/* ═══════════════════════════════════════
   SIGNALIA — Homepage Styles
   APS Payroll 스타일 레퍼런스: 딥 틸 + 라임 그린
   ═══════════════════════════════════════ */

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

:root {
  /* ── 컬러 팔레트 (딥 틸-네이비 + 라임 그린) ── */
  --bg:             #021c28;
  --bg-2:           #031f2e;
  --bg-3:           #042636;
  --surface:        #063040;
  --surface-2:      #083a4c;
  --line:           #0d4258;
  --line-bright:    #185a70;
  --text-primary:   #e4f2f8;
  --text-secondary: #4e7f98;
  --text-dim:       #0e3a50;
  --accent:         #c8ff5c;   /* 라임 그린 */
  --accent-dark:    #a0d640;
  --accent-dim:     rgba(200, 255, 92, 0.08);
  --accent-glow:    rgba(200, 255, 92, 0.18);

  --font-mono: 'JetBrains Mono', monospace;
  --font-sans: 'Inter', sans-serif;

  --t-fast: 130ms;
  --t-mid:  260ms;
  --t-slow: 500ms;

  --max-w: 1160px;
  --nav-h: 68px;
}

/* ── 기본 ── */

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* 미묘한 틸 그리드 */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: 0.3;
  pointer-events: none;
  z-index: 0;
}

/* ══════════════════════════════
   Navigation
══════════════════════════════ */

.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--nav-h);
  transition: background var(--t-mid), border-color var(--t-mid);
  border-bottom: 1px solid transparent;
}

.nav.scrolled {
  background: rgba(2, 28, 40, 0.95);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-color: var(--line);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  height: 100%;
  padding: 0 48px;
  display: flex;
  align-items: center;
  gap: 48px;
  position: relative;
  z-index: 1;
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 500;
  letter-spacing: 0.3em;
  color: var(--text-primary);
  text-decoration: none;
  flex-shrink: 0;
}

.nav-logo span { color: var(--accent); }

.nav-links {
  display: flex;
  gap: 36px;
  margin-left: auto;
}

.nav-link {
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 400;
  color: var(--text-secondary);
  text-decoration: none;
  letter-spacing: 0.02em;
  transition: color var(--t-fast);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px; left: 0; right: 0;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transition: transform var(--t-fast);
}

.nav-link:hover { color: var(--text-primary); }
.nav-link:hover::after { transform: scaleX(1); }

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.lang-toggle {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--text-secondary);
  background: none;
  border: 1px solid var(--line-bright);
  padding: 6px 12px;
  cursor: pointer;
  transition: color var(--t-fast), border-color var(--t-fast);
}

.lang-toggle:hover {
  color: var(--accent);
  border-color: var(--accent);
}

.btn-nav-cta {
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--bg);
  background: var(--accent);
  border: none;
  padding: 10px 22px;
  text-decoration: none;
  border-radius: 2px;
  transition: background var(--t-fast), transform var(--t-fast);
}

.btn-nav-cta:hover {
  background: var(--accent-dark);
  transform: translateY(-1px);
}

.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  margin-left: auto;
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--text-secondary);
  transition: background var(--t-fast);
}

.nav-hamburger:hover span { background: var(--text-primary); }

.nav-mobile {
  display: none;
  flex-direction: column;
  background: rgba(2, 28, 40, 0.98);
  border-top: 1px solid var(--line);
  padding: 28px 48px;
  gap: 22px;
}

.nav-mobile.is-open { display: flex; }

.nav-mobile-link {
  font-size: 14px;
  font-weight: 400;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color var(--t-fast);
}

.nav-mobile-link:hover { color: var(--accent); }

/* ══════════════════════════════
   Hero
══════════════════════════════ */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: radial-gradient(ellipse 80% 60% at 50% 0%, #063a52 0%, var(--bg) 65%);
}

.hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  opacity: 0.7;
}

/* 하단 페이드 */
.hero::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 240px;
  background: linear-gradient(transparent, var(--bg));
  z-index: 1;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 160px 48px 100px;
  width: 100%;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.35em;
  color: var(--accent);
  margin-bottom: 36px;
  text-transform: uppercase;
  animation: fadeUp 0.9s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--accent);
}

.hero-title {
  font-family: var(--font-mono);
  font-size: clamp(48px, 7.5vw, 104px);
  font-weight: 300;
  line-height: 1.02;
  letter-spacing: -0.035em;
  color: var(--text-primary);
  margin-bottom: 32px;
  animation: fadeUp 0.9s 0.08s cubic-bezier(0.16, 1, 0.3, 1) both;
}

/* 라임 강조 단어 */
.hero-title .hl {
  font-style: normal;
  color: var(--accent);
}

.hero-sub {
  font-size: 17px;
  font-weight: 300;
  line-height: 1.9;
  color: var(--text-secondary);
  max-width: 560px;
  margin-bottom: 48px;
  animation: fadeUp 0.9s 0.16s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.hero-cta {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 48px;
  animation: fadeUp 0.9s 0.24s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.btn-primary {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--bg);
  background: var(--accent);
  border: 2px solid var(--accent);
  padding: 15px 38px;
  text-decoration: none;
  border-radius: 2px;
  transition: background var(--t-fast), transform var(--t-fast);
}

.btn-primary:hover {
  background: var(--accent-dark);
  border-color: var(--accent-dark);
  transform: translateY(-2px);
}

.btn-secondary {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--text-primary);
  background: transparent;
  border: 2px solid var(--line-bright);
  padding: 15px 38px;
  text-decoration: none;
  border-radius: 2px;
  transition: border-color var(--t-fast), color var(--t-fast), transform var(--t-fast);
}

.btn-secondary:hover {
  border-color: var(--text-primary);
  transform: translateY(-2px);
}

.hero-badges {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  animation: fadeUp 0.9s 0.32s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.badge {
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 500;
  letter-spacing: 0.2em;
  color: var(--text-secondary);
  border: 1px solid var(--line-bright);
  padding: 5px 12px;
  background: rgba(6, 48, 64, 0.6);
  text-transform: uppercase;
}

.hero-scroll-hint {
  position: absolute;
  bottom: 48px;
  right: 48px;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  animation: fadeUp 1s 0.5s both;
}

.scroll-line {
  width: 1px;
  height: 52px;
  background: linear-gradient(to bottom, var(--accent), transparent);
  animation: scrollPulse 2.4s ease-in-out infinite;
}

.hero-scroll-hint span {
  font-family: var(--font-mono);
  font-size: 8px;
  letter-spacing: 0.35em;
  color: var(--text-dim);
  text-transform: uppercase;
  writing-mode: vertical-rl;
}

/* ══════════════════════════════
   공통 섹션
══════════════════════════════ */

.sig-section {
  position: relative;
  z-index: 1;
  padding: 128px 48px;
  border-top: 1px solid var(--line);
}

.sig-section--dark {
  background: var(--bg-2);
}

/* 섹션 측면 장식선 */
.sig-section::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 3px;
  background: linear-gradient(to bottom, var(--accent), transparent 60%);
  opacity: 0;
  transition: opacity var(--t-slow);
}

.sig-section:hover::before { opacity: 0.5; }

.sig-inner {
  max-width: var(--max-w);
  margin: 0 auto;
}

.sig-inner--narrow {
  max-width: 760px;
}

.sig-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 36px;
}

.sig-num {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-dim);
  letter-spacing: 0.15em;
  font-weight: 400;
}

.sig-tag {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 500;
  letter-spacing: 0.4em;
  color: var(--accent);
  text-transform: uppercase;
}

.sig-title {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.2vw, 56px);
  font-weight: 300;
  line-height: 1.12;
  letter-spacing: -0.025em;
  color: var(--text-primary);
  margin-bottom: 24px;
}

.sig-desc {
  font-size: 16px;
  font-weight: 300;
  line-height: 1.9;
  color: var(--text-secondary);
  margin-bottom: 72px;
  max-width: 600px;
}

/* ══════════════════════════════
   Vision — 카드 그리드
══════════════════════════════ */

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  padding: 44px 36px;
  position: relative;
  overflow: hidden;
  transition: border-color var(--t-mid), background var(--t-mid), transform var(--t-mid);
}

.card:hover {
  background: var(--surface-2);
  border-color: var(--line-bright);
  transform: translateY(-4px);
}

/* 카드 상단 라임 강조선 */
.card-accent-line {
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t-mid);
}

.card:hover .card-accent-line { transform: scaleX(1); }

.card-icon {
  display: block;
  font-size: 20px;
  color: var(--accent);
  margin-bottom: 24px;
  opacity: 0.8;
}

.card-title {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 16px;
  letter-spacing: 0.01em;
}

.card-text {
  font-size: 14px;
  font-weight: 300;
  line-height: 1.85;
  color: var(--text-secondary);
}

/* ══════════════════════════════
   Technology — 리스트
══════════════════════════════ */

.tech-list {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line);
}

.tech-item {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 48px;
  padding: 60px 0;
  border-bottom: 1px solid var(--line);
  transition: background var(--t-mid);
  cursor: default;
}

.tech-item:hover {
  background: linear-gradient(90deg, var(--accent-dim), transparent 50%);
}

.tech-num {
  font-family: var(--font-mono);
  font-size: 40px;
  font-weight: 300;
  color: var(--text-dim);
  letter-spacing: -0.04em;
  line-height: 1;
  padding-top: 4px;
  transition: color var(--t-mid);
}

.tech-item:hover .tech-num { color: var(--accent); }

.tech-title {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.tech-subtitle {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 500;
  letter-spacing: 0.3em;
  color: var(--accent);
  margin-bottom: 20px;
  text-transform: uppercase;
}

.tech-desc {
  font-size: 15px;
  font-weight: 300;
  line-height: 1.9;
  color: var(--text-secondary);
  margin-bottom: 28px;
  max-width: 680px;
}

.tech-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag-chip {
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--accent);
  border: 1px solid rgba(200, 255, 92, 0.25);
  padding: 5px 12px;
  background: var(--accent-dim);
  text-transform: uppercase;
}

/* ══════════════════════════════
   Applications
══════════════════════════════ */

.app-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.app-item {
  background: var(--surface);
  border: 1px solid var(--line);
  padding: 44px 36px;
  position: relative;
  overflow: hidden;
  transition: border-color var(--t-mid), transform var(--t-mid);
}

.app-item::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 3px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t-mid);
}

.app-item:hover {
  border-color: var(--line-bright);
  transform: translateY(-4px);
}

.app-item:hover::after { transform: scaleX(1); }

.app-icon-wrap {
  color: var(--accent);
  margin-bottom: 28px;
  opacity: 0.75;
}

.app-title {
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 16px;
  letter-spacing: 0.01em;
}

.app-desc {
  font-size: 14px;
  font-weight: 300;
  line-height: 1.85;
  color: var(--text-secondary);
}

/* ══════════════════════════════
   Contact Form
══════════════════════════════ */

.contact-form {
  display: flex;
  flex-direction: column;
  gap: 22px;
  margin-top: 52px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.form-label {
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 500;
  letter-spacing: 0.35em;
  color: var(--text-secondary);
  text-transform: uppercase;
}

.form-input {
  background: var(--surface);
  border: 1px solid var(--line-bright);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 300;
  padding: 14px 18px;
  outline: none;
  width: 100%;
  border-radius: 2px;
  appearance: none;
  -webkit-appearance: none;
  transition: border-color var(--t-fast), background var(--t-fast);
}

.form-input::placeholder { color: var(--text-dim); }

.form-input:focus {
  border-color: var(--accent);
  background: var(--surface-2);
}

.form-select { cursor: pointer; color: var(--text-primary); }
.form-select option { background: var(--surface); }
.form-textarea { resize: vertical; min-height: 130px; }

.form-status {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  min-height: 18px;
  transition: color var(--t-fast);
}

.form-status.ok  { color: var(--accent); }
.form-status.err { color: #f05050; }

.btn-submit {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--bg);
  background: var(--accent);
  border: none;
  padding: 16px 48px;
  cursor: pointer;
  border-radius: 2px;
  align-self: flex-start;
  transition: background var(--t-fast), transform var(--t-fast);
}

.btn-submit:hover {
  background: var(--accent-dark);
  transform: translateY(-2px);
}

.btn-submit:disabled { opacity: 0.4; cursor: not-allowed; transform: none; }

/* ══════════════════════════════
   Footer
══════════════════════════════ */

.footer {
  position: relative;
  z-index: 1;
  border-top: 1px solid var(--line);
  padding: 40px 48px;
  background: var(--bg-2);
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-logo {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.35em;
  color: var(--accent);
}

.footer-copy {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  color: var(--text-dim);
}

/* ══════════════════════════════
   애니메이션
══════════════════════════════ */

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(28px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.25; transform: scaleY(1); }
  50%       { opacity: 1;    transform: scaleY(1.1); }
}

/* ── Scroll Reveal ── */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.75s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.75s cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ══════════════════════════════
   반응형
══════════════════════════════ */

@media (max-width: 960px) {
  .nav-links, .btn-nav-cta { display: none; }
  .nav-hamburger { display: flex; }
  .lang-toggle   { margin-left: auto; }
  .nav-inner     { padding: 0 28px; }
  .nav-mobile    { padding: 24px 28px; }

  .card-grid  { grid-template-columns: 1fr; gap: 14px; }
  .app-grid   { grid-template-columns: 1fr 1fr; }
  .form-row   { grid-template-columns: 1fr; }

  .tech-item  { grid-template-columns: 56px 1fr; gap: 24px; padding: 44px 0; }
  .tech-num   { font-size: 26px; }
  .tech-title { font-size: 20px; }

  .sig-section   { padding: 88px 28px; }
  .hero-content  { padding: 120px 28px 80px; }
  .footer        { padding: 32px 28px; }
}

@media (max-width: 640px) {
  .hero-title  { font-size: 42px; }
  .sig-title   { font-size: 28px; }
  .app-grid    { grid-template-columns: 1fr; }
  .hero-cta    { flex-direction: column; align-items: flex-start; }
  .btn-submit  { width: 100%; text-align: center; }
}