/* ============================================
   0. 테마 변수 - 색상/폰트를 여기서 한번에 관리
   ============================================ */
:root {
  --bg: #0b0f19;
  --bg-soft: #111827;
  --text: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --line: rgba(255, 255, 255, 0.09);
  --glass: rgba(255, 255, 255, 0.06);

  --accent: #38bdf8;      /* 메인 브랜드 컬러 (하늘색) */
  --accent-2: #a78bfa;    /* 보조 컬러 (보라) */
  --accent-3: #f472b6;    /* 포인트 컬러 (핑크) */

  --radius-lg: 28px;
  --radius-md: 20px;
  --radius-sm: 12px;
  --container-w: min(1120px, 92%);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Pretendard", "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
}

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

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

.container {
  width: var(--container-w);
  margin: 0 auto;
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

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

/* ============================================
   1. 헤더
   ============================================ */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  backdrop-filter: blur(18px);
  background: rgba(11, 15, 25, 0.72);
  border-bottom: 1px solid var(--line);
}

.nav {
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.5px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-mark {
  width: 30px;
  height: 30px;
  border-radius: 9px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  display: grid;
  place-items: center;
  font-size: 15px;
}

.nav-menu {
  display: flex;
  gap: 28px;
  font-size: 15px;
  color: #cbd5e1;
}

.nav-menu a {
  position: relative;
  padding: 4px 0;
}

.nav-menu a:hover {
  color: #ffffff;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 14px;
}

.nav-btn {
  padding: 10px 18px;
  border-radius: 999px;
  background: #ffffff;
  color: var(--bg);
  font-weight: 700;
  font-size: 14px;
  white-space: nowrap;
}

/* 모바일 햄버거 버튼 (기본은 숨김) */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 26px;
  cursor: pointer;
  background: none;
  border: none;
}

.hamburger span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--text);
  border-radius: 2px;
  transition: 0.25s;
}

/* 모바일 드롭다운 메뉴 */
.mobile-menu {
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: 12px var(--container-w) 20px;
  background: rgba(11, 15, 25, 0.98);
  border-bottom: 1px solid var(--line);
}

.mobile-menu.is-open {
  display: flex;
}

.mobile-menu a {
  padding: 12px 6px;
  color: #cbd5e1;
  font-size: 15px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

/* ============================================
   2. 히어로 섹션
   ============================================ */
.hero {
  min-height: 100vh;
  padding-top: 150px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  width: 620px;
  height: 620px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.35), transparent 65%);
  top: -180px;
  right: -160px;
  z-index: -1;
}

.hero::after {
  content: "";
  position: absolute;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(168, 85, 247, 0.28), transparent 65%);
  bottom: -160px;
  left: -160px;
  z-index: -1;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 60px;
  align-items: center;
  padding-bottom: 80px;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  margin-bottom: 22px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 999px;
  color: #bae6fd;
  background: var(--glass);
  font-size: 14px;
}

.badge .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #4ade80;
  box-shadow: 0 0 8px #4ade80;
}

.hero h1 {
  font-size: clamp(40px, 6vw, 72px);
  line-height: 1.15;
  letter-spacing: -2.5px;
  margin-bottom: 24px;
}

.hero h1 span {
  background: linear-gradient(135deg, var(--accent), var(--accent-2), var(--accent-3));
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  font-size: 18.5px;
  color: #cbd5e1;
  max-width: 560px;
  margin-bottom: 34px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.btn-primary,
.btn-secondary {
  padding: 15px 22px;
  border-radius: 14px;
  font-weight: 800;
  font-size: 15px;
  transition: 0.25s;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  border: none;
  cursor: pointer;
  font-family: inherit;
}

.btn-primary {
  background: var(--accent);
  color: #06121f;
  box-shadow: 0 18px 50px rgba(56, 189, 248, 0.25);
}

.btn-primary:hover {
  transform: translateY(-3px);
  background: #7dd3fc;
}

.btn-secondary {
  border: 1px solid rgba(255, 255, 255, 0.14);
  color: #e2e8f0;
  background: var(--glass);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
}

.hero-stats {
  display: flex;
  gap: 34px;
  flex-wrap: wrap;
}

.hero-stats div strong {
  display: block;
  font-size: 26px;
  letter-spacing: -1px;
}

.hero-stats div span {
  font-size: 13.5px;
  color: var(--text-muted);
}

/* 폰 목업 카드 (히어로용) */
.phone-card {
  position: relative;
  padding: 18px;
  border-radius: 36px;
  background: linear-gradient(145deg, rgba(255,255,255,0.14), rgba(255,255,255,0.04));
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 30px 100px rgba(0, 0, 0, 0.4);
}

.mockup {
  border-radius: 28px;
  overflow: hidden;
  background: var(--bg-soft);
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.mockup-top {
  padding: 18px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.mockup-top strong {
  font-size: 18px;
}

.chip {
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(34, 197, 94, 0.14);
  color: #86efac;
  font-size: 12px;
  font-weight: 700;
}

.photo-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  padding: 0 18px 18px;
}

.photo {
  height: 100px;
  border-radius: 18px;
  background-size: cover;
  background-position: center;
}

/* 사진 목업용 그라데이션 - 실제 이미지로 교체 가능 */
.photo.c1 { background: linear-gradient(135deg, #38bdf8, #0f172a); }
.photo.c2 { background: linear-gradient(135deg, #fb7185, #312e81); }
.photo.c3 { background: linear-gradient(135deg, #facc15, #ea580c); }
.photo.c4 { background: linear-gradient(135deg, #22c55e, #064e3b); }
.photo.c5 { background: linear-gradient(135deg, #a78bfa, #1e1b4b); }
.photo.c6 { background: linear-gradient(135deg, #f97316, #7c2d12); }

.route-card {
  margin: 0 18px 18px;
  padding: 18px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.route-card h3 {
  font-size: 16px;
  margin-bottom: 12px;
}

.timeline {
  display: flex;
  flex-direction: column;
  gap: 10px;
  color: #cbd5e1;
  font-size: 13.5px;
}

.timeline div::before {
  content: "●";
  color: var(--accent);
  margin-right: 8px;
}

/* ============================================
   공통 섹션 스타일
   ============================================ */
section {
  padding: 110px 0;
}

.section-title {
  text-align: center;
  margin-bottom: 56px;
}

.section-title span.eyebrow {
  color: var(--accent);
  font-weight: 800;
  font-size: 13px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
}

.section-title h2 {
  font-size: clamp(30px, 4vw, 48px);
  letter-spacing: -1.6px;
  margin-top: 10px;
}

.section-title p {
  margin-top: 16px;
  color: var(--text-muted);
  font-size: 17.5px;
  max-width: 560px;
  margin-inline: auto;
}

/* ============================================
   3. 핵심 기능 소개
   ============================================ */
.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.feature-card {
  padding: 30px;
  border-radius: 26px;
  background: rgba(255, 255, 255, 0.055);
  border: 1px solid var(--line);
  transition: 0.25s;
}

.feature-card:hover {
  transform: translateY(-6px);
  background: rgba(255, 255, 255, 0.085);
}

.icon {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  border-radius: 15px;
  background: rgba(56, 189, 248, 0.14);
  color: #7dd3fc;
  font-size: 23px;
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 20px;
  margin-bottom: 12px;
  letter-spacing: -0.3px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 15px;
}

/* ============================================
   4. 작동 방식
   ============================================ */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.step {
  padding: 26px;
  border-radius: 24px;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  position: relative;
}

.step-number {
  color: var(--accent);
  font-size: 13px;
  font-weight: 900;
  margin-bottom: 16px;
  letter-spacing: 1px;
}

.step h3 {
  font-size: 18.5px;
  margin-bottom: 10px;
}

.step p {
  color: var(--text-muted);
  font-size: 14.5px;
}

/* ============================================
   5. 앱 미리보기 UI (탭 인터랙션)
   ============================================ */
.preview-wrap {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 50px;
  align-items: center;
}

.tab-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.tab-btn {
  text-align: left;
  padding: 16px 20px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--line);
  color: var(--text-muted);
  font-family: inherit;
  cursor: pointer;
  transition: 0.2s;
}

.tab-btn strong {
  display: block;
  color: var(--text);
  font-size: 16px;
  margin-bottom: 4px;
}

.tab-btn span {
  font-size: 13.5px;
}

.tab-btn:hover {
  background: rgba(255, 255, 255, 0.07);
}

/* 현재 선택된 탭 스타일 - JS가 is-active 클래스를 토글 */
.tab-btn.is-active {
  background: rgba(56, 189, 248, 0.12);
  border-color: rgba(56, 189, 248, 0.4);
}

.tab-btn.is-active strong {
  color: #7dd3fc;
}

.preview-screen {
  border-radius: 32px;
  padding: 26px;
  background: linear-gradient(160deg, rgba(255,255,255,0.09), rgba(255,255,255,0.02));
  border: 1px solid var(--line);
  min-height: 380px;
}

.preview-panel {
  display: none;
}

.preview-panel.is-active {
  display: block;
  animation: fadeIn 0.4s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.preview-panel h4 {
  font-size: 19px;
  margin-bottom: 18px;
}

.preview-photo-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.preview-photo-grid .photo {
  height: 78px;
  border-radius: 14px;
}

/* ============================================
   6. 베타 신청 CTA
   ============================================ */
.cta {
  padding: 70px 40px;
  border-radius: 36px;
  text-align: center;
  background:
    linear-gradient(135deg, rgba(56, 189, 248, 0.18), rgba(168, 85, 247, 0.16)),
    rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.cta h2 {
  font-size: clamp(30px, 5vw, 52px);
  letter-spacing: -1.8px;
  margin-bottom: 16px;
}

.cta p {
  color: #cbd5e1;
  font-size: 17px;
  margin-bottom: 30px;
  max-width: 480px;
  margin-inline: auto;
}

/* 베타 신청 폼 - 백엔드 없이 JS로만 동작 */
.signup-form {
  display: flex;
  gap: 10px;
  max-width: 440px;
  margin: 0 auto;
  flex-wrap: wrap;
  justify-content: center;
}

.signup-form input[type="email"] {
  flex: 1;
  min-width: 220px;
  padding: 15px 18px;
  border-radius: 14px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(11, 15, 25, 0.5);
  color: var(--text);
  font-size: 15px;
  font-family: inherit;
}

.signup-form input[type="email"]::placeholder {
  color: var(--text-dim);
}

.signup-form input[type="email"]:focus {
  outline: none;
  border-color: var(--accent);
}

.form-message {
  margin-top: 14px;
  font-size: 14px;
  min-height: 20px;
}

.form-message.success {
  color: #86efac;
}

.form-message.error {
  color: #fca5a5;
}

/* ============================================
   7. 푸터
   ============================================ */
footer {
  padding: 44px 0 34px;
  border-top: 1px solid var(--line);
}

.footer-grid {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 24px;
  margin-bottom: 28px;
}

.footer-brand p {
  color: var(--text-dim);
  font-size: 14px;
  margin-top: 8px;
  max-width: 320px;
}

.footer-links {
  display: flex;
  gap: 40px;
  flex-wrap: wrap;
}

.footer-col h4 {
  font-size: 14px;
  margin-bottom: 12px;
  color: var(--text-muted);
}

.footer-col a {
  display: block;
  color: var(--text-dim);
  font-size: 14px;
  padding: 5px 0;
}

.footer-col a:hover {
  color: var(--text);
}

.footer-bottom {
  color: var(--text-dim);
  font-size: 13.5px;
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

/* ============================================
   반응형 (태블릿 / 모바일)
   ============================================ */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .features {
    grid-template-columns: 1fr 1fr;
  }

  .steps {
    grid-template-columns: 1fr 1fr;
  }

  .preview-wrap {
    grid-template-columns: 1fr;
  }

  .nav-menu {
    display: none;
  }

  .hamburger {
    display: flex;
  }
}

@media (max-width: 560px) {
  .hero {
    padding-top: 120px;
  }

  .hero h1 {
    letter-spacing: -1.5px;
  }

  .features {
    grid-template-columns: 1fr;
  }

  .steps {
    grid-template-columns: 1fr;
  }

  .photo {
    height: 84px;
  }

  .preview-photo-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .nav-btn {
    display: none;
  }

  .signup-form {
    flex-direction: column;
  }

  .footer-grid {
    flex-direction: column;
  }
}