/* ── Habits marketing site palette ───────────────────────────────────────────
   iOS アプリの dark theme を反映。primary は App アイコンのコバルト #3b82e6。
   bgApp #1f212a  surface #272f3d  surface2 #323b4a  line #3e485a
   ink #f5f7f9  ink2 #c1c4c8  ink3 #82878c  ink4 #565b63
   primary #3b82e6  primary-bright #6ea8f8
   accents: sky #48bff5  sage #69d49a  amber #f6b84d  coral #ff7e70
*/

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

body {
  font-family: "Inter", "Noto Sans JP", -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.7;
  color: #f5f7f9;
  background-color: #1f212a;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.header {
  background-color: rgba(31, 33, 42, 0.82);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.05);
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
}

.nav-logo-mark {
  width: 28px;
  height: 28px;
  border-radius: 7px;
  display: block;
}

.nav-logo h1 {
  color: #f5f7f9;
  font-family: "Inter", "Noto Sans JP", sans-serif;
  font-size: 1.4rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 1.8rem;
}

.nav-menu a {
  text-decoration: none;
  color: #c1c4c8;
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.3s ease;
}

.nav-menu a:hover {
  color: #6ea8f8;
}

.language-switcher {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
}

.lang-btn {
  background: transparent;
  border: none;
  color: #c1c4c8;
  cursor: pointer;
  font: inherit;
  padding: 4px 10px;
  border-radius: 999px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.lang-btn:hover {
  background-color: rgba(110, 168, 248, 0.14);
  color: #6ea8f8;
}

.lang-btn.active {
  background-color: #3b82e6;
  color: #fff;
}

.lang-separator {
  color: #565b63;
  font-size: 0.8rem;
}

/* Hero Section */
.hero {
  background:
    radial-gradient(circle at 20% 20%, rgba(59, 130, 230, 0.22) 0%, transparent 60%),
    radial-gradient(circle at 80% 80%, rgba(72, 191, 245, 0.14) 0%, transparent 60%),
    linear-gradient(135deg, #1f212a 0%, #232a3a 100%);
  color: #f5f7f9;
  padding: 120px 0 80px;
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -40%;
  right: -10%;
  width: 520px;
  height: 520px;
  background: radial-gradient(circle, rgba(59, 130, 230, 0.28) 0%, transparent 70%);
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: -20%;
  left: -5%;
  width: 380px;
  height: 380px;
  background: radial-gradient(circle, rgba(72, 191, 245, 0.16) 0%, transparent 70%);
  pointer-events: none;
}

.hero-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-title {
  font-family: "Inter", "Noto Sans JP", sans-serif;
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 1.5rem;
  line-height: 1.3;
  color: #f5f7f9;
  letter-spacing: -0.02em;
}

.hero-description {
  font-size: 1.1rem;
  margin-bottom: 2rem;
  color: #c1c4c8;
  line-height: 1.85;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 13px 26px;
  border-radius: 14px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

.btn-primary {
  background-color: #3b82e6;
  color: white;
  box-shadow: 0 6px 22px rgba(59, 130, 230, 0.42);
}

.btn-primary:hover {
  background-color: #6ea8f8;
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(59, 130, 230, 0.55);
}

.btn-outline {
  background-color: transparent;
  color: #c1c4c8;
  border-color: #3e485a;
}

.btn-outline:hover {
  border-color: #6ea8f8;
  color: #6ea8f8;
  background-color: rgba(110, 168, 248, 0.08);
}

.hero-image {
  display: flex;
  justify-content: center;
  align-items: center;
}

.app-icon-placeholder {
  width: 200px;
  height: 200px;
  background: transparent;
  border-radius: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow:
    0 18px 60px rgba(59, 130, 230, 0.35),
    0 0 0 1px rgba(255, 255, 255, 0.06);
}

.app-icon-image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: inherit;
}

/* Section Styles */
section {
  padding: 80px 0;
}

.section-title {
  text-align: center;
  font-family: "Inter", "Noto Sans JP", sans-serif;
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 3rem;
  color: #f5f7f9;
  letter-spacing: -0.02em;
}

/* Features Section */
.features {
  background-color: #1f212a;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background: #272f3d;
  padding: 2rem;
  border-radius: 22px;
  border: 1px solid #3e485a;
  text-align: center;
  transition: all 0.3s ease;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.feature-card:hover {
  transform: translateY(-6px);
  border-color: rgba(110, 168, 248, 0.5);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}

.feature-icon {
  margin-bottom: 1.2rem;
}

.icon-placeholder {
  font-size: 2.6rem;
  margin-bottom: 0.5rem;
}

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.8rem;
  color: #f5f7f9;
}

.feature-card p {
  color: #c1c4c8;
  line-height: 1.75;
  font-size: 0.95rem;
}

/* Download Section */
.download {
  background: linear-gradient(135deg, #1f212a 0%, #24304a 100%);
}

.download .section-title {
  color: #f5f7f9;
}

.download-content {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 3rem;
  align-items: center;
}

.download-info h3 {
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: #f5f7f9;
}

.download-info p {
  font-size: 1.05rem;
  margin-bottom: 2rem;
  color: #c1c4c8;
}

.app-store-placeholder {
  display: inline-block;
  height: 52px;
  padding: 0 26px;
  border-radius: 14px;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.3s ease;
  background-color: #3b82e6;
  color: white;
  font-size: 0.95rem;
  line-height: 52px;
  text-align: center;
  box-shadow: 0 6px 22px rgba(59, 130, 230, 0.42);
}

.app-store-placeholder:hover {
  background-color: #6ea8f8;
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(59, 130, 230, 0.55);
}

.download-requirements {
  background-color: #272f3d;
  padding: 2rem;
  border-radius: 18px;
  border: 1px solid #3e485a;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
}

.download-requirements h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: #f5f7f9;
}

.download-requirements ul {
  list-style: none;
}

.download-requirements li {
  padding: 0.6rem 0;
  border-bottom: 1px solid #3e485a;
  color: #c1c4c8;
  font-size: 0.95rem;
}

.download-requirements li:last-child {
  border-bottom: none;
}

/* Privacy Section */
.privacy {
  background-color: #1f212a;
}

.privacy-content {
  max-width: 800px;
  margin: 0 auto;
  background: #272f3d;
  padding: 3rem;
  border-radius: 22px;
  border: 1px solid #3e485a;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
}

.privacy-content h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: #f5f7f9;
}

.privacy-content h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin: 2rem 0 0.8rem;
  color: #f5f7f9;
}

.privacy-content p {
  margin-bottom: 1rem;
  line-height: 1.85;
  color: #c1c4c8;
  font-size: 0.95rem;
}

.privacy-content a {
  color: #6ea8f8;
  text-decoration: none;
}

.privacy-content a:hover {
  text-decoration: underline;
}

.privacy-update {
  font-size: 0.85rem;
  color: #82878c;
  font-style: italic;
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid #3e485a;
}

/* Contact Section */
.contact {
  background-color: #191b22;
}

.contact-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.contact-content > p {
  font-size: 1.05rem;
  margin-bottom: 2rem;
  color: #c1c4c8;
}

.contact-methods {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
}

.contact-method {
  background: #272f3d;
  padding: 2rem;
  border-radius: 22px;
  border: 1px solid #3e485a;
  transition: all 0.3s ease;
  text-align: left;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.contact-method:hover {
  transform: translateY(-4px);
  border-color: rgba(110, 168, 248, 0.5);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}

.contact-method h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.8rem;
  color: #f5f7f9;
}

.contact-method p {
  color: #c1c4c8;
  line-height: 1.7;
  font-size: 0.95rem;
}

.contact-method a {
  color: #6ea8f8;
  text-decoration: none;
  font-weight: 500;
}

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

/* Footer */
.footer {
  background-color: #141620;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding: 2rem 0;
}

.footer-bottom {
  text-align: center;
  color: #82878c;
  font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }

  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 2rem;
  }

  .hero-title {
    font-size: 2.2rem;
  }

  .hero-description {
    font-size: 1rem;
  }

  .hero-buttons {
    justify-content: center;
  }

  .download-content {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .section-title {
    font-size: 1.8rem;
  }

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

  .contact-methods {
    grid-template-columns: 1fr;
  }

  .contact-method {
    text-align: center;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 15px;
  }

  .hero {
    padding: 100px 0 60px;
  }

  .hero-title {
    font-size: 1.9rem;
  }

  .btn {
    padding: 11px 22px;
    font-size: 0.9rem;
  }

  .feature-card {
    padding: 1.5rem;
  }

  .privacy-content {
    padding: 2rem;
  }

  .contact-method {
    padding: 1.5rem;
  }
}

/* Smooth scrolling */
html {
  scroll-behavior: smooth;
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

@keyframes float {
  0%,
  100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-10px);
  }
}

.app-icon-placeholder {
  animation: float 4s ease-in-out infinite;
}