:root {
  --blue: #1f6fd6;
  --blue-dark: #1557ad;
  --ink: #2a2f36;
  --muted: #6b7280;
  --line: #e6e9ef;
  --bg: #ffffff;
  --band: #f5f7fb;
  --max: 1180px;
  --header-h: 72px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: "Noto Sans SC", sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: #fff;
  border-bottom: 1px solid var(--line);
  box-shadow: 0 1px 0 rgba(0,0,0,0.02);
}
.header-inner {
  max-width: var(--max);
  margin: 0 auto;
  min-height: var(--header-h);
  padding: 0 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  min-width: 0;
  flex-shrink: 1;
}
.logo-mark {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 8px;
  background: linear-gradient(145deg, var(--blue), #3d8ef0);
  color: #fff;
  font-weight: 900;
  font-size: 0.95rem;
  letter-spacing: 0.04em;
}
.logo-text {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 14rem;
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.15rem;
  margin-left: auto;
  font-size: 0.95rem;
  color: #4b5563;
}
.nav a:hover,
.nav a.active { color: var(--blue); }

.search {
  display: flex;
  align-items: stretch;
  flex-shrink: 0;
  border: 1px solid #d7dde8;
  border-radius: 4px;
  overflow: hidden;
  background: #fff;
}
.search input {
  width: 150px;
  border: 0;
  outline: 0;
  padding: 0.45rem 0.7rem;
  font: inherit;
  font-size: 0.88rem;
}
.search button {
  border: 0;
  background: var(--blue);
  color: #fff;
  padding: 0 0.85rem;
  font: inherit;
  font-size: 0.88rem;
  cursor: pointer;
}
.search button:hover { background: var(--blue-dark); }

.menu-btn {
  display: none;
  border: 1px solid var(--line);
  background: #fff;
  width: 40px;
  height: 40px;
  border-radius: 6px;
  font-size: 1.2rem;
  cursor: pointer;
}

/* Hero — diagonal 3-pane carousel */
.hero {
  position: relative;
  height: min(72vh, 620px);
  min-height: 420px;
  overflow: hidden;
  background: #0f1724;
}
.slides { height: 100%; }
.slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.7s ease;
}
.slide.is-active {
  opacity: 1;
  pointer-events: auto;
}
.slide-photo {
  background: #0a1628;
}
.slide-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  transform: scale(1.02);
  transition: transform 6s ease;
}
.slide.is-active .slide-img { transform: scale(1.06); }

.pane {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  transform: scale(1.02);
  transition: transform 6s ease;
}
.slide.is-active .pane { transform: scale(1.08); }

.slide[data-tone="a"] .p1 {
  background-image:
    linear-gradient(120deg, rgba(10,20,40,0.35), rgba(10,20,40,0.1)),
    linear-gradient(135deg, #1a3a66, #2f6fb4 45%, #6aa8e8);
  clip-path: polygon(0 0, 42% 0, 28% 100%, 0 100%);
}
.slide[data-tone="a"] .p2 {
  background-image:
    linear-gradient(180deg, rgba(0,0,0,0.25), rgba(0,0,0,0.35)),
    linear-gradient(160deg, #274f7d, #1d6bb8 40%, #3f8fd8);
  clip-path: polygon(40% 0, 72% 0, 58% 100%, 26% 100%);
}
.slide[data-tone="a"] .p3 {
  background-image:
    linear-gradient(210deg, rgba(0,0,0,0.15), rgba(0,0,0,0.4)),
    linear-gradient(200deg, #3b6ea8, #5b9de0);
  clip-path: polygon(70% 0, 100% 0, 100% 100%, 56% 100%);
}

.slide[data-tone="b"] .p1 {
  background-image: linear-gradient(135deg, #16324f, #2a6f9c 50%, #57a0cf);
  clip-path: polygon(0 0, 42% 0, 28% 100%, 0 100%);
}
.slide[data-tone="b"] .p2 {
  background-image: linear-gradient(160deg, #0f3d57, #1f7aad 40%, #49b0d8);
  clip-path: polygon(40% 0, 72% 0, 58% 100%, 26% 100%);
}
.slide[data-tone="b"] .p3 {
  background-image: linear-gradient(200deg, #1b4f73, #3d8fbf);
  clip-path: polygon(70% 0, 100% 0, 100% 100%, 56% 100%);
}

.slide-copy {
  position: absolute;
  inset: 0;
  z-index: 2;
  display: grid;
  place-content: center;
  text-align: center;
  color: #fff;
  padding: 1.5rem;
  text-shadow: 0 2px 16px rgba(0,0,0,0.35);
  animation: rise 0.8s ease both;
}
.slide.is-active .slide-copy { animation: rise 0.8s ease both; }
@keyframes rise {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}
.slide-copy h1 {
  margin: 0 0 0.7rem;
  font-size: clamp(1.8rem, 4.2vw, 2.8rem);
  font-weight: 900;
  letter-spacing: 0.04em;
}
.slide-copy p {
  margin: 0;
  font-size: clamp(0.95rem, 1.8vw, 1.15rem);
  opacity: 0.95;
}

.hero-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 3;
  width: 44px;
  height: 56px;
  border: 0;
  border-radius: 4px;
  background: rgba(80, 90, 105, 0.45);
  color: #fff;
  font-size: 2rem;
  line-height: 1;
  cursor: pointer;
  backdrop-filter: blur(2px);
}
.hero-arrow:hover { background: rgba(60, 70, 85, 0.65); }
.hero-arrow.prev { left: 12px; }
.hero-arrow.next { right: 12px; }

.dots {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 18px;
  z-index: 3;
  display: flex;
  justify-content: center;
  gap: 8px;
}
.dots button {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: 0;
  background: rgba(255,255,255,0.45);
  cursor: pointer;
  padding: 0;
}
.dots button.is-on { background: #fff; }

.section {
  max-width: var(--max);
  margin: 0 auto;
  padding: 3.5rem 1.25rem;
}
.section.band {
  max-width: none;
  padding-left: max(1.25rem, calc((100% - var(--max)) / 2));
  padding-right: max(1.25rem, calc((100% - var(--max)) / 2));
  background: var(--band);
}
.section h2 {
  margin: 0 0 0.6rem;
  text-align: center;
  font-size: 1.75rem;
  font-weight: 900;
}
.section-lead {
  margin: 0 auto 2rem;
  max-width: 40rem;
  text-align: center;
  color: var(--muted);
}

.feature-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.25rem;
}
.feature-list.three { grid-template-columns: repeat(3, 1fr); }
.feature-list li {
  padding: 1.25rem 0;
  border-top: 1px solid var(--line);
}
.feature-list strong {
  display: block;
  margin-bottom: 0.35rem;
  font-size: 1.08rem;
}
.feature-list span { color: var(--muted); font-size: 0.95rem; }

.sol-block {
  padding: 2rem 0;
  border-top: 1px solid var(--line);
}
.sol-block:first-of-type { border-top: 0; padding-top: 0.5rem; }
.sol-head h3 {
  margin: 0 0 0.25rem;
  font-size: 1.35rem;
  color: var(--blue);
}
.sol-head p {
  margin: 0 0 0.9rem;
  color: var(--muted);
  font-size: 0.95rem;
}
.sol-intro {
  margin: 0 0 1.25rem;
  color: #3f4652;
  font-size: 0.98rem;
  max-width: 52rem;
}
.sol-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 1.5rem 2rem;
}
.sol-grid h4 {
  margin: 0 0 0.55rem;
  font-size: 1rem;
}
.sol-grid ul {
  margin: 0;
  padding-left: 1.1rem;
  color: var(--muted);
  font-size: 0.92rem;
}
.sol-grid li { margin: 0.35rem 0; }

.case-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}
.case-card {
  padding: 1.25rem 0;
  border-top: 2px solid var(--blue);
}
.case-tag {
  display: inline-block;
  margin-bottom: 0.55rem;
  color: var(--blue);
  font-size: 0.82rem;
  font-weight: 700;
}
.case-card h3 {
  margin: 0 0 0.55rem;
  font-size: 1.08rem;
}
.case-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.contact-block {
  max-width: 28rem;
  margin: 0 auto;
  padding: 1.5rem 0 0;
  border-top: 1px solid var(--line);
}
.contact-block p {
  display: grid;
  grid-template-columns: 5.5rem 1fr;
  gap: 0.75rem;
  margin: 0.7rem 0;
  font-size: 1.02rem;
}
.contact-block span { color: var(--muted); }
.contact-block a { color: var(--blue); font-weight: 700; }

.site-footer {
  border-top: 1px solid var(--line);
  padding: 1.5rem 1rem 2rem;
  text-align: center;
  color: var(--muted);
  font-size: 0.88rem;
  background: #fff;
}
.site-footer p { margin: 0.25rem 0; }
.site-footer a { color: var(--blue); }

@media (max-width: 980px) {
  .logo-text { max-width: 8.5rem; font-size: 0.82rem; }
  .nav { display: none; }
  .nav.open {
    display: flex;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 0.5rem 0;
  }
  .nav.open a { padding: 0.85rem 1.25rem; }
  .menu-btn { display: inline-flex; align-items: center; justify-content: center; margin-left: auto; }
  .search { display: none; }
  .feature-list.three { grid-template-columns: 1fr; }
  .sol-grid { grid-template-columns: 1fr; }
  .case-grid { grid-template-columns: 1fr; }
  .hero { min-height: 360px; height: 56vh; }
}