:root {
  --color-bg: #0f172a;
  --color-text: #f8fafc;
  --color-primary: #06b6d4;
  /* Cyan */
  --color-secondary: #d946ef;
  /* Fuchsia */
  --color-accent: #f59e0b;
  /* Amber */
  --font-main: 'Inter', 'Noto Sans JP', sans-serif;

  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 32px;
  --spacing-xl: 64px;
}

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

body {
  font-family: var(--font-main);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
}

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

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: var(--spacing-md) var(--spacing-xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(15, 23, 42, 0.8);
  backdrop-filter: blur(12px);
  z-index: 1000;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.logo {
  font-weight: 900;
  font-size: 1.5rem;
  letter-spacing: -0.05em;
}

.version {
  color: var(--color-primary);
}

.nav {
  display: flex;
  gap: var(--spacing-lg);
  align-items: center;
}

.nav a,
.nav-item>a {
  font-weight: 700;
  font-size: 0.9rem;
  transition: color 0.3s;
}

.nav a:hover,
.nav-item>a:hover {
  color: var(--color-primary);
}

/* Dropdown */
.nav-item {
  position: relative;
  display: flex;
  align-items: center;
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  background: rgba(15, 23, 42, 0.9);
  backdrop-filter: blur(12px);
  padding: var(--spacing-sm) 0;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  min-width: 200px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5);
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  pointer-events: none;
}

.nav-item:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
  pointer-events: auto;
}

.dropdown-menu a {
  display: block;
  padding: var(--spacing-sm) var(--spacing-md);
  white-space: nowrap;
  font-size: 0.85rem;
  color: var(--color-text);
  text-decoration: none;
}

.dropdown-menu a:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--color-primary);
}

.btn-contact {
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--color-text);
  border-radius: 999px;
  transition: all 0.3s;
}

.btn-contact:hover {
  background: var(--color-text);
  color: var(--color-bg);
}

/* Hero Section */
.hero {
  position: relative;
  height: 100vh;
  display: flex;
  align-items: center;
  padding: 0 var(--spacing-xl);
  overflow: hidden;
}

/* Background image will be set via JS or inline for now as we setup assets */
.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('./assets/hero-bg.png') no-repeat center center/cover;
  opacity: 0.6;
  z-index: -1;
}

.hero-content {
  z-index: 1;
  max-width: 800px;
}

.hero-title {
  font-size: 5rem;
  line-height: 1.1;
  font-weight: 900;
  margin-bottom: var(--spacing-md);
  letter-spacing: -0.02em;
}

.text-gradient {
  background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.25rem;
  margin-bottom: var(--spacing-lg);
  max-width: 600px;
  color: rgba(255, 255, 255, 0.8);
}

.hero-actions {
  display: flex;
  gap: var(--spacing-md);
}

.btn-primary,
.btn-secondary {
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: 4px;
  /* More techy/sharp */
  font-weight: 700;
  cursor: pointer;
  border: none;
  font-size: 1rem;
  transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-bg);
  box-shadow: 0 0 20px rgba(6, 182, 212, 0.5);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(6, 182, 212, 0.7);
}

.btn-secondary {
  background: transparent;
  border: 1px solid var(--color-secondary);
  color: var(--color-secondary);
}

.btn-secondary:hover {
  background: rgba(217, 70, 239, 0.1);
  box-shadow: 0 0 20px rgba(217, 70, 239, 0.3);
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 3rem;
  }
}