/* 2026-10-15 炭黑纸感、柔光与克制暗纹 */
:root {
  color-scheme: dark;
  --paper: #171717;
  --ink: #f6f6f6;
  --muted: #b6b7bb;
  --line: rgba(255, 255, 255, 0.13);
  --orange-text: #ff633c;
  --dark-muted: #b6b7bb;
}

body {
  background: #171717;
}

main > section,
.site-footer {
  position: relative;
  isolation: isolate;
}

/* 纹理位于内容下方，不覆盖人像、文字与二维码。 */
main > section::before,
.site-footer::before {
  content: "";
  position: absolute;
  z-index: -1;
  inset: 0;
  background: url("assets/charcoal-grain.svg") repeat;
  background-size: 192px 192px;
  mix-blend-mode: soft-light;
  opacity: 0.48;
  pointer-events: none;
}

.site-header {
  background: linear-gradient(110deg, rgba(29, 29, 31, 0.95), rgba(20, 20, 22, 0.94));
  border-bottom-color: rgba(255, 255, 255, 0.09);
}

.hero {
  background:
    radial-gradient(ellipse at 76% 28%, rgba(226, 223, 213, 0.055), transparent 54%),
    linear-gradient(118deg, #151516 9%, #1c1d1f 66%, #171719);
}

.hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  inset: 0;
  background:
    linear-gradient(116deg, transparent 51%, rgba(230, 225, 213, 0.027) 51.1%, transparent 78%),
    repeating-linear-gradient(116deg, transparent 0 178px, rgba(255, 255, 255, 0.025) 179px, transparent 180px 358px);
  -webkit-mask-image: linear-gradient(to right, transparent 18%, #000 70%);
  mask-image: linear-gradient(to right, transparent 18%, #000 70%);
  pointer-events: none;
}

#fit {
  background: linear-gradient(128deg, #18191a, #151617 72%);
}

#team {
  background:
    radial-gradient(ellipse at 85% 42%, rgba(222, 218, 205, 0.028), transparent 55%),
    linear-gradient(112deg, #18181a, #1b1c1e);
}

#method {
  background: linear-gradient(122deg, #141517, #1a1b1d 72%, #18181a);
}

.header-contact,
.button.primary {
  background: #f6f6f6;
  color: #171717;
}

.button.secondary {
  background: transparent;
  color: var(--ink);
}

.hero-topics li,
.fit-item,
.service-card,
.method-steps article,
.team-delivery,
.brand-wall-grid li {
  background: linear-gradient(132deg, rgba(255, 255, 255, 0.038), transparent 75%), #202123;
  border-color: rgba(255, 255, 255, 0.11);
}

.fit-item,
.service-card,
.team-delivery,
.method-steps article {
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.025), 0 12px 32px rgba(0, 0, 0, 0.07);
}

.section-paper {
  background:
    radial-gradient(ellipse at 12% 10%, rgba(255, 99, 60, 0.025), transparent 46%),
    linear-gradient(116deg, #1c1d1f, #18191b 68%, #1c1d1e);
  border-block: 1px solid rgba(255, 255, 255, 0.07);
}

.service-fit {
  background: linear-gradient(120deg, rgba(255, 255, 255, 0.018), transparent), rgba(8, 9, 11, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.045);
}

.founders-photo-wrap::before {
  inset: 4% -4% 5%;
  border-radius: 0;
  background: radial-gradient(ellipse closest-side at 50% 45%,
    rgba(255, 255, 255, 0.14) 0%,
    rgba(255, 255, 255, 0.09) 38%,
    rgba(255, 255, 255, 0.03) 70%,
    rgba(255, 255, 255, 0) 100%);
}

.credibility-strip {
  background: linear-gradient(105deg, #242527, #1e1f21 60%, #222325);
  border-block: 1px solid rgba(255, 255, 255, 0.09);
}

.insight-grid article {
  background: linear-gradient(132deg, rgba(255, 255, 255, 0.028), transparent), #202123;
  border: 1px solid rgba(255, 255, 255, 0.09);
}

.contact-section {
  background:
    radial-gradient(ellipse at 10% 90%, rgba(255, 99, 60, 0.024), transparent 46%),
    linear-gradient(120deg, #161719, #1b1c1e 64%, #151618);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.qr-card {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.035), transparent), rgba(255, 255, 255, 0.018);
  border-color: rgba(255, 255, 255, 0.12);
}

.site-footer {
  background: linear-gradient(120deg, #111214, #18191b 62%, #121315);
  border-top: 1px solid rgba(255, 255, 255, 0.065);
}

.fit-note,
.credit-note {
  background: linear-gradient(100deg, rgba(255, 99, 60, 0.055), rgba(255, 99, 60, 0.012));
  border-left-color: rgba(255, 99, 60, 0.65);
}

@media (hover: hover) and (pointer: fine) {
  .brand-wall-grid li:hover {
    background: linear-gradient(130deg, #2b2d30, #242628);
  }
}

/* 人物轮廓与炭黑背景保持柔和的分离 */
.founders-photo {
  filter: drop-shadow(0 0 11px rgba(255, 255, 255, 0.16));
}

@media (max-width: 720px) {
  .hero::after {
    opacity: 0.6;
  }
}