/* =========================================================
   K2C — Advanced Dark / Metallic Blue Design System
   ========================================================= */

:root {
  --bg-void: #050810;
  --bg-panel: #0a0f1c;
  --bg-panel-alt: #0d1428;
  --line: rgba(0, 229, 255, 0.14);
  --line-strong: rgba(0, 229, 255, 0.35);
  --accent: #00e5ff;
  --accent-2: #3d5afe;
  --accent-soft: rgba(0, 229, 255, 0.12);
  --text-main: #eef3f8;
  --text-dim: #8a9bb0;
  --text-faint: #556a82;
  --font-jp: 'Noto Sans JP', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-en: 'Orbitron', var(--font-jp);
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg-void);
  color: var(--text-main);
  font-family: var(--font-jp);
  line-height: 1.7;
  overflow-x: hidden;
  position: relative;
}

a { color: inherit; text-decoration: none; }
ul, dl { margin: 0; padding: 0; }
h1, h2, h3, p { margin: 0; }

/* ---------- Background layers ---------- */
.bg-grid {
  position: fixed;
  inset: 0;
  z-index: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(0,0,0,0.9) 0%, transparent 75%);
  opacity: 0.55;
  pointer-events: none;
}

#particle-canvas {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

.scanline {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: repeating-linear-gradient(
    to bottom,
    rgba(255,255,255,0.015) 0px,
    rgba(255,255,255,0.015) 1px,
    transparent 1px,
    transparent 3px
  );
  opacity: 0.4;
}

/* ---------- Dot-matrix logo ---------- */
.dot-logo {
  display: flex;
  align-items: flex-start;
}
.dot-letter {
  display: grid;
}
.dot-logo .dot {
  width: var(--dot-size);
  height: var(--dot-size);
  margin: calc(var(--dot-gap) / 2);
  background: rgba(0, 229, 255, 0.06);
  border-radius: 2px;
}
.dot-logo .dot.on {
  background: var(--accent);
  box-shadow: 0 0 8px rgba(0, 229, 255, 0.9), 0 0 18px rgba(0, 229, 255, 0.35);
  animation: dotPop 0.5s ease both;
}
@keyframes dotPop {
  from { opacity: 0; transform: scale(0.2); }
  to   { opacity: 1; transform: scale(1); }
}

.brand-mini { line-height: 0; }
.brand-mini .dot-logo .dot { width: 6px; height: 6px; margin: 1px; border-radius: 1px; }

.footer-logo .dot-logo .dot { width: 5px; height: 5px; margin: 1px; border-radius: 1px; }

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(5, 8, 16, 0.7);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
  transition: background 0.3s ease;
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 16px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.main-nav {
  display: flex;
  align-items: center;
  gap: 32px;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}
.main-nav a { transition: color 0.25s ease; position: relative; }
.main-nav a:hover { color: var(--accent); }
.main-nav .nav-cta {
  border: 1px solid var(--line-strong);
  padding: 8px 18px;
  border-radius: 2px;
  color: var(--accent);
}
.main-nav .nav-cta:hover {
  background: var(--accent-soft);
  box-shadow: 0 0 16px rgba(0,229,255,0.25);
}

/* ---------- Layout helpers ---------- */
main { position: relative; z-index: 2; }
.section { padding: 140px 32px; position: relative; }
.section-alt { background: linear-gradient(180deg, transparent, rgba(0,229,255,0.03), transparent); }
.section-inner { max-width: 1100px; margin: 0 auto; }

.section-tag {
  font-family: var(--font-en);
  font-size: 12px;
  letter-spacing: 0.3em;
  color: var(--accent);
  margin-bottom: 18px;
}
.section-title {
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 900;
  letter-spacing: 0.04em;
  margin-bottom: 56px;
  position: relative;
  padding-bottom: 22px;
}
.section-title::after {
  content: '';
  position: absolute;
  left: 0; bottom: 0;
  width: 64px; height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

/* ---------- Hero ---------- */
.hero {
  min-height: 100vh;
  min-height: calc(var(--vh, 1vh) * 100);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 160px 24px 100px;
  position: relative;
}
.hero-inner {
  max-width: 900px;
  position: relative;
  z-index: 2;
}
.eyebrow {
  font-family: var(--font-en);
  font-size: 12px;
  letter-spacing: 0.35em;
  color: var(--text-dim);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-bottom: 48px;
  animation: fadeUp 0.9s ease both;
}
.eyebrow-dot {
  width: 6px; height: 6px;
  background: var(--accent);
  box-shadow: 0 0 10px var(--accent);
  border-radius: 1px;
  animation: blink 1.6s ease-in-out infinite;
}
@keyframes blink { 0%,100% { opacity: 1; } 50% { opacity: 0.25; } }

.hero-title {
  font-size: clamp(30px, 5.4vw, 58px);
  font-weight: 900;
  letter-spacing: 0.03em;
  line-height: 1.4;
  margin-bottom: 28px;
  animation: fadeUp 0.9s ease 0.15s both;
}
.hero-title-sub {
  display: inline-block;
  margin-top: 6px;
  font-size: 0.62em;
  color: var(--accent);
  font-weight: 700;
  letter-spacing: 0.06em;
}
.hero-lead {
  color: var(--text-dim);
  font-size: 16px;
  max-width: 620px;
  margin: 0 auto 48px;
  animation: fadeUp 0.9s ease 0.3s both;
}
.hero-actions {
  display: flex;
  gap: 18px;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeUp 0.9s ease 0.45s both;
}
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(18px); }
  to   { opacity: 1; transform: translateY(0); }
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 15px 34px;
  font-size: 13px;
  letter-spacing: 0.1em;
  border-radius: 2px;
  transition: all 0.25s ease;
  font-weight: 700;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #04101a;
  box-shadow: 0 0 24px rgba(0,229,255,0.35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 30px rgba(0,229,255,0.5); }
.btn-ghost {
  border: 1px solid var(--line-strong);
  color: var(--text-main);
}
.btn-ghost:hover { background: var(--accent-soft); border-color: var(--accent); }

.hero-scroll-cue {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-family: var(--font-en);
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--text-faint);
}
.hero-scroll-cue span {
  width: 1px;
  height: 34px;
  background: linear-gradient(to bottom, var(--accent), transparent);
  animation: scrollCue 1.8s ease-in-out infinite;
}
@keyframes scrollCue {
  0% { transform: scaleY(0.3); opacity: 0.3; }
  50% { transform: scaleY(1); opacity: 1; }
  100% { transform: scaleY(0.3); opacity: 0.3; }
}

/* ---------- Service ---------- */
.service-main { max-width: 720px; margin-bottom: 56px; }
.service-lead {
  font-size: 22px;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 16px;
}
.service-desc { color: var(--text-dim); font-size: 15px; }

.service-grid, .strength-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.service-card, .strength-card {
  background: var(--bg-panel);
  padding: 36px 28px;
  position: relative;
  transition: background 0.3s ease, transform 0.3s ease;
}
.service-card:hover, .strength-card:hover {
  background: var(--bg-panel-alt);
  transform: translateY(-3px);
}

/* Scroll-reveal: start slightly faded/offset, settle once .is-visible is added.
   Never fully hidden, so content is always present even without JS. */
.service-card, .strength-card, .company-row, .contact-form, .service-main {
  opacity: 0.001;
  transform: translateY(18px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.service-card.is-visible, .strength-card.is-visible,
.company-row.is-visible, .contact-form.is-visible, .service-main.is-visible {
  opacity: 1;
  transform: translateY(0);
}
/* If JavaScript never runs, fall back to fully visible via animation. */
@media (scripting: none) {
  .service-card, .strength-card, .company-row, .contact-form, .service-main {
    opacity: 1;
    transform: none;
  }
}
.service-index, .strength-num {
  font-family: var(--font-en);
  font-size: 13px;
  color: var(--accent);
  letter-spacing: 0.15em;
  display: block;
  margin-bottom: 18px;
  opacity: 0.85;
}
.service-card h3, .strength-card h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 12px;
}
.service-card p, .strength-card p {
  font-size: 14px;
  color: var(--text-dim);
}

/* ---------- Company ---------- */
.company-table {
  border-top: 1px solid var(--line);
}
.company-row {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 24px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
}
.company-row dt {
  font-family: var(--font-en);
  font-size: 12px;
  letter-spacing: 0.15em;
  color: var(--text-faint);
  padding-top: 2px;
}
.company-row dd {
  font-size: 15px;
  color: var(--text-main);
}
.company-row a { color: var(--accent); border-bottom: 1px solid transparent; transition: border-color 0.2s ease; }
.company-row a:hover { border-color: var(--accent); }

/* ---------- Contact ---------- */
.section-contact {
  text-align: center;
  background: radial-gradient(ellipse 60% 80% at 50% 30%, rgba(0,229,255,0.08), transparent 70%);
}
.section-contact .section-title::after { left: 50%; transform: translateX(-50%); }
.contact-lead { color: var(--text-dim); margin-bottom: 44px; }

.contact-form {
  max-width: 560px;
  margin: 0 auto;
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 22px;
  padding: 40px;
  border: 1px solid var(--line-strong);
  border-radius: 2px;
  background: rgba(10, 15, 28, 0.5);
}
.form-row {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.form-row label {
  font-size: 13px;
  letter-spacing: 0.05em;
  color: var(--text-dim);
  display: flex;
  align-items: center;
  gap: 8px;
}
.form-row .req {
  font-family: var(--font-en);
  font-size: 10px;
  letter-spacing: 0.05em;
  color: var(--accent);
  border: 1px solid var(--line-strong);
  padding: 2px 6px;
  border-radius: 2px;
}
.form-row input,
.form-row textarea {
  width: 100%;
  background: rgba(5, 8, 16, 0.7);
  border: 1px solid var(--line);
  border-radius: 2px;
  padding: 12px 14px;
  color: var(--text-main);
  font-family: var(--font-jp);
  font-size: 14px;
  transition: border-color 0.25s ease, box-shadow 0.25s ease;
  resize: vertical;
}
.form-row input:focus,
.form-row textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 14px rgba(0,229,255,0.25);
}
.contact-form-submit {
  align-self: flex-start;
  border: none;
  cursor: pointer;
}
.contact-form-note {
  font-size: 12px;
  color: var(--text-faint);
  margin-top: -6px;
}

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 48px 32px;
  position: relative;
  z-index: 2;
}
.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}
.footer-copy {
  font-size: 12px;
  color: var(--text-faint);
  letter-spacing: 0.05em;
}

/* ---------- Responsive ---------- */
@media (max-width: 720px) {
  .header-inner { padding: 14px 20px; }
  .main-nav { gap: 16px; font-size: 11px; }
  .main-nav .nav-cta { padding: 7px 12px; }
  .section { padding: 96px 20px; }
  .br-pc { display: none; }
  .company-row { grid-template-columns: 1fr; gap: 8px; }
  .contact-form { padding: 26px 22px; }
}

@media (max-width: 480px) {
  .main-nav a:not(.nav-cta) { display: none; }
}