styles.css

/* ========== AIQ Design Tokens ========== */
:root {
  --color-black: #0a0a0a;
  --color-mint: #3fdd90;
  --color-mint-dark: #45d38e;
  --color-teal: #41c99a;
  --color-white: #ffffff;
  --color-gray: rgba(255, 255, 255, 0.7);
  --color-gray-dim: rgba(255, 255, 255, 0.5);
  --font-display: "Audiowide", sans-serif;
  --font-body: "Pretendard", -apple-system, BlinkMacSystemFont, sans-serif;
  --glow-mint: 0 0 20px rgba(63, 221, 144, 0.4);
  --glow-mint-strong: 0 0 30px rgba(63, 221, 144, 0.6);
}

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

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
  overflow-y: auto;
  max-width: 100vw;
  height: 100%;
}

body {
  margin: 0;
  font-family: var(--font-body);
  background: var(--color-black);
  color: var(--color-white);
  line-height: 1.6;
  overflow-x: hidden;
  overflow-y: auto;
  max-width: 100vw;
  height: 100%;
  -webkit-text-size-adjust: 100%;
  scrollbar-width: thin;
  scrollbar-color: rgba(63, 221, 144, 0.3) transparent;
}

body::-webkit-scrollbar {
  width: 8px;
}

body::-webkit-scrollbar-track {
  background: transparent;
}

body::-webkit-scrollbar-thumb {
  background: rgba(63, 221, 144, 0.3);
  border-radius: 4px;
}

body::-webkit-scrollbar-thumb:hover {
  background: rgba(63, 221, 144, 0.5);
}

/* ========== Shared: Stars background ========== */
.stars {
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(2px 2px at 20px 30px, #fff, transparent),
    radial-gradient(
      2px 2px at 40px 70px,
      rgba(255, 255, 255, 0.8),
      transparent
    ),
    radial-gradient(2px 2px at 50px 160px, #fff, transparent),
    radial-gradient(
      2px 2px at 90px 40px,
      rgba(255, 255, 255, 0.6),
      transparent
    ),
    radial-gradient(2px 2px at 130px 80px, #fff, transparent);
  background-size: 200px 200px;
  animation: twinkle 8s ease-in-out infinite;
  pointer-events: none;
}

@keyframes twinkle {
  0%,
  100% {
    opacity: 1;
  }
  50% {
    opacity: 0.6;
  }
}

/* ========== 1단: 진입 화면 (Hero) - 한 페이지(100vh) 고정 ========== */
.hero {
  position: relative;
  height: 100vh;
  min-height: 100vh;
  max-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem 1.5rem 2.5rem;
  box-sizing: border-box;
  overflow: hidden;
}

/* 배경은 1단 영역(100vh) 안에만 표시 */
.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  height: 100%;
  z-index: 0;
}

/* 배경 이미지(투명 버전): 별(.stars) 위에 겹침 → 별 있는 모습 유지 */
.hero-bg-image {
  position: absolute;
  inset: 0;
  z-index: 1;
  background-image: url("/image/hero-bg.png");
  background-size: cover;
  background-position: center 75%;
  pointer-events: none;
}

/* 배경 행성 - 100vh 기준 하단만 차지, 화면 밖으로 나가지 않음 */
.hero-bg .planet-bottom {
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 180%;
  max-width: 1200px;
  height: 32vh;
  background: radial-gradient(
    ellipse at center,
    #1a2332 0%,
    #0d1520 40%,
    transparent 70%
  );
  border-radius: 50%;
  pointer-events: none;
}

/* 오른쪽 상단 해 이미지 */
/* 해 - 오른쪽 끝선에 맞춤, 크기 축소 */
.hero-bg .sun-corner {
  position: absolute;
  top: 0;
  right: 0;
  width: 30%;
  max-width: 250px;
  height: 30vh;
  margin-right: -10px;
  background-image: url("/image/hero-sun.png");
  background-size: contain;
  background-position: 100% 0;
  background-repeat: no-repeat;
  pointer-events: none;
  z-index: 2;
}

/* 스크롤해도 상단에 고정 */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 2rem;
  padding-top: max(0.75rem, env(safe-area-inset-top));
  padding-left: max(1.5rem, env(safe-area-inset-left));
  padding-right: max(1.5rem, env(safe-area-inset-right));
}

.logo {
  display: flex;
  align-items: center;
  text-decoration: none;
  color: var(--color-white);
  font-family: var(--font-display);
  font-size: 2.5rem;
}

.logo-img {
  height: 2.5rem;
  width: auto;
  display: block;
}

.logo-fallback {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* 로고 이미지가 정상 로드된 경우에만 텍스트 폴백 숨김 */
.logo:has(.logo-img:not([style*="display: none"])) .logo-fallback {
  display: none;
}

.logo-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  background: var(--color-mint);
  color: var(--color-black);
  border-radius: 6px;
  font-weight: bold;
  font-size: 1.5rem;
  box-shadow: var(--glow-mint);
}

.btn-login {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.4rem;
  min-height: 44px;
  line-height: 1.2;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.95);
  background: transparent;
  color: var(--color-white);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  box-shadow: 0 0 12px rgba(255, 255, 255, 0.25);
  transition:
    background 0.2s,
    box-shadow 0.2s;
  margin-right: -0.5rem;
  margin-bottom: 0;
}

.btn-login:hover {
  background: rgba(255, 255, 255, 0.08);
  box-shadow: 0 0 16px rgba(255, 255, 255, 0.35);
}

/* 텍스트 + 캐릭터 + 버튼들 세로 중앙 정렬 - 100vh 안에 수납 */
.hero-main {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  max-width: 520px;
  max-height: 85vh;
  overflow: visible;
  flex-shrink: 0;
  margin-top: 4rem;
}

.hero-content {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  margin-top: 2.5rem;
}

/* 2문장 공간 고정 → 타자 효과 중 캐릭터·버튼 위치 안 움직임 */
.hero-greeting {
  font-family: "Galmuri9", var(--font-body);
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--color-gray);
  margin: 0 0 1.25rem;
  min-height: 3.6rem;
  text-align: center;
  box-sizing: border-box;
}

.typewriter-cursor {
  display: inline-block;
  color: var(--color-mint);
  animation: blink 0.8s step-end infinite;
}

@keyframes blink {
  50% {
    opacity: 0;
  }
}

/* 시작하기 + AIQ 자세히 보기 */
.hero-cta {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  margin-top: 2rem;
}

.hero-mascot {
  position: relative;
  margin: 1.5rem auto 1.25rem;
  width: 380px;
  height: 380px;
}

.mascot-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  animation: mascot-float 3s ease-in-out 0s infinite;
}
.hero.hero-play .mascot-img {
  animation:
    mascot-grow 0.7s ease-out forwards,
    mascot-float 3s ease-in-out 0.7s infinite;
}

/* 거의 안 보일 정도로 작았다가 슈웅 커지는 모션 */
@keyframes mascot-grow {
  0% {
    transform: scale(0.06) translateY(0);
  }
  100% {
    transform: scale(1) translateY(0);
  }
}

/* 그 다음 둥둥 떠있는 모션 */
@keyframes mascot-float {
  0%,
  100% {
    transform: scale(1) translateY(0);
  }
  50% {
    transform: scale(1) translateY(-12px);
  }
}

.btn-start {
  position: relative;
  display: inline-block;
  min-width: 240px;
  min-height: 48px;
  padding: 0.85rem 2.8rem;
  border: 2px solid var(--color-mint);
  border-radius: 999px;
  background: rgba(63, 221, 144, 0.08);
  color: var(--color-white);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  margin-bottom: 0;
  text-align: center;
  box-shadow: var(--glow-mint);
  transition:
    background 0.2s,
    box-shadow 0.2s;
  box-sizing: border-box;
}

.btn-start-text {
  display: inline-block;
}

.btn-start-arrow {
  position: absolute;
  right: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
}

.btn-start:hover {
  background: rgba(63, 221, 144, 0.2);
  box-shadow: var(--glow-mint-strong);
}

/* AIQ 자세히 보기 - 시작하기 버튼 아래, 100vh 안에 보이도록 */
.hero .link-learn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  margin-top: 7.5rem;
  color: var(--color-gray-dim);
  font-size: 0.9rem;
  text-decoration: none;
  transition: color 0.2s;
}

.hero .link-learn:hover {
  color: var(--color-mint);
}

.chevron-down {
  display: block;
  width: 0;
  height: 0;
  border-left: 6px solid transparent;
  border-right: 6px solid transparent;
  border-top: 8px solid currentColor;
}

.chevron-up {
  display: block;
  width: 0;
  height: 0;
  border-left: 6px solid transparent;
  border-right: 6px solid transparent;
  border-bottom: 8px solid currentColor;
}

/* ========== 2단: About AIQ ========== */
.about {
  position: relative;
  padding: 2.5rem 1.5rem 2.5rem;
  min-height: 100vh;
}

.about-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.about-bg-image {
  position: absolute;
  inset: 0;
  z-index: 1;
  background-image: url("/image/about-bg.png");
  background-size: cover;
  background-position: center 20%;
  pointer-events: none;
}

.about-bg .planet-top {
  position: absolute;
  top: -15%;
  left: 50%;
  transform: translateX(-50%);
  width: 120%;
  max-width: 900px;
  height: 40vh;
  background: radial-gradient(ellipse at center, #1a2332 0%, transparent 70%);
  border-radius: 50%;
}

.about-label {
  position: relative;
  z-index: 1;
  text-align: center;
  font-family: "Galmuri9", sans-serif;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-gray);
  margin: 0 0 2rem;
  letter-spacing: 0.1em;
}

.about-title {
  position: relative;
  z-index: 1;
  text-align: center;
  font-family: "Galmuri9", sans-serif;
  font-size: clamp(2.5rem, 6vw, 4rem);
  color: var(--color-mint);
  margin: 0 0 0.5rem;
  text-shadow: var(--glow-mint);
}

.about-tagline {
  position: relative;
  z-index: 1;
  text-align: center;
  font-family: var(--font-body);
  font-size: 1rem;
  color: #45d38e;
  margin: 0 0 2rem;
}

.steps {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
  max-width: 1200px;
  margin: 4rem auto 1.5rem;
}

@media (max-width: 1024px) {
  .steps {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .steps {
    grid-template-columns: 1fr;
  }
}

.step-card {
  padding: 0 1.5rem 1.5rem 1.5rem;
  border: 2px solid var(--color-mint);
  border-radius: 12px;
  background: rgba(0, 0, 0, 0.4);
  box-shadow: var(--glow-mint);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  overflow: visible;
  min-width: 0;
  opacity: 0;
  transform: translateY(14px);
  transition:
    transform 0.25s ease,
    border-color 0.25s ease,
    box-shadow 0.25s ease,
    background 0.25s ease;
  transform-origin: center;
}

/* 2단 진입 시 1→2→3→4 순서대로 빠르게 등장 (애니메이션으로만, 호버는 지연 없음) */
@keyframes step-card-in {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.about.in-view .step-card:nth-child(1) {
  animation: step-card-in 0.32s ease-out forwards;
  animation-delay: 0s;
}
.about.in-view .step-card:nth-child(2) {
  animation: step-card-in 0.32s ease-out forwards;
  animation-delay: 0.1s;
}
.about.in-view .step-card:nth-child(3) {
  animation: step-card-in 0.32s ease-out forwards;
  animation-delay: 0.2s;
}
.about.in-view .step-card:nth-child(4) {
  animation: step-card-in 0.32s ease-out forwards;
  animation-delay: 0.3s;
}

/* 카드 자체는 호버 시 변화 없음, 내부 캐릭터 이미지만 확대 */
.step-card:hover .step-illust img {
  transform: scale(1.08);
  filter: drop-shadow(0 0 16px rgba(63, 221, 144, 0.4))
    drop-shadow(0 0 24px rgba(255, 255, 255, 0.15));
}

.step-num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  background: var(--color-mint);
  color: var(--color-black);
  font-family: var(--font-body);
  font-weight: bold;
  font-size: 1.1rem;
  margin-top: -1.25rem;
  margin-bottom: 1rem;
  box-shadow: var(--glow-mint);
}

.step-title {
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-mint);
  margin: 0 0 0.75rem;
  line-height: 1.3;
}

.step-desc {
  font-family: var(--font-body);
  font-size: 0.85rem;
  color: var(--color-gray);
  margin: 0 0 1rem;
  flex-grow: 1;
}

.step-illust {
  width: 100%;
  min-height: 260px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step-illust img {
  max-width: 100%;
  max-height: 320px;
  width: auto;
  height: auto;
  object-fit: contain;
  transition:
    transform 0.25s ease,
    filter 0.25s ease;
  transform-origin: center center;
}

.step-illust.step-2 img,
.step-illust.step-4 img {
  max-height: 320px;
}

.step-illust.placeholder {
  background: rgba(63, 221, 144, 0.1);
  border-radius: 8px;
  border: 1px dashed var(--color-mint);
}

.link-app-down {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  color: var(--color-gray-dim);
  font-size: 0.9rem;
  text-decoration: none;
  margin: 6rem auto 0;
  width: fit-content;
  transition: color 0.2s;
}

.link-app-down:hover {
  color: var(--color-mint);
}

/* ========== 3단: 앱 소개 + 다운로드 ========== */
.app-section {
  position: relative;
  padding: 0 1.5rem;
  height: 100vh;
  min-height: 100vh;
  max-height: 100vh;
  display: flex;
  align-items: stretch;
  box-sizing: border-box;
  overflow: hidden;
  transition:
    padding 0.35s ease,
    min-height 0.35s ease,
    height 0.35s ease;
}

.app-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.app-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  max-width: 1100px;
  margin: 0 auto;
  align-items: end;
  align-content: end;
  width: 100%;
  padding-bottom: 0;
  padding-top: 20px;
  transition:
    gap 0.35s ease,
    grid-template-columns 0.35s ease;
}

/* 웹앱(반응형) 3단: 휴대폰 → 문구·버튼 → 캐릭터, 아래 공간까지 골고루 활용 */
@media (max-width: 900px) {
  .app-section {
    min-height: 100vh;
    height: 100vh;
    padding: 0.75rem 1rem 0;
    overflow: hidden;
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    transition: padding 0.35s ease;
  }
  .app-section .app-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    gap: 1rem;
    padding-top: 12vh;
    padding-bottom: 0;
    width: 100%;
    max-width: 100%;
    flex: 1 1 auto;
    min-height: 0;
  }
  /* ① 휴대폰: 크기 더 키움, 텍스트와 거리 유지 (gap 1rem) */
  .app-section .app-inner .app-left {
    order: 1;
    width: 100%;
    max-width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    align-self: center;
    margin: 0;
    padding: 0;
    margin-left: 0;
    margin-top: 0;
    flex-shrink: 0;
  }
  .app-section .app-inner .app-left .app-left-img {
    max-height: 360px;
    width: auto;
    max-width: min(400px, 92vw);
    object-fit: contain;
    margin: 0 auto;
    display: block;
  }
  /* ② 문구·버튼 (휴대폰 바로 아래) */
  .app-section .app-inner .app-copy {
    order: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding-bottom: 0;
    min-height: 0;
    width: 100%;
    max-width: 100%;
    flex: 1 1 auto;
    justify-content: flex-start;
  }
  .app-section .app-copy .app-star--top {
    display: none;
  }
  .app-section .app-copy .app-headline {
    text-align: center;
    font-size: 1.05rem;
    margin: 0 0 0.2rem;
    line-height: 1.35;
  }
  .app-section .app-copy .app-headline.app-headline-accent {
    text-align: center;
    font-size: 1.05rem;
  }
  .app-section .app-copy .app-slogan {
    text-align: center;
    font-size: 0.8rem;
    margin: 0 0 0.1rem;
  }
  .app-section .app-copy .app-desc {
    text-align: center;
    font-size: 0.75rem;
    margin: 0 0 0.4rem;
  }
  .app-section .app-copy .app-buttons {
    justify-content: center;
    margin: 0;
    gap: 0.5rem;
  }
  .app-section .app-copy .app-buttons .app-store-link img,
  .app-section .app-copy .app-buttons .google-play-link img {
    height: 42px;
    width: auto;
    object-fit: contain;
  }
  .app-section .app-copy .app-star--mascot {
    margin: 0 auto;
    height: 20px;
  }
  /* ③ 캐릭터: 3단 바닥에 붙이기 + 진입 시 아래에서 위로 올라오는 애니 (웹앱) */
  .app-section .app-copy .app-mascot {
    position: static;
    transform: translateY(80px);
    opacity: 0;
    transition:
      transform 0.9s ease-out,
      opacity 0.7s ease-out;
    justify-content: center;
    align-items: flex-end;
    margin: 0 auto;
    margin-top: auto;
    margin-bottom: 0;
    padding-bottom: 0;
    flex-shrink: 0;
  }
  .app-section .app-copy .app-mascot img {
    max-width: 220px;
    width: auto;
    max-height: 50vh;
    height: auto;
    object-fit: contain;
    object-position: bottom;
    display: block;
    vertical-align: bottom;
  }
  .app-section.in-view .app-copy .app-mascot {
    transform: translateY(0);
    opacity: 1;
  }
}

/* 좌측: 로고·아이콘·폰 통합 이미지 (align-self로 위에 붙임, 왼쪽 이미지만 위·왼쪽으로 이동) */
.app-left {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 0;
  overflow: visible;
  align-self: flex-start;
  margin-left: -6rem;
  margin-top: -3rem;
  transition:
    margin 0.35s ease,
    justify-content 0.35s ease,
    align-self 0.35s ease;
}

.app-left.placeholder {
  min-height: 320px;
  border: 2px dashed var(--color-mint);
  border-radius: 16px;
  background: rgba(63, 221, 144, 0.05);
}

.app-left-img {
  max-width: 100%;
  max-height: 580px;
  width: auto;
  height: auto;
  object-fit: contain;
  filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.4));
}

.app-headline {
  font-family: "Galmuri9", sans-serif;
  font-size: clamp(1.5rem, 3vw, 2rem);
  color: var(--color-white);
  margin: 0 0 0.5rem;
  line-height: 1.3;
  position: relative;
  z-index: 1;
}

/* 3단 진입 시 헤드라인: 깜빡 깜빡 → 보임 */
.app-section .app-copy .app-headline {
  opacity: 0;
}
.app-section.in-view .app-copy .app-headline {
  animation: headline-blink-twice 1.2s ease-out forwards;
}

@keyframes headline-blink-twice {
  0% {
    opacity: 0;
  }
  20% {
    opacity: 1;
  }
  40% {
    opacity: 0;
  }
  60% {
    opacity: 1;
  }
  80% {
    opacity: 0;
  }
  100% {
    opacity: 1;
  }
}

.app-headline-accent {
  color: #41c99a;
  white-space: nowrap;
}

.app-slogan {
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-gray);
  margin: 0 0 0.25rem;
  position: relative;
  z-index: 1;
}

.app-desc {
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--color-gray);
  margin: 0 0 1rem;
  position: relative;
  z-index: 1;
}

.app-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 0.75rem;
  justify-content: flex-end;
  position: relative;
  z-index: 1;
}

.app-store-link,
.google-play-link {
  display: inline-block;
  text-decoration: none;
  transition: opacity 0.2s;
}

.app-store-link:hover,
.google-play-link:hover {
  opacity: 0.9;
}

.app-store-link img,
.google-play-link img {
  display: block;
  height: 72px;
  width: auto;
  object-fit: contain;
}

.app-copy {
  display: flex;
  flex-direction: column;
  position: relative;
  padding-bottom: 320px;
  text-align: right;
  align-items: flex-end;
}

/* 3단 장식 별 (같은 이미지 app-star.png, 방향만 조정) */
.app-star {
  position: absolute;
  width: auto;
  height: 48px;
  max-height: 6vw;
  object-fit: contain;
  pointer-events: none;
  z-index: 1;
}

.app-star--top {
  top: -4.5rem;
  right: 0;
  transform: scale(1);
}

.app-star--mascot {
  bottom: 120px;
  left: 3rem;
  transform: scaleX(-1);
}

.app-mascot {
  position: absolute;
  bottom: 0;
  right: 0;
  margin: 0;
  width: auto;
  max-width: 100%;
  display: flex;
  justify-content: flex-end;
  align-items: flex-end;
  padding: 0;
  line-height: 0;
  pointer-events: none;
  z-index: 1;
  transform: translateY(80px);
  opacity: 0;
  transition:
    transform 0.9s ease-out,
    opacity 0.7s ease-out;
}

.app-section.in-view .app-mascot {
  transform: translateY(0);
  opacity: 1;
}

.app-mascot img {
  max-width: 360px;
  width: auto;
  height: auto;
  max-height: 55vh;
  object-fit: contain;
  object-position: bottom;
  vertical-align: bottom;
  display: block;
  margin-bottom: 0;
}

/* 3단 하단: 푸터로 내리는 버튼 (단순 회색 세모) */
.btn-to-footer {
  position: absolute;
  bottom: 1rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2;
  width: 1.5rem;
  height: 1.5rem;
  border: none;
  border-radius: 0;
  background: transparent;
  color: rgba(255, 255, 255, 0.5);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  transition: color 0.2s;
}

.btn-to-footer:hover {
  color: rgba(255, 255, 255, 0.75);
}

.btn-to-footer:focus {
  outline: none;
  color: rgba(255, 255, 255, 0.75);
}

.btn-to-footer .chevron-down {
  color: currentColor;
}

/* ========== 4단: 푸터 ========== */
.footer {
  background: var(--color-black);
  padding: 3rem 2rem 2rem;
  border-top: 1px solid rgba(63, 221, 144, 0.2);
}

.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 3rem;
}

@media (max-width: 700px) {
  .footer-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }
  .footer-nav {
    flex-direction: column;
    align-items: center;
  }
}

/* 웹앱: 4단 푸터 — 네비(서비스·정책) 가로 배치 + 상단에 배치 */
@media (max-width: 900px) {
  .footer-inner {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    text-align: center;
  }
  .footer-left {
    order: -1;
  }
  .footer .copyright {
    margin-top: 3rem;
    margin-bottom: 0;
  }
  .footer-nav {
    order: 1;
    margin-top: 2.5rem;
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
    align-items: flex-start;
    gap: 2rem 3rem;
  }
  .footer .nav-col {
    text-align: center;
  }
  .footer .nav-col h4 {
    margin-bottom: 0.5rem;
  }
  .footer .nav-col ul {
    margin: 0;
    padding: 0;
    list-style: none;
  }
  .footer .nav-col li {
    margin-bottom: 0.5rem;
  }
  .footer .nav-col li:last-child {
    margin-bottom: 0;
  }
}

.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
  color: var(--color-mint);
  font-family: var(--font-display);
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.footer-logo-img {
  height: 2.5rem;
  width: auto;
}

.footer-logo .logo-icon {
  background: var(--color-mint);
  color: var(--color-black);
}

.footer-tagline {
  font-size: 0.9rem;
  color: var(--color-gray);
  margin: 0 0 1.5rem;
}

.footer-contact p {
  margin: 0 0 0.35rem;
  font-size: 0.9rem;
  color: var(--color-gray);
}

.footer-contact a {
  color: var(--color-mint);
  text-decoration: none;
}

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

.contact-note {
  font-size: 0.8rem !important;
  color: var(--color-gray-dim) !important;
}

.copyright {
  margin-top: 2rem;
  font-size: 0.85rem;
  color: var(--color-gray-dim);
}

/* ========== 맨 위로 버튼 (2단부터 표시, 얇은 원 테두리 + 위쪽 세모, 초록) ========== */
.btn-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 999;
  width: 2.25rem;
  height: 2.25rem;
  border: 1.5px solid var(--color-mint);
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.7);
  color: var(--color-mint);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(0.5rem);
  transition:
    opacity 0.25s,
    visibility 0.25s,
    transform 0.25s,
    border-color 0.2s,
    color 0.2s;
  pointer-events: none;
  backdrop-filter: blur(4px);
}

.btn-top.is-visible {
  pointer-events: auto;
}

.btn-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.btn-top:hover,
.btn-top:focus {
  color: #5ae8a8;
  border-color: #5ae8a8;
}

.btn-top:focus {
  outline: none;
}

.btn-top-chevron {
  color: currentColor;
}

.footer-nav {
  display: flex;
  gap: 3rem;
}

.nav-col h4 {
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-white);
  margin: 0 0 0.75rem;
}

.nav-col ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-col li {
  margin-bottom: 0.5rem;
}

.nav-col a {
  color: var(--color-gray);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s;
}

.nav-col a:hover {
  color: var(--color-mint);
}

/* ========== 반응형: 태블릿 (900px 이하) ========== */
@media (max-width: 900px) {
  .header {
    padding: 1rem 1.25rem;
  }
  .logo {
    font-size: 2rem;
  }
  .logo-img {
    height: 2.75rem;
  }
  .logo-icon {
    width: 2.5rem;
    height: 2.5rem;
    font-size: 1.25rem;
  }
  .btn-login {
    padding: 0.5rem 0.85rem;
    min-height: 36px;
    font-size: 0.85rem;
    line-height: 1.2;
  }
  .hero-main {
    margin-top: 3rem;
    max-width: 100%;
    padding: 0 0.5rem;
  }
  .hero-content {
    margin-top: 1.5rem;
  }
  .hero-greeting {
    font-size: 0.95rem;
    min-height: 3.2rem;
  }
  .hero-mascot {
    width: 280px;
    height: 280px;
    margin-bottom: 1rem;
  }
  .hero-cta {
    margin-top: -1.5rem;
  }
  .btn-start {
    min-width: 200px;
    padding: 0.75rem 2rem;
    font-size: 0.9rem;
  }
  .btn-start-arrow {
    right: 1rem;
  }
  .hero .link-learn {
    margin-top: 5rem;
    font-size: 0.85rem;
  }
  .about {
    padding: 2rem 1.25rem 2rem;
  }
  .about-title {
    font-size: clamp(2rem, 5vw, 3rem);
  }
  .about-tagline {
    font-size: 0.95rem;
  }
  .steps {
    gap: 1.5rem;
    margin: 3rem auto 1.25rem;
    padding: 0 0.5rem;
  }
  .step-card {
    padding: 0 1.25rem 1.25rem;
  }
  .step-title {
    font-size: 0.95rem;
  }
  .step-desc {
    font-size: 0.8rem;
  }
  .step-illust {
    min-height: 180px;
  }
  .step-illust img {
    max-height: 220px;
  }
  .step-illust.step-2 img,
  .step-illust.step-4 img {
    max-height: 220px;
  }
  .link-app-down {
    margin: 1.5rem auto 0;
    font-size: 0.85rem;
  }
  /* 3단 모바일 레이아웃·크기는 위 900px 3단 전용 블록에서만 적용 */
  .footer {
    padding: 2rem 1.25rem;
  }
  .footer-inner {
    gap: 2rem;
  }
}

/* ========== 반응형: 모바일 (600px 이하) ========== */
@media (max-width: 600px) {
  .header {
    padding: 0.75rem 1rem;
  }
  .logo {
    font-size: 1.75rem;
  }
  .logo-img {
    height: 2.25rem;
  }
  .logo-icon {
    width: 2rem;
    height: 2rem;
    font-size: 1rem;
  }
  .btn-login {
    padding: 0.4rem 0.7rem;
    min-height: 32px;
    font-size: 0.8rem;
    line-height: 1.2;
  }
  .hero {
    padding: 1.5rem 1rem 2rem;
  }
  .hero-main {
    margin-top: 2.5rem;
  }
  .hero-content {
    margin-top: 1rem;
  }
  .hero-greeting {
    font-size: 0.875rem;
    line-height: 1.6;
    min-height: 2.8rem;
  }
  .hero-mascot {
    width: 220px;
    height: 220px;
    margin-bottom: 0.75rem;
  }
  .hero-cta {
    margin-top: -1rem;
  }
  .btn-start {
    min-width: 100%;
    max-width: 280px;
    padding: 0.7rem 1.5rem;
    font-size: 0.875rem;
  }
  .btn-start-arrow {
    right: 1rem;
  }
  .hero .link-learn {
    margin-top: 3.5rem;
    font-size: 0.8rem;
  }
  .hero-bg .sun-corner {
    width: 40%;
    max-width: 140px;
    height: 22vh;
  }
  .about {
    padding: 1.5rem 1rem 1.5rem;
  }
  .about-label {
    font-size: 0.8rem;
  }
  .about-title {
    font-size: clamp(1.75rem, 8vw, 2.5rem);
  }
  .about-tagline {
    font-size: 0.875rem;
    margin: 0 0 1rem;
  }
  .steps {
    margin: 2rem auto 1rem;
    gap: 2rem;
    padding: 0 1rem;
    max-width: 360px;
    width: 100%;
    box-sizing: border-box;
  }
  .step-card {
    padding: 0 1rem 1rem;
  }
  .step-num {
    width: 2.25rem;
    height: 2.25rem;
    font-size: 1rem;
    margin-top: -1.125rem;
    margin-bottom: 0.75rem;
  }
  .step-title {
    font-size: 0.9rem;
    margin: 0 0 0.5rem;
  }
  .step-desc {
    font-size: 0.75rem;
    margin: 0 0 0.75rem;
  }
  .step-illust {
    min-height: 120px;
  }
  .step-illust img {
    max-height: 160px;
  }
  .step-illust.step-2 img,
  .step-illust.step-4 img {
    max-height: 160px;
  }
  .step-illust.step-4 img {
    max-height: 120px;
  }
  .link-app-down {
    margin: 1.25rem auto 0;
    font-size: 0.8rem;
  }
  /* 3단: 600px 크기 조정 (휴대폰→문구·버튼→캐릭터 유지) */
  .app-section {
    padding: 0.875rem 0.75rem 1.25rem;
  }
  .app-inner {
    gap: 0.45rem;
    padding-bottom: 0.5rem;
  }
  .app-section .app-inner .app-left .app-left-img {
    max-height: 300px;
    max-width: 360px;
  }
  .app-left.placeholder {
    min-height: 120px;
  }
  .app-copy .app-headline,
  .app-copy .app-headline.app-headline-accent {
    font-size: 0.98rem;
  }
  .app-copy .app-slogan {
    font-size: 0.72rem;
  }
  .app-copy .app-desc {
    font-size: 0.68rem;
  }
  .app-section .app-copy .app-buttons .app-store-link img,
  .app-section .app-copy .app-buttons .google-play-link img {
    height: 38px;
  }
  .app-section .app-copy .app-mascot img {
    max-width: 180px;
    max-height: 42vh;
  }
  .footer {
    padding: 1.5rem 1rem;
  }
  .footer-inner {
    gap: 1.5rem;
  }
  .footer-logo {
    font-size: 1.25rem;
  }
  .footer-tagline,
  .footer-contact p {
    font-size: 0.85rem;
  }
  .footer-nav {
    gap: 2rem;
  }
  .nav-col h4 {
    font-size: 0.85rem;
  }
  .nav-col a {
    font-size: 0.85rem;
  }
  .copyright {
    margin-top: 1.5rem;
    font-size: 0.8rem;
  }
}

/* ========== 서비스 소개 팝업 모달 ========== */
.service-intro-overlay {
  position: fixed;
  inset: 0;
  background: rgba(10, 10, 10, 0.85);
  backdrop-filter: blur(4px);
  z-index: 1000;
  animation: fadeIn 0.2s ease-out;
}

.service-intro-modal {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 90%;
  max-width: 800px;
  max-height: 90vh;
  background: var(--color-black);
  border: 1px solid rgba(63, 221, 144, 0.3);
  border-radius: 12px;
  box-shadow:
    0 8px 32px rgba(0, 0, 0, 0.5),
    var(--glow-mint);
  z-index: 1001;
  display: flex;
  flex-direction: column;
  animation: slideUp 0.3s ease-out;
  overflow: hidden;
}

.service-intro-close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(63, 221, 144, 0.1);
  border: 1px solid rgba(63, 221, 144, 0.3);
  border-radius: 8px;
  color: var(--color-mint);
  cursor: pointer;
  transition: all 0.2s;
  z-index: 10;
}

.service-intro-close:hover {
  background: rgba(63, 221, 144, 0.2);
  border-color: var(--color-mint);
  box-shadow: var(--glow-mint);
}

.service-intro-close:active {
  transform: scale(0.95);
}

.service-intro-content {
  padding: 2.5rem 2rem 2rem;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: rgba(63, 221, 144, 0.3) transparent;
}

.service-intro-content::-webkit-scrollbar {
  width: 8px;
}

.service-intro-content::-webkit-scrollbar-track {
  background: transparent;
}

.service-intro-content::-webkit-scrollbar-thumb {
  background: rgba(63, 221, 144, 0.3);
  border-radius: 4px;
}

.service-intro-content::-webkit-scrollbar-thumb:hover {
  background: rgba(63, 221, 144, 0.5);
}

.service-intro-title {
  font-family: var(--font-display);
  font-size: 2rem;
  color: var(--color-mint);
  margin: 0 0 2rem;
  line-height: 1.3;
  text-align: center;
}

.service-intro-section {
  margin-bottom: 2rem;
}

.service-intro-section:last-child {
  margin-bottom: 0;
}

.service-intro-quote {
  font-size: 1.2rem;
  color: var(--color-mint);
  font-weight: 600;
  margin: 0 0 1.5rem;
  text-align: center;
  font-style: italic;
}

.service-intro-subtitle {
  font-size: 1.3rem;
  color: var(--color-white);
  margin: 0 0 1rem;
  font-weight: 600;
  border-bottom: 1px solid rgba(63, 221, 144, 0.2);
  padding-bottom: 0.5rem;
}

.service-intro-text {
  font-size: 1rem;
  color: var(--color-gray);
  line-height: 1.8;
  margin: 0 0 1rem;
}

.service-intro-text:last-child {
  margin-bottom: 0;
}

.service-intro-list {
  list-style: none;
  padding: 0;
  margin: 0 0 1rem;
}

.service-intro-list li {
  font-size: 1rem;
  color: var(--color-gray);
  line-height: 1.8;
  margin-bottom: 1rem;
  padding-left: 1.5rem;
  position: relative;
}

.service-intro-list li:last-child {
  margin-bottom: 0;
}

.service-intro-list li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--color-mint);
  font-weight: bold;
  font-size: 1.2rem;
}

.service-intro-list--numbered {
  counter-reset: item;
}

.service-intro-list--numbered li {
  counter-increment: item;
  padding-left: 2rem;
}

.service-intro-list--numbered li::before {
  content: counter(item) ".";
  position: absolute;
  left: 0;
  color: var(--color-mint);
  font-weight: bold;
  font-size: 1rem;
}

.service-intro-list strong {
  color: var(--color-white);
  font-weight: 600;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translate(-50%, -40%);
  }
  to {
    opacity: 1;
    transform: translate(-50%, -50%);
  }
}

/* 개인정보 동의 버튼 */
.privacy-agree-wrap {
  padding: 1.5rem 2rem 2rem;
  text-align: center;
  border-top: 1px solid rgba(63, 221, 144, 0.15);
}

.privacy-agree-btn {
  width: 100%;
  padding: 0.875rem 2rem;
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.06);
  color: rgba(255, 255, 255, 0.3);
  font-size: 1rem;
  font-weight: 600;
  cursor: not-allowed;
  transition: all 0.3s ease;
}

.privacy-agree-btn--active {
  background: var(--color-mint);
  color: #0a0a0a;
  border-color: var(--color-mint);
  cursor: pointer;
  box-shadow: var(--glow-mint);
}

.privacy-agree-btn--active:hover {
  filter: brightness(1.1);
  transform: translateY(-1px);
}

.privacy-agree-hint {
  margin-top: 0.5rem;
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.4);
}

/* 반응형: 태블릿 */
@media (max-width: 900px) {
  .service-intro-modal {
    width: 92%;
    max-width: 700px;
    max-height: 92vh;
  }

  .service-intro-content {
    padding: 2rem 1.75rem 1.75rem;
  }

  .service-intro-title {
    font-size: 1.75rem;
    margin-bottom: 1.75rem;
  }

  .service-intro-subtitle {
    font-size: 1.2rem;
  }

  .service-intro-text {
    font-size: 0.95rem;
  }
}

/* 반응형: 모바일 */
@media (max-width: 600px) {
  .service-intro-modal {
    width: 95%;
    max-height: 92vh;
    border-radius: 8px;
  }

  .service-intro-content {
    padding: 1.5rem 1.25rem 1.25rem;
  }

  .service-intro-close {
    top: 0.75rem;
    right: 0.75rem;
    width: 32px;
    height: 32px;
  }

  .service-intro-title {
    font-size: 1.3rem;
    margin-bottom: 1.25rem;
  }

  .service-intro-quote {
    font-size: 0.9rem;
    margin-bottom: 0.875rem;
  }

  .service-intro-subtitle {
    font-size: 1rem;
    margin-bottom: 0.625rem;
  }

  .service-intro-text {
    font-size: 0.85rem;
    line-height: 1.6;
    margin-bottom: 0.75rem;
  }

  .service-intro-list li {
    font-size: 0.85rem;
    padding-left: 1.125rem;
    margin-bottom: 0.75rem;
    line-height: 1.6;
  }

  .service-intro-list--numbered li {
    padding-left: 1.5rem;
  }

  .service-intro-section {
    margin-bottom: 1.25rem;
  }
}

/* 반응형: 소형 모바일 */
@media (max-width: 400px) {
  .service-intro-modal {
    width: 96%;
    max-height: 90vh;
    border-radius: 6px;
  }

  .service-intro-content {
    padding: 1.25rem 1rem 1rem;
  }

  .service-intro-close {
    top: 0.625rem;
    right: 0.625rem;
    width: 28px;
    height: 28px;
  }

  .service-intro-title {
    font-size: 1.15rem;
    margin-bottom: 1rem;
  }

  .service-intro-quote {
    font-size: 0.85rem;
    margin-bottom: 0.75rem;
  }

  .service-intro-subtitle {
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
  }

  .service-intro-text {
    font-size: 0.8rem;
    line-height: 1.5;
    margin-bottom: 0.625rem;
  }

  .service-intro-list li {
    font-size: 0.8rem;
    padding-left: 1rem;
    margin-bottom: 0.625rem;
    line-height: 1.5;
  }

  .service-intro-list--numbered li {
    padding-left: 1.25rem;
  }

  .service-intro-section {
    margin-bottom: 1rem;
  }
}

/* ========== 반응형: 소형 모바일 (400px 이하) ========== */
@media (max-width: 400px) {
  .hero-mascot {
    width: 180px;
    height: 180px;
  }
  .hero-greeting {
    font-size: 0.8rem;
    min-height: 2.6rem;
  }
  .about-title {
    font-size: 1.5rem;
  }
  .steps {
    max-width: 340px;
    gap: 1.75rem;
  }
  .step-illust {
    min-height: 100px;
  }
  .step-illust img {
    max-height: 140px;
  }
  .step-illust.step-2 img,
  .step-illust.step-4 img {
    max-height: 140px;
  }
  .step-illust.step-4 img {
    max-height: 100px;
  }
  /* 3단: 400px 크기 조정 */
  .app-section .app-inner .app-left .app-left-img {
    max-height: 260px;
    max-width: 320px;
  }
  .app-copy .app-headline,
  .app-copy .app-headline.app-headline-accent {
    font-size: 0.9rem;
  }
  .app-copy .app-slogan {
    font-size: 0.68rem;
  }
  .app-copy .app-desc {
    font-size: 0.65rem;
  }
  .app-section .app-copy .app-buttons .app-store-link img,
  .app-section .app-copy .app-buttons .google-play-link img {
    height: 34px;
  }
  .app-section .app-copy .app-mascot img {
    max-width: 150px;
    max-height: 36vh;
  }
}

/* ========== 마우스 따라다니는 별빛 파티클 효과 ========== */
.mouse-sparkle {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  width: 100vw;
  height: 100vh;
  transition: opacity 0.5s ease;
}