/* ==========================================================================
   About Page Styles - Engineered Mineral / 岩层工程感
   ========================================================================== */

.hu-about {
  width: 100%;
  margin: 0;
  padding: 0;
}

.hu-container {
  max-width: var(--max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* Eyebrows & Typography */
.hu-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
  color: var(--steel);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.hu-eyebrow.light {
  color: #94A3B8;
}
.hu-heading-area {
  margin-bottom: 48px;
}
.hu-heading-area h2 {
  font-size: clamp(28px, 4vw, 38px);
  line-height: 1.15;
  color: var(--basalt);
  margin: 0 0 16px;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.hu-heading-area.light h2 {
  color: #FFFFFF;
}
.hu-lead {
  font-size: 18px;
  line-height: 1.6;
  color: var(--slate);
  max-width: 780px;
  margin: 0;
}
.hu-lead.light {
  color: var(--mist);
}

/* Gray Blocks for Images (图片用一个灰块表示) */
.hu-gray-block {
  background: #D8DFE2;
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: flex-end;
  border: 1px solid var(--line);
}
.hu-gray-block.dark-mode {
  background: #1B2F3D;
  border-color: rgba(255,255,255,0.08);
}
.hu-gray-caption {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 10px 14px;
  background: rgba(16, 42, 58, 0.85);
  color: #FFFFFF;
  margin: 12px;
  border-left: 2px solid var(--orange);
}

/* Sections */
.hu-section {
  padding: 80px 0;
}
.hu-section.white {
  background: var(--white);
  border-bottom: 1px solid var(--line);
}
.hu-section.mineral {
  background: var(--mineral);
  border-bottom: 1px solid var(--line);
}
.hu-section.dark {
  background: var(--navy);
  color: var(--mist);
}

/* Hero Section */
.hu-hero {
  background: var(--navy);
  color: #FFFFFF;
  padding: 80px 0 60px;
  position: relative;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.hu-hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
}
.hu-hero h1 {
  font-size: clamp(34px, 4.5vw, 50px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  margin: 0 0 24px;
  font-weight: 700;
}
.hu-hero h1 span {
  color: var(--orange);
}
.hu-hero-copy {
  font-size: 18px;
  line-height: 1.6;
  color: var(--mist);
  margin-bottom: 36px;
  max-width: 580px;
}
.hu-hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  padding-top: 28px;
  border-top: 1px solid rgba(255,255,255,0.12);
}
.hu-hero-stat strong {
  display: block;
  font-family: var(--font-sans);
  font-size: 26px;
  color: #FFFFFF;
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 6px;
}
.hu-hero-stat span {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--steel);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.hu-hero-image-block {
  height: 420px;
}

/* Trust Bar */
.hu-trustbar {
  background: var(--navy-deep);
  color: var(--steel);
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 16px 0;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}
.hu-trustbar-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}
.hu-trustbar-title {
  color: #FFFFFF;
  font-weight: 600;
  letter-spacing: 0.08em;
}
.hu-trust-items {
  display: flex;
  gap: 28px;
  flex-wrap: wrap;
}
.hu-trust-item {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--mist);
}
.hu-trust-item::before {
  content: "■";
  color: var(--orange);
  font-size: 8px;
}

/* 3-Column Cards (Who We Are) */
.hu-cards-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.hu-card {
  background: var(--mineral);
  padding: 32px 28px;
  border-left: 3px solid var(--navy);
  border-top: 1px solid var(--line);
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.hu-card-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--orange);
  font-weight: 600;
  display: block;
  margin-bottom: 12px;
}
.hu-card h3 {
  font-size: 19px;
  color: var(--basalt);
  margin: 0 0 12px;
  font-weight: 600;
  line-height: 1.3;
}
.hu-card p {
  color: var(--slate);
  font-size: 15px;
  line-height: 1.6;
  margin: 0;
}

/* Manufacturing Capability Grid */
.hu-cap-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 48px;
  align-items: center;
}
.hu-cap-image-block {
  height: 380px;
}
.hu-stats-4 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-top: 32px;
}
.hu-stat-box {
  background: rgba(255,255,255,0.03);
  border: 1px solid rgba(255,255,255,0.08);
  padding: 20px;
}
.hu-stat-box strong {
  display: block;
  font-size: 28px;
  color: #FFFFFF;
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 6px;
}
.hu-stat-box span {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--steel);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}
.hu-fineprint {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--steel);
  margin-top: 24px;
  line-height: 1.5;
}

/* Product Families */
.hu-product-rows {
  display: grid;
  gap: 16px;
  margin-bottom: 36px;
}
.hu-prod-row {
  display: grid;
  grid-template-columns: 80px 1.2fr 2fr;
  gap: 24px;
  padding: 24px;
  background: var(--mineral);
  border: 1px solid var(--line);
  align-items: baseline;
}
.hu-prod-num {
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--orange);
  font-weight: 600;
}
.hu-prod-title h3 {
  font-size: 18px;
  color: var(--basalt);
  margin: 0;
  font-weight: 600;
}
.hu-prod-desc p {
  font-size: 14px;
  color: var(--slate);
  margin: 0;
}

/* Application 4-Grid */
.hu-app-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.hu-app-card {
  position: relative;
  height: 240px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
}
.hu-app-caption {
  position: relative;
  z-index: 2;
  padding: 16px 20px;
  background: rgba(10, 29, 40, 0.9);
  border-top: 1px solid rgba(255,255,255,0.1);
}
.hu-app-caption span {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--orange);
  text-transform: uppercase;
  display: block;
  margin-bottom: 4px;
}
.hu-app-caption h3 {
  font-size: 17px;
  color: #FFFFFF;
  margin: 0;
  font-weight: 600;
}

/* 6-Step Workflow */
.hu-steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.hu-step-card {
  background: var(--white);
  border: 1px solid var(--line);
  padding: 28px 24px;
  position: relative;
}
.hu-step-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--orange);
  font-weight: 600;
  display: block;
  margin-bottom: 12px;
}
.hu-step-card h3 {
  font-size: 17px;
  color: var(--basalt);
  margin: 0 0 8px;
  font-weight: 600;
}
.hu-step-card p {
  font-size: 14px;
  color: var(--slate);
  margin: 0;
}

/* Documentation Layout */
.hu-doc-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}
.hu-doc-panel {
  background: var(--mineral);
  border: 1px solid var(--line);
}
.hu-doc-panel-head {
  display: flex;
  justify-content: space-between;
  padding: 14px 20px;
  background: var(--navy);
  color: #FFFFFF;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.hu-doc-list {
  padding: 16px 20px;
}
.hu-doc-row {
  display: grid;
  grid-template-columns: 50px 1fr 90px;
  gap: 16px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
  align-items: center;
}
.hu-doc-row:last-child {
  border-bottom: none;
}
.hu-file-tag {
  font-family: var(--font-mono);
  font-size: 10px;
  padding: 3px 6px;
  background: var(--mist);
  color: var(--slate);
  text-align: center;
  font-weight: 600;
}
.hu-doc-status {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--green);
  text-align: right;
  font-weight: 500;
}

/* Scope Split (Included vs Boundaries) */
.hu-scope-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}
.hu-scope-card {
  padding: 32px;
  border: 1px solid var(--line);
  background: var(--mineral);
}
.hu-scope-card.included {
  border-top: 3px solid var(--green);
}
.hu-scope-card.boundary {
  border-top: 3px solid var(--steel);
}
.hu-scope-card h3 {
  font-size: 18px;
  margin: 0 0 16px;
  font-weight: 600;
}
.hu-scope-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.hu-scope-list li {
  padding: 8px 0 8px 24px;
  position: relative;
  font-size: 14px;
  color: var(--slate);
  border-bottom: 1px solid var(--line);
}
.hu-scope-list li:last-child {
  border-bottom: none;
}
.hu-scope-card.included li::before {
  content: "✓";
  color: var(--green);
  position: absolute;
  left: 0;
  font-weight: bold;
}
.hu-scope-card.boundary li::before {
  content: "—";
  color: var(--steel);
  position: absolute;
  left: 0;
  font-weight: bold;
}

/* Contact Strip */
.hu-contact-box {
  background: var(--navy);
  color: #FFFFFF;
  padding: 48px;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
}
.hu-contact-points {
  display: grid;
  gap: 16px;
}
.hu-c-point {
  display: flex;
  gap: 16px;
  align-items: baseline;
}
.hu-c-point span:first-child {
  font-family: var(--font-mono);
  color: var(--orange);
  font-weight: 600;
  font-size: 13px;
}
.hu-c-point span:last-child {
  font-size: 14px;
  color: var(--mist);
}

/* Responsive */
@media (max-width: 900px) {
  .hu-hero-grid,
  .hu-cap-grid,
  .hu-doc-layout,
  .hu-contact-box {
    grid-template-columns: 1fr;
  }
  .hu-cards-3,
  .hu-steps-grid {
    grid-template-columns: 1fr;
  }
  .hu-app-grid,
  .hu-scope-grid {
    grid-template-columns: 1fr;
  }
  .hu-prod-row {
    grid-template-columns: 1fr;
    gap: 8px;
  }
  .hu-hero-stats {
    grid-template-columns: 1fr;
  }
  .hu-hero-image-block {
    height: 280px;
  }
}

/* Images in the placeholder slots */
.hu-image img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.hu-app-card.hu-image img {
  position: absolute;
  inset: 0;
}

/* Tianjin export team */
.hu-team-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 48px;
  align-items: center;
}
.hu-team-image {
  background: var(--white);
  border: 1px solid var(--line);
}
.hu-team-facts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin: 28px 0 0;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}
.hu-team-fact strong {
  display: block;
  margin-bottom: 4px;
  color: var(--navy);
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 600;
}
.hu-team-fact span {
  color: var(--steel);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

@media (max-width: 1000px) {
  .hu-team-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
}
@media (max-width: 640px) {
  .hu-team-facts {
    grid-template-columns: 1fr;
    gap: 14px;
  }
}

/* The factory slot shows the full 5:4 frame of its photo (media 17, 1000x800) */
.hu-cap-image-block.hu-image {
  height: auto;
  aspect-ratio: 5 / 4;
}