/*--------------------------------------------------------------
あのあれ - カタカナ禁止のパーティーゲーム
モダンランディングページ CSS
--------------------------------------------------------------*/

/*--------------------------------------------------------------
1.0 VARIABLES & FOUNDATION
--------------------------------------------------------------*/

:root {
  /* Colors */
  --primary-color: #FF6B35;
  --primary-dark: #E55A2B;
  --secondary-color: #4ECDC4;
  --accent-color: #FFE66D;
  --background-primary: #FFF8F0;
  --background-secondary: #FFFFFF;
  --text-primary: #2C3E50;
  --text-secondary: #7F8C8D;
  --text-light: #BDC3C7;
  --success-color: #27AE60;
  --border-color: #E8E8E8;
  
  /* Typography */
  --font-family: 'Noto Sans JP', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  --spacing-4xl: 6rem;
  
  /* Border radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  /* Container */
  --container-max-width: 1200px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--background-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.ui-layout-container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

/* Common utilities */
.text-center { text-align: center; }
.font-bold { font-weight: 700; }
.font-normal { font-weight: 400; }

/*--------------------------------------------------------------
2.0 HEADER
--------------------------------------------------------------*/

.ui-section-header {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  border-bottom: 1px solid var(--border-color);
  padding: var(--spacing-md) 0;
}

.ui-section-header__layout {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 700;
  font-size: var(--font-size-xl);
  transition: opacity 0.3s ease;
}

.header-logo:hover {
  opacity: 0.8;
}

.logo-text {
  font-size: var(--font-size-xl);
  font-weight: 900;
  color: var(--primary-color);
}

.header-contact .contact-link {
  color: var(--text-secondary);
  text-decoration: none;
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-full);
  transition: all 0.3s ease;
}

.header-contact .contact-link:hover {
  background-color: var(--primary-color);
  color: white;
}

/*--------------------------------------------------------------
3.0 HERO SECTION
--------------------------------------------------------------*/

.ui-section-hero {
  padding: calc(80px + var(--spacing-4xl)) 0 var(--spacing-4xl);
  background: linear-gradient(135deg, var(--background-primary) 0%, #FFF5E6 100%);
  overflow: hidden;
  position: relative;
}

.ui-section-hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: 
    radial-gradient(circle at 25% 25%, var(--accent-color) 0%, transparent 50%),
    radial-gradient(circle at 75% 75%, var(--secondary-color) 0%, transparent 50%);
  opacity: 0.1;
  z-index: 1;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-3xl);
  align-items: center;
  position: relative;
  z-index: 2;
}

.hero-badge {
  display: inline-block;
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-full);
  font-size: var(--font-size-sm);
  font-weight: 600;
  margin-bottom: var(--spacing-lg);
  box-shadow: var(--shadow-md);
}

.hero-title {
  font-size: var(--font-size-4xl);
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: var(--spacing-lg);
  color: var(--text-primary);
}

.hero-title .highlight {
  color: var(--primary-color);
  position: relative;
}

.hero-title .highlight::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 0.3em;
  background: linear-gradient(90deg, var(--accent-color), var(--secondary-color));
  z-index: -1;
  border-radius: var(--radius-sm);
}

.hero-description {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  line-height: 1.7;
}

.hero-features {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.feature-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  background: white;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  font-weight: 500;
  color: var(--text-primary);
}

.feature-icon {
  font-size: var(--font-size-lg);
}

.hero-cta {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.hero-image {
  text-align: center;
}

.hero-phone {
  max-width: 300px;
  width: 100%;
  height: auto;
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-xl);
  transform: perspective(1000px) rotateY(-5deg) rotateX(5deg);
  transition: transform 0.3s ease;
}

.hero-phone:hover {
  transform: perspective(1000px) rotateY(0deg) rotateX(0deg) scale(1.05);
}

/*--------------------------------------------------------------
4.0 DOWNLOAD BUTTON
--------------------------------------------------------------*/

.download-button {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  text-decoration: none;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: var(--font-size-base);
  box-shadow: var(--shadow-md);
  transition: all 0.3s ease;
  border: none;
  cursor: pointer;
}

.download-button:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  background: linear-gradient(135deg, var(--primary-dark), #D14A1F);
}

.download-button.large {
  padding: var(--spacing-lg) var(--spacing-2xl);
  font-size: var(--font-size-lg);
  min-width: 280px;
}

.download-button.secondary {
  background: linear-gradient(135deg, #4CAF50, #388E3C);
}

.download-button.secondary:hover {
  background: linear-gradient(135deg, #388E3C, #2E7D32);
}

.download-buttons {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  align-items: center;
  margin-bottom: var(--spacing-lg);
}

.download-note {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  text-align: center;
  margin: 0;
}

/*--------------------------------------------------------------
5.0 SECTIONS
--------------------------------------------------------------*/

.ui-section-howto,
.ui-section-features,
.ui-section-cta {
  padding: var(--spacing-4xl) 0;
}

.ui-section-howto {
  background: white;
}

.ui-section-features {
  background: var(--background-primary);
}

.ui-section-cta {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
}

.section-title {
  font-size: var(--font-size-3xl);
  font-weight: 900;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

.ui-section-cta .section-title {
  color: white;
}

.section-subtitle {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin: 0;
}

/*--------------------------------------------------------------
6.0 HOW TO PLAY SECTION
--------------------------------------------------------------*/

.howto-steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-4xl);
}

.step-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  max-width: 400px;
  margin: 0 auto;
}

.step-number {
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-2xl);
  font-weight: 900;
  box-shadow: var(--shadow-lg);
  margin-bottom: var(--spacing-lg);
  position: relative;
  z-index: 2;
}

.step-content {
  width: 100%;
}

.step-content h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
}

.step-content p {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-lg);
  line-height: 1.6;
}

.step-image {
  max-width: 280px;
  width: 100%;
  height: auto;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.step-image:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-xl);
}

/*--------------------------------------------------------------
7.0 FEATURES SECTION
--------------------------------------------------------------*/

.features-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-xl);
}

.feature-card {
  background: white;
  padding: var(--spacing-xl);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  text-align: center;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.feature-icon-large {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
}

.feature-card h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
}

.feature-card p {
  color: var(--text-secondary);
  margin: 0;
}

/*--------------------------------------------------------------
8.0 CTA SECTION
--------------------------------------------------------------*/

.cta-content {
  text-align: center;
  max-width: 700px;
  margin: 0 auto;
}

.cta-title {
  font-size: var(--font-size-3xl);
  font-weight: 900;
  margin-bottom: var(--spacing-md);
  color: white;
}

.cta-description {
  font-size: var(--font-size-lg);
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--spacing-xl);
}

.cta-buttons {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
}

.ui-section-cta .download-note {
  color: rgba(255, 255, 255, 0.8);
  font-weight: 500;
}

/*--------------------------------------------------------------
9.0 FOOTER
--------------------------------------------------------------*/

.ui-section-footer {
  background: var(--text-primary);
  color: white;
  padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.footer-app-name {
  font-size: var(--font-size-xl);
  font-weight: 900;
  color: var(--primary-color);
}

.footer-description {
  color: rgba(255, 255, 255, 0.8);
  margin: 0;
}

.footer-contact h4 {
  margin-bottom: var(--spacing-md);
  color: var(--primary-color);
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.contact-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  transition: color 0.3s ease;
}

.contact-item:hover {
  color: var(--primary-color);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--spacing-md);
  text-align: center;
}

.copyright {
  color: rgba(255, 255, 255, 0.6);
  font-size: var(--font-size-sm);
  margin: 0;
}

/*--------------------------------------------------------------
10.0 RESPONSIVE DESIGN
--------------------------------------------------------------*/

@media (min-width: 640px) {
  .hero-features {
    justify-content: center;
  }
  
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .cta-buttons {
    flex-direction: row;
    justify-content: center;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
  }
}

@media (min-width: 768px) {
  .ui-layout-container {
    padding: 0 var(--spacing-xl);
  }
  
  .hero-content {
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-4xl);
  }
  
  .hero-title {
    font-size: var(--font-size-5xl);
  }
  
  .howto-steps {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-2xl);
  }
  
  .step-item {
    max-width: none;
  }
  
  .download-buttons {
    flex-direction: row;
    gap: var(--spacing-lg);
    justify-content: center;
  }
  
  .cta-buttons {
    flex-direction: row;
    justify-content: center;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
  }
  
  .footer-content {
    grid-template-columns: 2fr 1fr;
    align-items: start;
  }
}

@media (min-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(4, 1fr);
  }
  
  .howto-steps {
    gap: var(--spacing-4xl);
  }
}

@media (min-width: 1200px) {
  .ui-layout-container {
    padding: 0 var(--spacing-2xl);
  }
}