@font-face {
  font-family: 'D-DIN';
  src: url('../fonts/D-DIN.otf') format('opentype');
  font-weight: 400;
  font-display: swap;
}
@font-face {
  font-family: 'D-DIN';
  src: url('../fonts/D-DIN-Bold.otf') format('opentype');
  font-weight: 700;
  font-display: swap;
}

/* ===== Solution pages ===== */

/* --- Banner (taller than product pages) --- */
.solution-banner {
  margin-top: var(--header-height, 72px);
  position: relative;
  overflow: hidden;
  height: 580px;
}
.solution-banner-bg {
  width: 100%; height: 100%; display: block; object-fit: cover;
  position: absolute; top: 0; left: 0;
}
.solution-banner-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(90deg, rgba(0,0,0,0.65) 0%, rgba(0,0,0,0.3) 50%, transparent 100%);
}
.solution-banner-text {
  position: absolute; top: 50%; left: 0; right: 0;
  transform: translateY(-50%);
  color: #fff;
}
.solution-banner-text h1 {
  font-size: 48px; font-weight: 700; margin-bottom: 16px; letter-spacing: 2px;
}
.solution-banner-text p {
  font-size: 18px; color: rgba(255,255,255,0.8); max-width: 600px; line-height: 1.7;
}

/* --- Section padding: generous vertical rhythm --- */
.pain-points-section,
.system-advantages,
.sc-section,
.system-case-highlight,
.system-faq {
  padding: 240px 0;
}

/* Alternate backgrounds */
.pain-points-section { background: #fff; }
.system-advantages { background: var(--color-sand); }
.sc-section { background: #fff; }
.system-case-highlight { background: var(--color-sand); }
.system-faq { background: #fff; }

/* --- Font consistency: all section titles use same size --- */
.sc-left .section-title {
  font-size: var(--font-size-h1);
}
.pain-points-section.why-section .why-title {
  font-size: var(--font-size-h1);
  font-weight: 500;
}

/* --- Pain Points: 4-item stagger --- */
.pain-points-section.why-section .why-item:nth-child(1) .why-body { padding-bottom: 200px; }
.pain-points-section.why-section .why-item:nth-child(2) .why-body { padding-bottom: 80px; }
.pain-points-section.why-section .why-item:nth-child(3) .why-body { padding-bottom: 260px; }
.pain-points-section.why-section .why-item:nth-child(4) .why-body { padding-bottom: 40px; }
.pain-points-section.why-section .why-title { margin-bottom: 64px; }
.pain-points-section.why-section .why-heading { font-size: 22px; margin-bottom: 20px; }
.pain-points-section.why-section .why-desc { font-size: 14px; }

/* --- System Advantages Grid --- */
.system-advantages-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.system-adv-card {
  background: #fff; padding: 80px 24px;
  border: 1px solid var(--color-border);
  transition: border-color 0.3s;
}
.system-adv-card:hover { border-color: var(--color-text-1); }
.system-adv-card-top { display: flex; align-items: center; gap: 14px; margin-bottom: 16px; }
.system-adv-card-title { font-size: 18px; font-weight: 500; color: var(--color-text-1); }
.system-adv-card-lottie {
  width: 48px; height: 48px; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
}
.system-adv-card-desc { font-size: 14px; line-height: 1.7; color: var(--color-text-2); }

/* --- Scenario Tabs --- */
.sc-wrap {
  display: grid;
  grid-template-columns: 1fr 1.6fr;
  gap: 60px;
  align-items: start;
}
.sc-left { display: flex; flex-direction: column; gap: 40px; padding-top: 10px; }
.sc-left .section-heading { margin-bottom: 0; }
.sc-left .section-title { text-align: left; }
.sc-tabs { display: flex; flex-direction: column; gap: 0; }
.sc-tab-item {
  display: flex; align-items: center; gap: 16px;
  padding: 20px 0; cursor: pointer;
  border-bottom: 1px solid var(--color-border);
  transition: all 0.3s ease;
}
.sc-tab-item:first-child { border-top: 1px solid var(--color-border); }
.sc-tab-num {
  font-family: 'D-DIN', monospace; font-size: 14px; font-weight: 700;
  color: var(--color-text-4); transition: color 0.3s ease; min-width: 28px;
}
.sc-tab-title {
  font-size: 16px; color: var(--color-text-3); font-weight: 400;
  transition: all 0.3s ease;
}
.sc-tab-item.active .sc-tab-num { color: var(--color-primary); }
.sc-tab-item.active .sc-tab-title {
  color: var(--color-text-1); font-weight: 600; font-size: 18px;
}
.sc-tab-item:hover:not(.active) .sc-tab-title { color: var(--color-text-2); }

.sc-nav { display: flex; align-items: center; gap: 16px; }
.sc-arrow {
  width: 40px; height: 40px;
  border: 1.5px solid var(--color-border); background: #fff;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer; transition: all 0.25s ease; color: var(--color-text-2);
}
.sc-arrow:hover { border-color: var(--color-text-1); color: var(--color-text-1); }
.sc-progress {
  flex: 1; height: 2px; background: var(--color-border); overflow: hidden;
}
.sc-progress-bar {
  height: 100%; background: var(--color-primary);
  transition: width 0.4s ease; width: 33.33%;
}

.sc-right { display: flex; flex-direction: column; gap: 24px; }
.sc-image { overflow: hidden; aspect-ratio: 16 / 10; }
.sc-image img { width: 100%; height: 100%; object-fit: cover; display: block; }

.sc-panel { display: none; animation: scFadeIn 0.4s ease; }
.sc-panel.active { display: block; }
@keyframes scFadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}
.sc-panel-desc {
  font-size: 15px; color: var(--color-text-2); line-height: 1.8; margin: 0 0 20px;
}
.sc-panel-tags { display: flex; flex-wrap: wrap; gap: 10px; }
.sc-panel-tag {
  background: #fff; border: 1px solid var(--color-border);
  padding: 8px 18px;
  font-size: 13px; color: var(--color-text-2); font-weight: 500;
  transition: all 0.25s ease;
}
.sc-panel-tag:hover {
  border-color: var(--color-primary); color: var(--color-primary);
  background: rgba(3,99,233,0.04);
}

/* --- Case Carousel (reuses homepage .cases-card styles) --- */
.sol-cases-row {
  display: flex;
  gap: 20px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
  padding: 0 var(--page-padding) 8px;
}
.sol-cases-row::-webkit-scrollbar { display: none; }
.sol-cases-row .cases-card {
  flex: 0 0 calc((100vw - 2 * var(--page-padding) - 2 * 20px) / 3);
  scroll-snap-align: start;
}
.system-case-highlight .cases-nav {
  padding-top: 40px;
}

/* --- FAQ --- */
.system-faq .faq-list {
  display: flex; flex-direction: column; gap: 12px;
}
.system-faq .faq-item {
  background: #fff; border: 1px solid var(--color-border);
  overflow: hidden; transition: all 0.3s ease;
}
.system-faq .faq-item:hover { border-color: var(--color-text-1); }
.system-faq .faq-q {
  padding: 20px 24px; font-size: 16px; font-weight: 500; color: var(--color-text-1);
  display: flex; justify-content: space-between; align-items: center; cursor: pointer;
}
.system-faq .faq-q::after {
  content: "+"; font-size: 24px; font-weight: 300; color: var(--color-text-3);
  transition: transform 0.3s ease; line-height: 1;
}
.system-faq .faq-item.open .faq-q::after { transform: rotate(45deg); }
.system-faq .faq-a {
  max-height: 0; overflow: hidden; transition: max-height 0.4s ease, padding 0.4s ease;
  padding: 0 24px; font-size: 14px; color: var(--color-text-2); line-height: 1.8;
}
.system-faq .faq-item.open .faq-a { max-height: 400px; padding: 0 24px 20px; }

/* --- Responsive --- */
@media (max-width: 1024px) {
  .solution-banner { height: 420px; }
  .solution-banner-text h1 { font-size: 36px; }
  .pain-points-section,
  .system-advantages,
  .sc-section,
  .system-case-highlight,
  .system-faq { padding: 80px 0; }
  .system-advantages-grid { grid-template-columns: 1fr; }
  .system-adv-card { padding: 48px 24px; }
  .sc-wrap { grid-template-columns: 280px 1fr; gap: 40px; }
  .sc-left .section-title { font-size: 28px; }
  .pain-points-section.why-section .why-title { font-size: 28px; }
  .pain-points-section.why-section .why-heading { font-size: 20px; }
  .pain-points-section.why-section .why-num { font-size: 48px; }
  .sol-cases-row .cases-card {
    flex: 0 0 calc((100vw - 2 * var(--page-padding) - 20px) / 2);
  }
}
@media (max-width: 767px) {
  .solution-banner { height: 340px; }
  .solution-banner-text h1 { font-size: 28px; }
  .pain-points-section,
  .system-advantages,
  .sc-section,
  .system-case-highlight,
  .system-faq { padding: 60px 0; }
  .pain-points-section.why-section .why-list { flex-direction: column; }
  .pain-points-section.why-section .why-item {
    border-bottom: 2px solid var(--color-text-1);
    padding-bottom: 40px; margin-bottom: 40px;
  }
  .pain-points-section.why-section .why-item:last-child {
    border-bottom: 4px solid var(--color-text-1); margin-bottom: 0;
  }
  .pain-points-section.why-section .why-item .why-body { padding-bottom: 0; }
  .pain-points-section.why-section .why-title { font-size: 28px; margin-bottom: 48px; }
  .pain-points-section.why-section .why-num { font-size: 40px; }
  .sc-wrap { grid-template-columns: 1fr; gap: 24px; }
  .sc-left { gap: 24px; }
  .sc-tabs { flex-direction: row; overflow-x: auto; gap: 0; }
  .sc-tab-item { flex-shrink: 0; border-bottom: 2px solid transparent; border-top: none; padding: 12px 16px; }
  .sc-tab-item:first-child { border-top: none; }
  .sc-tab-item.active { border-bottom-color: var(--color-primary); }
  .system-adv-card { padding: 32px 20px; }
  .system-adv-card-title { font-size: 16px; }
  .system-faq .faq-q { padding: 16px 20px; }
  .sol-cases-row .cases-card {
    flex: 0 0 calc(100vw - 2 * var(--page-padding) - 20px);
  }
}