/* ===== McKinsey-Style Design System ===== */
/* Black + White + #BD001D only. Maximum whitespace. Minimal decoration. */

:root {
  --black: #000000;
  --dark: #1A1A1A;
  --text: #333333;
  --text-light: #666666;
  --text-muted: #999999;
  --white: #FFFFFF;
  --off-white: #F9F9F9;
  --border: #E5E5E5;
  --red: #BD001D;
  --red-light: #D4263A;
  --sans: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --serif: 'Noto Serif SC', Georgia, serif;
}

*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior:smooth; font-size:16px; }
body {
  font-family: var(--sans);
  line-height: 1.8;
  color: var(--text);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}
a { text-decoration:none; color:inherit; transition:color .2s; }
img { max-width:100%; height:auto; }
ul { list-style:none; }

/* ===== Layout ===== */
.container { max-width:1200px; margin:0 auto; padding:0 48px; }
.container-narrow { max-width:860px; margin:0 auto; padding:0 48px; }

/* ===== Navigation ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--white);
  border-bottom: 1px solid transparent;
  transition: border-color .3s;
}
.nav.scrolled { border-bottom-color: var(--border); }
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.nav-logo img { height: 32px; width: auto; }
.nav-links { display:flex; gap:32px; align-items:center; }
.nav-links a {
  font-size: 14px;
  color: var(--text);
  font-weight: 400;
  padding: 4px 0;
  position: relative;
}
.nav-links a:hover { color: var(--red); }
.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 1.5px;
  background: var(--red);
}
.nav-cta {
  font-size: 14px !important;
  color: var(--red) !important;
  font-weight: 500 !important;
  border: 1px solid var(--red);
  padding: 6px 20px !important;
  border-radius: 0;
  transition: all .2s !important;
}
.nav-cta:hover {
  background: var(--red) !important;
  color: var(--white) !important;
}
.nav-mobile-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--text);
}

/* ===== Hero ===== */
.hero {
  min-height: 85vh;
  display: flex;
  align-items: flex-end;
  position: relative;
  padding: 0 0 80px;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, rgba(0,0,0,.2) 0%, rgba(0,0,0,.6) 100%);
}
.hero-content {
  position: relative;
  z-index: 1;
  color: var(--white);
  max-width: 800px;
}
.hero-label {
  font-size: 13px;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: rgba(255,255,255,.7);
  margin-bottom: 24px;
  font-weight: 400;
}
.hero h1 {
  font-size: 56px;
  font-weight: 300;
  line-height: 1.15;
  letter-spacing: -1px;
  margin-bottom: 24px;
}
.hero h1 strong {
  font-weight: 600;
}
.hero-desc {
  font-size: 18px;
  line-height: 1.8;
  color: rgba(255,255,255,.8);
  max-width: 560px;
  margin-bottom: 40px;
}
.hero-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--white);
  border-bottom: 1px solid var(--white);
  padding-bottom: 4px;
  transition: all .2s;
}
.hero-btn:hover {
  color: var(--red-light);
  border-bottom-color: var(--red-light);
}

/* ===== Page Header (sub pages) ===== */
.page-header {
  padding: 160px 0 80px;
  border-bottom: 1px solid var(--border);
}
.page-header h1 {
  font-size: 48px;
  font-weight: 300;
  letter-spacing: -0.5px;
  line-height: 1.2;
  margin-bottom: 16px;
  color: var(--black);
}
.page-header p {
  font-size: 18px;
  color: var(--text-light);
  max-width: 600px;
  line-height: 1.8;
}

/* ===== Section ===== */
.section { padding: 120px 0; }
.section-border { border-bottom: 1px solid var(--border); }
.section-gray { background: var(--off-white); }

.section-label {
  font-size: 12px;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--red);
  font-weight: 500;
  margin-bottom: 20px;
}
.section-title {
  font-size: 36px;
  font-weight: 300;
  color: var(--black);
  line-height: 1.3;
  letter-spacing: -0.5px;
  margin-bottom: 24px;
}
.section-title strong { font-weight: 600; }
.section-desc {
  font-size: 17px;
  color: var(--text-light);
  line-height: 1.9;
  max-width: 640px;
}

/* ===== Stat Row ===== */
.stat-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
}
.stat-item {
  padding: 48px 32px;
  border-right: 1px solid var(--border);
  text-align: center;
}
.stat-item:last-child { border-right: none; }
.stat-num {
  font-size: 48px;
  font-weight: 300;
  color: var(--black);
  line-height: 1;
  margin-bottom: 8px;
  letter-spacing: -1px;
}
.stat-num span { font-size: 20px; font-weight: 400; }
.stat-label {
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.5px;
}

/* ===== Feature Grid ===== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
}
.feature-item {
  padding: 64px 48px;
  border-bottom: 1px solid var(--border);
  border-right: 1px solid var(--border);
  transition: background .3s;
}
.feature-item:nth-child(2n) { border-right: none; }
.feature-item:nth-last-child(-n+2) { border-bottom: none; }
.feature-item:hover { background: var(--off-white); }
.feature-num {
  font-size: 13px;
  color: var(--red);
  font-weight: 500;
  margin-bottom: 16px;
  letter-spacing: 1px;
}
.feature-item h3 {
  font-size: 22px;
  font-weight: 500;
  color: var(--black);
  margin-bottom: 12px;
  line-height: 1.4;
}
.feature-item p {
  font-size: 15px;
  color: var(--text-light);
  line-height: 1.8;
}

/* ===== Insight Cards ===== */
.insight-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
}
.insight-card {
  padding: 48px 36px;
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  transition: background .3s;
}
.insight-card:nth-child(3n) { border-right: none; }
.insight-card:hover { background: var(--off-white); }
.insight-tag {
  font-size: 12px;
  color: var(--red);
  letter-spacing: 1px;
  font-weight: 500;
  margin-bottom: 16px;
  text-transform: uppercase;
}
.insight-card h3 {
  font-size: 20px;
  font-weight: 500;
  color: var(--black);
  line-height: 1.4;
  margin-bottom: 12px;
}
.insight-card p {
  font-size: 14px;
  color: var(--text-light);
  line-height: 1.8;
}
.insight-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--red);
  font-weight: 500;
  margin-top: 20px;
  transition: gap .2s;
}
.insight-link:hover { gap: 10px; }

/* ===== Solution Detail ===== */
.solution-section {
  padding: 100px 0;
  border-bottom: 1px solid var(--border);
}
.solution-section:last-child { border-bottom: none; }
.solution-grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 80px;
}
.solution-sidebar h3 {
  font-size: 28px;
  font-weight: 300;
  color: var(--black);
  line-height: 1.3;
  margin-bottom: 16px;
}
.solution-sidebar h3 strong { font-weight: 600; }
.solution-sidebar p {
  font-size: 15px;
  color: var(--text-light);
  line-height: 1.8;
}
.solution-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
}
.solution-list-item {
  padding: 28px 24px;
  border-bottom: 1px solid var(--border);
  border-right: 1px solid var(--border);
  transition: background .2s;
}
.solution-list-item:nth-child(2n) { border-right: none; }
.solution-list-item:hover { background: var(--off-white); }
.solution-list-item h4 {
  font-size: 15px;
  font-weight: 500;
  color: var(--black);
  margin-bottom: 4px;
}
.solution-list-item p {
  font-size: 13px;
  color: var(--text-muted);
}

/* ===== Case Table ===== */
.case-filter {
  display: flex;
  gap: 24px;
  margin-bottom: 48px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}
.case-filter a {
  font-size: 14px;
  color: var(--text-muted);
  font-weight: 400;
  padding: 4px 0;
  transition: color .2s;
}
.case-filter a:hover, .case-filter a.active {
  color: var(--black);
  font-weight: 500;
}
.case-list { margin-top: 0; }
.case-item {
  display: grid;
  grid-template-columns: 60px 180px 1fr;
  gap: 0;
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
  align-items: center;
  transition: background .2s;
}
.case-item:hover { background: var(--off-white); margin: 0 -24px; padding: 20px 24px; }
.case-num { font-size: 13px; color: var(--text-muted); }
.case-client { font-size: 15px; font-weight: 500; color: var(--black); }
.case-project { font-size: 14px; color: var(--text-light); }
.case-more {
  text-align: center;
  padding: 40px 0;
  color: var(--text-muted);
  font-size: 14px;
}

/* ===== Contact ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
}
.contact-info h3 {
  font-size: 28px;
  font-weight: 300;
  color: var(--black);
  margin-bottom: 24px;
}
.contact-info p {
  font-size: 15px;
  color: var(--text-light);
  line-height: 1.9;
  margin-bottom: 32px;
}
.contact-item {
  margin-bottom: 20px;
}
.contact-item h5 {
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 4px;
  font-weight: 400;
}
.contact-item p {
  font-size: 15px;
  color: var(--text);
  margin: 0;
}
.contact-form { margin-top: 0; }
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 16px;
}
.form-group { margin-bottom: 16px; }
.form-group label {
  display: block;
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 0.5px;
  margin-bottom: 6px;
  font-weight: 500;
  text-transform: uppercase;
}
.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 10px 0;
  border: none;
  border-bottom: 1px solid var(--border);
  font-size: 15px;
  color: var(--text);
  font-family: var(--sans);
  background: transparent;
  transition: border-color .2s;
  outline: none;
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-bottom-color: var(--black);
}
.form-group textarea { resize:vertical; min-height:80px; }
.form-submit {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 32px;
  background: var(--black);
  color: var(--white);
  border: none;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background .2s;
  font-family: var(--sans);
}
.form-submit:hover { background: var(--red); }

/* ===== Footer ===== */
.footer {
  background: var(--black);
  color: rgba(255,255,255,.5);
  padding: 64px 0 32px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}
.footer-logo { margin-bottom: 16px; }
.footer-logo img { height: 24px; opacity: .6; }
.footer-brand p {
  font-size: 13px;
  line-height: 1.8;
  max-width: 280px;
}
.footer-col h6 {
  font-size: 11px;
  color: rgba(255,255,255,.4);
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 16px;
  font-weight: 500;
}
.footer-col a {
  display: block;
  font-size: 13px;
  padding: 3px 0;
  color: rgba(255,255,255,.5);
  transition: color .2s;
}
.footer-col a:hover { color: var(--white); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: rgba(255,255,255,.3);
}

/* ===== Utilities ===== */
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mt-48 { margin-top: 48px; }
.mt-64 { margin-top: 64px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.mb-48 { margin-bottom: 48px; }
.text-red { color: var(--red); }
.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 500;
  color: var(--red);
  transition: gap .2s;
}
.link-arrow:hover { gap: 10px; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .hero h1 { font-size: 42px; }
  .stat-row { grid-template-columns: repeat(2, 1fr); }
  .stat-item:nth-child(2) { border-right: none; }
  .stat-item:nth-child(1), .stat-item:nth-child(2) { border-bottom: 1px solid var(--border); }
  .insight-grid { grid-template-columns: repeat(2, 1fr); }
  .insight-card:nth-child(3n) { border-right: 1px solid var(--border); }
  .insight-card:nth-child(2n) { border-right: none; }
  .solution-grid { grid-template-columns: 1fr; gap: 40px; }
  .contact-grid { grid-template-columns: 1fr; gap: 48px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .container { padding: 0 24px; }
  .nav-links { display: none; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background: var(--white);
    padding: 24px;
    gap: 16px;
    border-bottom: 1px solid var(--border);
  }
  .nav-mobile-toggle { display: block; }
  .hero { min-height: 70vh; padding-bottom: 48px; }
  .hero h1 { font-size: 32px; }
  .hero-desc { font-size: 15px; }
  .page-header h1 { font-size: 32px; }
  .section { padding: 80px 0; }
  .section-title { font-size: 28px; }
  .stat-row { grid-template-columns: 1fr; }
  .stat-item { border-right: none !important; border-bottom: 1px solid var(--border); }
  .stat-item:last-child { border-bottom: none; }
  .feature-grid { grid-template-columns: 1fr; }
  .feature-item { border-right: none !important; }
  .insight-grid { grid-template-columns: 1fr; }
  .insight-card { border-right: none !important; }
  .solution-list { grid-template-columns: 1fr; }
  .solution-list-item { border-right: none !important; }
  .case-filter { flex-wrap: wrap; gap: 16px; }
  .case-item { grid-template-columns: 40px 1fr; }
  .case-client { grid-column: 2; }
  .case-project { grid-column: 2 / -1; }
  .form-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .footer-bottom { flex-direction: column; gap: 6px; }
}