size: clamp(2.5rem, 7vw, 6rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.05;
}

.hero__sub {
  margin-top: clamp(0.75rem, 2vh, 1.25rem);
  color: var(--on-dark-2);
  font-size: clamp(0.95rem, 2.5vw, 1.15rem);
  font-weight: 400;
}

/* 흰 테두리 CTA (히어로 전용) */
.hero__cta {
  display: inline-block;
  margin-top: clamp(1.5rem, 4vh, 2.25rem);
  padding: 0.85em 1.6em;
  border: 1px solid var(--on-dark);
  color: var(--on-dark);
  font-size: clamp(0.85rem, 2vw, 0.95rem);
  font-weight: 500;
  letter-spacing: 0.04em;
  transition: background 0.25s ease, color 0.25s ease;
}

.hero__cta:hover {
  background: var(--on-dark);
  color: var(--ink);
}

/* 스크롤 유도 (하단 중앙) */
.hero__scroll {
  position: absolute;
  z-index: 2;
  left: 50%;
  bottom: clamp(1.5rem, 4vh, 2.5rem);
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
  color: var(--on-dark-2);
}

.hero__scroll-label {
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.22em;
}

.hero__scroll-arrow {
  font-size: 1rem;
  line-height: 1;
  animation: scroll-bounce 2s ease-in-out infinite;
}

@keyframes scroll-bounce {
  0%, 100% { transform: translateY(0); opacity: 0.7; }
  50%      { transform: translateY(6px); opacity: 1; }
}

/* ---------- 로드 모션 (히어로 카피) ---------- */
.load-up {
  opacity: 0;
  transform: translateY(16px);
  animation: load-up 0.8s cubic-bezier(0.22, 1, 0.36, 1) forwards;
  animation-delay: var(--delay, 0s);
}

@keyframes load-up {
  to { opacity: 1; transform: translateY(0); }
}

/* ============================================================
   SECTION 공통 레이아웃
   ============================================================ */
.section {
  padding: clamp(5.75rem, 16vh, 10.5rem) var(--pad-x);
  background: var(--bg);
}

.section--soft { background: var(--bg-soft); }

.section--dark {
  background: var(--ink);
  color: var(--on-dark);
}

.section__inner {
  max-width: var(--maxw);
  margin: 0 auto;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 0.7em;
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.24em;
  color: var(--ink-2);
  margin-bottom: 1.15rem;
}

/* 에디토리얼 룰 라인 (eyebrow 앞 짧은 선) */
.eyebrow::before {
  content: "";
  width: 28px;
  height: 1px;
  background: currentColor;
  opacity: 0.55;
}

.section--dark .eyebrow { color: var(--on-dark-2); }

.section__headline {
  font-size: clamp(2.6rem, 7vw, 5rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.08;
}

.section__sub {
  margin-top: 0.9rem;
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: var(--ink-2);
}

.section--dark .section__sub { color: var(--on-dark-2); }

.section__lead {
  margin-top: 1.25rem;
  max-width: 46ch;
  font-size: clamp(1.1rem, 2.3vw, 1.35rem);
  line-height: 1.6;
  color: var(--ink-2);
}

/* ============================================================
   모바일: 섹션 패딩 축소(약 60~65%) → 휑함 제거, 밀도 ↑
   ============================================================ */
@media (max-width: 720px) {
  .section { padding: 3.5rem var(--pad-x); }
}

/* ============================================================
   WHY — 3컬럼 카드
   ============================================================ */
.cards {
  margin-top: clamp(2.5rem, 6vh, 4rem);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(1.5rem, 3vw, 2.5rem);
}

.card {
  padding: clamp(1.75rem, 3vw, 2.5rem);
  background: var(--bg);
  border: 1px solid var(--line);
}

.card__num {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--ink-2);
}

.card__title {
  margin-top: 0.75rem;
  font-size: clamp(1.3rem, 2.6vw, 1.6rem);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.card__desc {
  margin-top: 0.65rem;
  color: var(--ink-2);
  font-size: 1.05rem;
  line-height: 1.6;
}

@media (max-width: 720px) {
  .cards { grid-template-columns: 1fr; }
}

/* ============================================================
   STATS — 숫자 지표 (카운트업)
   ============================================================ */
.stats__grid {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: clamp(2rem, 4vw, 3rem);
  text-align: center;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.6rem;
}

.stat__num {
  margin: 0;
  font-size: clamp(2.75rem, 7vw, 5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

.stat__label {
  font-size: clamp(0.85rem, 1.6vw, 1rem);
  color: var(--ink-2);
  letter-spacing: 0.01em;
}

/* 검정 풀블리드 STATS: 흰 숫자 */
.stats.section--dark .stat__num { color: var(--on-dark); }
.stats.section--dark .stat__label { color: var(--on-dark-2); }

@media (max-width: 720px) {
  .stats__grid { grid-template-columns: repeat(2, 1fr); gap: 2.25rem 1.25rem; }
}

/* ============================================================
   FAQ — 아코디언
   ============================================================ */
.section__inner--narrow { max-width: 820px; }

.faq {
  margin-top: clamp(2.5rem, 6vh, 4rem);
  border-top: 1px solid var(--line);
}

.faq__item {
  border-bottom: 1px solid var(--line);
}

.faq__q { margin: 0; }

.faq__trigger {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: clamp(1.25rem, 3vw, 1.75rem) 0;
  background: none;
  border: 0;
  cursor: pointer;
  text-align: left;
  font-family: inherit;
  font-size: clamp(1.05rem, 2.2vw, 1.25rem);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.faq__trigger:hover { color: var(--ink-2); }

/* +/− 아이콘 */
.faq__icon {
  position: relative;
  flex: 0 0 18px;
  width: 18px;
  height: 18px;
}
.faq__icon::before,
.faq__icon::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 14px;
  height: 2px;
  background: currentColor;
  transform: translate(-50%, -50%);
  transition: transform 0.3s ease, opacity 0.3s ease;
}
.faq__icon::after { transform: translate(-50%, -50%) rotate(90deg); }

/* 열림: 세로획 숨겨 − 모양 */
.faq__trigger[aria-expanded="true"] .faq__icon::after {
  transform: translate(-50%, -50%) rotate(0);
  opacity: 0;
}

.faq__panel {
  height: 0;
  overflow: hidden;
  transition: height 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

.faq__a {
  margin: 0;
  padding: 0 0 clamp(1.25rem, 3vw, 1.75rem);
  max-width: 64ch;
  color: var(--ink-2);
  font-size: clamp(1rem, 2vw, 1.1rem);
  line-height: 1.7;
}

/* ============================================================
   PRODUCTS — 카테고리 그룹 + 제품 카드
   ============================================================ */
.product-group {
  margin-top: clamp(3rem, 7vh, 4.5rem);
}

/* 잡지풍 카테고리 헤더: 인덱스 + 큰 영문 + 한글 보조 + 룰 라인 */
.group-head {
  display: flex;
  align-items: baseline;
  gap: clamp(0.75rem, 2vw, 1.25rem);
  padding-bottom: clamp(0.85rem, 2vw, 1.15rem);
  border-bottom: 2px solid var(--ink);
}

.group-head__idx {
  font-size: clamp(0.85rem, 1.5vw, 1rem);
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--ink-2);
}

.group-head__title {
  margin: 0;
  font-size: clamp(1.75rem, 5vw, 2.5rem);  /* 모바일 ~28px, 데스크탑 40px */
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1;
}

.group-head__sub {
  margin-left: auto;
  font-size: clamp(0.9rem, 1.8vw, 1.05rem);
  color: var(--ink-2);
}

.products {
  margin-top: clamp(1.5rem, 3vh, 2rem);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(1.25rem, 2.5vw, 2rem) clamp(1.25rem, 2.5vw, 2rem);
}

/* 2개짜리 그룹(FASHION): 카드 크기 통일감 위해 2열 + 폭 제한 */
.products--two {
  grid-template-columns: repeat(2, 1fr);
  max-width: 800px;
}

.product {
  display: flex;
  flex-direction: column;
  transition: transform 0.25s ease;
}

.product:hover { transform: translateY(-4px); }

.product__thumb {
  display: block;
  position: relative;
  aspect-ratio: 4 / 3;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  margin-bottom: 1rem;
  overflow: hidden;
  transition: box-shadow 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

/* hover 시 부드럽게 떠오르는 모노 그림자 (절제된 강도) */
.product:hover .product__thumb {
  box-shadow: 0 18px 38px -20px rgba(10, 10, 10, 0.38);
}

.product__thumb img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s cubic-bezier(0.22, 1, 0.36, 1),
    opacity 0.45s ease;
}

/* 로드 페이드인 (JS 있을 때만 숨김 → 점진적 향상) */
.js .product__thumb img { opacity: 0; }
.js .product__thumb img.is-loaded { opacity: 1; }

.product:hover .product__thumb img { transform: scale(1.04); }

.product__name {
  display: inline-block;
  font-size: 1.25rem;      /* 20px */
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.4;
  background-image: linear-gradient(currentColor, currentColor);
  background-size: 0% 1px;
  background-position: 0 100%;
  background-repeat: no-repeat;
  transition: background-size 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

/* hover 시 제품명 밑줄 라인 등장 */
.product:hover .product__name { background-size: 100% 1px; }

.product__desc {
  margin-top: 0.5rem;
  color: var(--ink-2);
  font-size: 1rem;         /* 16px */
  line-height: 1.6;
}

@media (max-width: 980px) {
  .products { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 560px) {
  .products {
    grid-template-columns: 1fr;
    gap: 2rem;             /* 모바일 카드 세로 간격 (밀도 ↑) */
  }
}

/* ============================================================
   PARTNERSHIP — 검정 반전 대형 메시지
   ============================================================ */
.statement {
  margin-top: clamp(1.5rem, 4vh, 2.5rem);
  font-size: clamp(2.4rem, 8vw, 5.5rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.05;
  max-width: 16ch;
}

.statement__list {
  margin: clamp(2.5rem, 6vh, 4rem) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 1rem;
  max-width: 60ch;
}

.statement__list li {
  position: relative;
  padding-left: 1.5rem;
  font-size: clamp(1rem, 2.2vw, 1.2rem);
  color: var(--on-dark-2);
}

.statement__list li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--on-dark);
}

/* ============================================================
   PROCESS — 4단계 타임라인
   ============================================================ */
.timeline {
  margin: clamp(2.5rem, 6vh, 4rem) 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: clamp(1.5rem, 3vw, 2.5rem);
  counter-reset: step;
}

.step {
  padding-top: 1.5rem;
  border-top: 2px solid var(--ink);
}

.step__num {
  display: block;
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--ink-2);
}

.step__title {
  margin-top: 0.75rem;
  font-size: clamp(1.1rem, 2.5vw, 1.35rem);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.step__desc {
  margin-top: 0.5rem;
  color: var(--ink-2);
  font-size: 0.95rem;
}

@media (max-width: 860px) {
  .timeline { grid-template-columns: 1fr; gap: 0; }
  .step {
    border-top: 0;
    border-left: 2px solid var(--ink);
    padding: 0 0 2rem 1.5rem;
  }
  .step:last-child { padding-bottom: 0; }
}

/* ============================================================
   CONTACT — 강조 박스 + 버튼
   ============================================================ */
.btn {
  display: inline-block;
  padding: 0.9em 1.8em;
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  text-align: center;
  transition: background 0.25s ease, color 0.25s ease, opacity 0.25s ease;
}

.btn--fill {
  background: var(--ink);
  color: var(--on-dark);
  border: 1px solid var(--ink);
}

.btn--fill:hover { opacity: 0.85; }

.btn--outline {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--ink);
}

.btn--outline:hover { background: var(--ink); color: var(--on-dark); }

.contact-box {
  margin-top: clamp(2rem, 5vh, 3rem);
  padding: clamp(2rem, 5vw, 3.5rem);
  background: var(--bg);
  border: 1px solid var(--line);
  max-width: 620px;
}

.contact-box__title {
  font-size: clamp(1.2rem, 3vw, 1.5rem);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.contact-box__list {
  margin: 1.5rem 0 2rem;
  display: grid;
  gap: 0.75rem;
}

.contact-box__list div {
  display: flex;
  gap: 1rem;
  align-items: baseline;
}

.contact-box__list dt {
  flex: 0 0 5.5rem;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--ink-2);
}

.contact-box__list dd {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 500;
}

.contact-box__list a:hover { text-decoration: underline; }

.contact-note {
  margin-top: clamp(1.5rem, 4vh, 2rem);
  font-size: 0.9rem;
  color: var(--ink-2);
}

.contact-note a:hover { text-decoration: underline; }

/* ============================================================
   FOOTER (검정)
   ============================================================ */
.footer {
  background: var(--ink);
  color: var(--on-dark-2);
  padding: clamp(3.5rem, 9vh, 6rem) var(--pad-x);
}

.footer__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  display: grid;
  gap: 1.5rem;
}

.footer__wordmark {
  color: var(--on-dark);
  font-size: 1.5rem;
}

.footer__info p {
  margin: 0.35rem 0;
  font-size: 0.9rem;
  line-height: 1.7;
}

.footer__info a:hover { color: var(--on-dark); text-decoration: underline; }

.footer__sns {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  font-size: 0.85rem;
  letter-spacing: 0.04em;
}

.footer__sns a { color: var(--on-dark-2); transition: color 0.2s ease; }
.footer__sns a:hover { color: var(--on-dark); }

.footer__copy {
  margin-top: 0.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
}

/* ============================================================
   Scroll reveal (.reveal → .is-visible)
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition:
    opacity 0.8s cubic-bezier(0.22, 1, 0.36, 1),
    transform 0.8s cubic-bezier(0.22, 1, 0.36, 1);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* 같은 컨테이너 내 순차 등장(스태거) */
.cards > .reveal:nth-child(2),
.timeline > .reveal:nth-child(2),
.statement__list > .reveal:nth-child(2) { transition-delay: 0.08s; }

.cards > .reveal:nth-child(3),
.timeline > .reveal:nth-child(3),
.statement__list > .reveal:nth-child(3) { transition-delay: 0.16s; }

.timeline > .reveal:nth-child(4) { transition-delay: 0.24s; }

/* ============================================================
   스크롤 진행 표시줄 (상단 얇은 바)
   ============================================================ */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 200;
  height: 2px;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: var(--ink);
  will-change: transform;
}

/* ============================================================
   맨 위로 버튼 (Back to Top)
   ============================================================ */
.to-top {
  position: fixed;
  right: clamp(1rem, 3vw, 2rem);
  bottom: clamp(1rem, 4vh, 2rem);
  z-index: 150;
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: var(--ink);
  color: var(--on-dark);
  font-size: 1.1rem;
  line-height: 1;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s ease, transform 0.3s ease,
    visibility 0.3s ease, background 0.2s ease;
}

.to-top.is-shown {
  opacity: 0.9;
  visibility: visible;
  transform: translateY(0);
}

.to-top:hover { opacity: 1; transform: translateY(-2px); }

/* ============================================================
   페이지 최초 로딩 페이드인 (CSS만 — JS 실패해도 항상 보임)
   ============================================================ */
body {
  animation: page-fade 0.6s ease both;
}

@keyframes page-fade {
  from { opacity: 0; }
  to   { opacity: 1; }
}

/* ============================================================
   prefers-reduced-motion: 모든 모션 끄고 즉시 표시
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  .load-up {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .hero__scroll-arrow { animation: none; }

  .reveal {
    transition: none;
    opacity: 1;
    transform: none;
  }

  .site-header,
  .to-top { transition: none; }

  .product:hover .product__thumb img { transform: none; }
  .product__name { transition: none; }
  .js .product__thumb img { opacity: 1; }

  body { animation: none; }

  .faq__panel,
  .faq__icon::before,
  .faq__icon::after { transition: none; }
}