/* ==========================================
   DESIGN VARIABLES
=========================================== */
:root {
  --bg-main: #0b0d0e;
  --bg-card: #141719;
  --bg-alt: #111315;
  --accent-color: #10b981;
  --accent-hover: #059669;
  --text-primary: #f3f4f6;
  --text-secondary: #9ca3af;
  --border-color: #27272a;
  
  --font-base: 'Noto Sans JP', sans-serif;
  --font-heading: 'Cinzel', 'Noto Sans JP', sans-serif;
  
  --container-width: 1200px;
  --section-padding: 100px 20px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-base);
  background-color: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.8;
  letter-spacing: 0.05em;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
  transition: opacity 0.3s ease;
}

a:hover {
  opacity: 0.8;
}

ul {
  list-style: none;
}

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* HEADER */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(11, 13, 14, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}

.header-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 15px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav ul {
  display: flex;
  gap: 25px;
}

.nav a {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  letter-spacing: 0.15em;
  color: var(--text-secondary);
}

.nav a:hover {
  color: var(--text-primary);
}

/* BUTTONS */
.btn {
  display: inline-block;
  padding: 12px 30px;
  border-radius: 2px;
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  transition: all 0.3s ease;
  text-align: center;
}

.btn-primary {
  background-color: var(--text-primary);
  color: var(--bg-main);
}

.btn-primary:hover {
  background-color: var(--accent-color);
  color: #fff;
}

.btn-sm {
  padding: 6px 16px;
  font-size: 0.75rem;
  border: 1px solid var(--text-primary);
}

/* HERO */
.hero {
  position: relative;
  height: 90vh;
  min-height: 600px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, rgba(11,13,14,0.4) 0%, rgba(11,13,14,1) 100%);
  z-index: 2;
}

.hero-content {
  position: relative;
  z-index: 3;
  max-width: 800px;
  padding: 0 20px;
}

.hero-sub {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  letter-spacing: 0.3em;
  color: var(--accent-color);
  margin-bottom: 15px;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  margin-bottom: 20px;
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 35px;
}

/* SECTION */
.section {
  padding: var(--section-padding);
}

.bg-alt {
  background-color: var(--bg-alt);
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-subtitle {
  font-family: var(--font-heading);
  font-size: 0.8rem;
  letter-spacing: 0.25em;
  color: var(--accent-color);
  display: block;
  margin-bottom: 10px;
}

.section-title {
  font-size: 2rem;
  font-weight: 500;
  letter-spacing: 0.08em;
}

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

.lead-text {
  font-size: 1.05rem;
  color: var(--text-primary);
  line-height: 2;
}

/* FEATURES GRID */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.feature-card {
  background-color: var(--bg-card);
  padding: 30px 20px;
  border: 1px solid var(--border-color);
  border-radius: 4px;
}

.feature-card.border-accent {
  border-left: 3px solid var(--accent-color);
}

.feature-card h4 {
  font-size: 1.1rem;
  margin-bottom: 15px;
  color: var(--text-primary);
}

.feature-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* DOWNLOAD & COMPANY GRID */
.company-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
  margin: 0 auto;
}

.download-box {
  background-color: var(--bg-card);
  padding: 40px;
  border: 1px solid var(--border-color);
  border-radius: 4px;
}

.store-label {
  font-size: 0.9rem;
  margin-bottom: 10px;
  color: var(--text-secondary);
}

/* FOOTER */
.footer {
  padding: 40px 20px;
  text-align: center;
  border-top: 1px solid var(--border-color);
  background-color: var(--bg-main);
}

.copyright {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

@media (max-width: 768px) {
  .nav {
    display: none;
  }
  :root {
    --section-padding: 60px 20px;
  }
}