@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;700;900&family=Noto+Sans+JP:wght@300;400;700&display=swap');

:root {
  --bg:      #080b12;
  --surface: #0d1120;
  --border:  #1a2540;
  --accent:  #00f0ff;
  --accent2: #ff0080;
  --accent3: #7c3aed;
  --accent4: #00ff88;
  --text:    #e2e8f0;
  --muted:   #64748b;
  --glow:    0 0 20px rgba(0, 240, 255, 0.4);
  --glow2:   0 0 20px rgba(255, 0, 128, 0.4);
  --glow3:   0 0 20px rgba(124, 58, 237, 0.4);
  --glow4:   0 0 20px rgba(0, 255, 136, 0.4);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Noto Sans JP', sans-serif;
  line-height: 1.6;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(0,240,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,240,255,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
  z-index: 0;
}

body::after {
  content: '';
  position: fixed;
  inset: 0;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0,0,0,0.08) 2px,
    rgba(0,0,0,0.08) 4px
  );
  pointer-events: none;
  z-index: 0;
}

/* ── Navigation ── */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2.5rem;
  background: rgba(8, 11, 18, 0.88);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}

.nav-logo {
  font-family: 'Orbitron', monospace;
  font-weight: 900;
  font-size: 1.2rem;
  color: var(--accent);
  text-shadow: var(--glow);
  letter-spacing: 0.15em;
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-family: 'Orbitron', monospace;
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  transition: color 0.2s, text-shadow 0.2s;
  position: relative;
  padding-bottom: 2px;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px; left: 0; right: 0;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transition: transform 0.25s;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--accent);
  text-shadow: var(--glow);
}

.nav-links a.active::after,
.nav-links a:hover::after {
  transform: scaleX(1);
}

/* ── Layout ── */
.wrapper {
  position: relative;
  z-index: 1;
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

section { padding: 5rem 0; }

/* ── Section header ── */
.section-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 3rem;
}

.section-label {
  font-family: 'Orbitron', monospace;
  font-size: 0.65rem;
  letter-spacing: 0.3em;
  color: var(--accent);
  text-transform: uppercase;
}

.section-title {
  font-family: 'Orbitron', monospace;
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text);
}

.section-line {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--border), transparent);
}

/* ── Cards ── */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.75rem;
  position: relative;
  overflow: hidden;
  transition: border-color 0.3s, transform 0.3s;
}

.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  opacity: 0;
  transition: opacity 0.3s;
}

.card:hover { border-color: rgba(0,240,255,0.3); transform: translateY(-4px); }
.card:hover::before { opacity: 1; }

.card-icon { font-size: 2rem; margin-bottom: 1rem; }

.card-title {
  font-family: 'Orbitron', monospace;
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  color: var(--accent);
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.card-body { font-size: 0.9rem; color: var(--muted); line-height: 1.7; }

/* ── Tags ── */
.tag-cloud { display: flex; flex-wrap: wrap; gap: 0.6rem; }

.tag {
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  font-size: 0.72rem;
  font-family: 'Orbitron', monospace;
  letter-spacing: 0.04em;
  border: 1px solid;
  transition: box-shadow 0.2s, transform 0.2s;
  cursor: default;
}
.tag:hover { transform: scale(1.05); }

.tag-cyan   { border-color: var(--accent);  color: var(--accent);  background: rgba(0,240,255,0.06);  }
.tag-pink   { border-color: var(--accent2); color: var(--accent2); background: rgba(255,0,128,0.06);  }
.tag-purple { border-color: var(--accent3); color: #a78bfa;        background: rgba(124,58,237,0.06); }
.tag-green  { border-color: var(--accent4); color: var(--accent4); background: rgba(0,255,136,0.06);  }

.tag-cyan:hover   { box-shadow: var(--glow);  }
.tag-pink:hover   { box-shadow: var(--glow2); }
.tag-purple:hover { box-shadow: var(--glow3); }
.tag-green:hover  { box-shadow: var(--glow4); }

/* ── Buttons ── */
.btn {
  display: inline-block;
  padding: 0.72rem 2rem;
  border-radius: 999px;
  font-family: 'Orbitron', monospace;
  font-size: 0.78rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  text-decoration: none;
  background: linear-gradient(135deg, var(--accent), var(--accent3));
  color: var(--bg);
  font-weight: 700;
  box-shadow: 0 0 28px rgba(0,240,255,0.25);
  transition: box-shadow 0.3s, transform 0.2s;
  cursor: pointer;
  border: none;
}

.btn:hover { box-shadow: 0 0 48px rgba(0,240,255,0.5); transform: scale(1.04); }

.btn-outline {
  background: transparent;
  border: 1px solid var(--accent);
  color: var(--accent);
  box-shadow: none;
}
.btn-outline:hover { background: rgba(0,240,255,0.08); box-shadow: var(--glow); transform: scale(1.04); }

/* ── Page intro (Skills / Contact pages) ── */
.page-intro {
  padding: 9rem 0 4rem;
  text-align: center;
}

.page-intro-label {
  font-family: 'Orbitron', monospace;
  font-size: 0.7rem;
  letter-spacing: 0.3em;
  color: var(--accent);
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}

.page-intro-title {
  font-family: 'Orbitron', monospace;
  font-size: clamp(2.2rem, 7vw, 4rem);
  font-weight: 900;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent3) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1.1;
  margin-bottom: 0.75rem;
}

.page-intro-sub {
  color: var(--muted);
  font-size: 0.95rem;
  max-width: 480px;
  margin: 0 auto;
  line-height: 1.8;
}

/* ── Footer ── */
footer {
  position: relative;
  z-index: 1;
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  text-align: center;
}

footer p {
  font-size: 0.78rem;
  color: var(--muted);
  font-family: 'Orbitron', monospace;
  letter-spacing: 0.1em;
}

/* ── Responsive ── */
@media (max-width: 640px) {
  nav { padding: 1rem 1.25rem; }
  .nav-links { gap: 1.2rem; }
  .nav-links a { font-size: 0.72rem; }
  section { padding: 3.5rem 0; }
}