/* fde.unvessel.ai/zh — 结构参照 Palantir 主站：教义条 / 全屏首屏 /
   program 式方向卡 / 简报式栏目。基调黑白，唯一点缀色为朱红 #FF4C00，
   只做局部高对比（句号、编号、勾选、主按钮）。
   字号 18px 起，为 45–60 岁的读者与微信内置浏览器优化。 */

:root {
  --bg: #0f0f0f;
  --bg-soft: #161616;
  --card: #1a1a1a;
  --line: #2a2a2a;
  --text: #f2f2f2;
  --text-soft: #b0b0b0;
  --zhu: #FF4C00;          /* 朱红 */
  --zhu-press: #e04300;
}

*, *::before, *::after { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, "PingFang SC", "Noto Sans SC",
               "Microsoft YaHei", "Helvetica Neue", sans-serif;
  font-size: 1.125rem;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, p, ol, ul { margin: 0; }
a { color: inherit; }

:focus-visible { outline: 2px solid var(--text); outline-offset: 3px; }

.zhu { color: var(--zhu); } /* 朱红：只用于语义强调 */

/* ---------- 教义条 ---------- */

.motto {
  background: #000000;
  color: var(--text-soft);
  text-align: center;
  font-size: 0.85rem;
  letter-spacing: 0.35em;
  padding: 0.5rem 1rem 0.5rem calc(1rem + 0.35em);
  border-bottom: 1px solid var(--line);
}

/* ---------- 页头 ---------- */

.top {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(15, 15, 15, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.top__inner {
  max-width: 68rem;
  margin: 0 auto;
  padding: 0.8rem clamp(1rem, 4vw, 2rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.top__brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  white-space: nowrap;
}
.top__brand b { font-size: 1.05rem; }
.top__en { font-size: 0.7rem; letter-spacing: 0.08em; color: var(--text-soft); }
.top__nav { display: flex; gap: clamp(0.9rem, 2.5vw, 1.5rem); font-size: 0.95rem; }
.top__nav a { color: var(--text-soft); text-decoration: none; }
.top__nav a:hover { color: var(--text); }
.top__lang { color: var(--text); }
@media (max-width: 560px) {
  .top__nav a:not(.top__lang) { display: none; }
}

/* ---------- 首屏（大图/动画位） ---------- */

.hero {
  min-height: 88svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  position: relative;
  /* 动画/大图之后放这里；先以纯黑 + 轻微渐晕承载 */
  background:
    radial-gradient(ellipse 90% 70% at 50% 35%, #1c1c1c 0%, var(--bg) 70%);
}
.hero__inner {
  max-width: 68rem;
  margin: 0 auto;
  padding: clamp(3rem, 10vw, 5rem) clamp(1rem, 4vw, 2rem);
  width: 100%;
}
.hero__tag {
  display: inline-block;
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  color: var(--text-soft);
  border: 1px solid var(--line);
  border-radius: 99px;
  padding: 0.25rem 0.9rem;
  margin-bottom: 1.6rem;
}
.hero h1 {
  font-size: clamp(2.6rem, 9vw, 4.6rem);
  line-height: 1.22;
  font-weight: 700;
  letter-spacing: 0.01em;
  margin-bottom: 1.4rem;
}
.hero__sub {
  font-size: clamp(1.15rem, 2.6vw, 1.4rem);
  line-height: 1.7;
  color: var(--text);
  margin-bottom: 1.2rem;
  max-width: min(30rem, 100%);
}

/* 方法说明：比主张低一档，与其拉开层级 */
.hero__note {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-soft);
  max-width: min(30rem, 100%);
  padding-left: 0.9rem;
  border-left: 1px solid var(--line);
  margin-bottom: 2rem;
}

.btn {
  display: inline-block;
  background: #ffffff;
  color: #111111;
  text-decoration: none;
  font-size: 1.1rem;
  font-weight: 600;
  padding: 0.85rem 1.9rem;
  border-radius: 4px;
}
.btn:hover { background: #d9d9d9; }

.hero__scroll {
  position: absolute;
  bottom: 1.2rem;
  left: 0; right: 0;
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-soft);
  letter-spacing: 0.1em;
}

/* ---------- 栏目通用 ---------- */

main { max-width: 68rem; margin: 0 auto; padding: 0 clamp(1rem, 4vw, 2rem); }

.band { padding-top: clamp(4rem, 10vw, 6rem); }

.band__label {
  font-size: 0.9rem;
  letter-spacing: 0.25em;
  color: var(--text-soft);
  border-left: 3px solid var(--text-soft);
  padding-left: 0.7rem;
  margin-bottom: 1.8rem;
}

/* ---------- 服务方向（program 卡） ---------- */

.programs { display: grid; gap: 1rem; }
@media (min-width: 760px) { .programs { grid-template-columns: repeat(3, 1fr); } }

.program {
  background: var(--card);
  border: 1px solid var(--line);
  padding: 1.6rem 1.5rem 1.8rem;
}
.program__chip {
  display: inline-block;
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  color: var(--text-soft);
  border: 1px solid var(--line);
  border-radius: 99px;
  padding: 0.2rem 0.8rem;
  margin-bottom: 1.1rem;
}
.program h2 {
  font-size: clamp(1.4rem, 3.6vw, 1.65rem);
  line-height: 1.45;
  font-weight: 700;
  margin-bottom: 0.8rem;
}
.program p { font-size: 1rem; color: var(--text-soft); }

/* ---------- 合作三步 ---------- */

.steps {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 1rem;
}
@media (min-width: 760px) { .steps { grid-template-columns: repeat(3, 1fr); } }
.steps li {
  background: var(--card);
  border: 1px solid var(--line);
  padding: 1.4rem 1.5rem 1.6rem;
}
.steps__num {
  display: block;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-soft);
  letter-spacing: 0.1em;
  margin-bottom: 0.6rem;
}
.steps h3 { font-size: 1.2rem; margin-bottom: 0.4rem; }
.steps p { font-size: 1rem; color: var(--text-soft); }

.promise {
  margin-top: 1rem;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  padding: 1.5rem 1.6rem;
}
.promise h3 { font-size: 1.15rem; margin-bottom: 0.8rem; }
.promise ul { list-style: none; padding: 0; display: grid; gap: 0.5rem; }
@media (min-width: 760px) { .promise ul { grid-template-columns: 1fr 1fr; } }
.promise li { padding-left: 1.6em; position: relative; }
.promise li::before {
  content: "✓";
  position: absolute;
  left: 0.2em;
  color: var(--text-soft);
  font-weight: 700;
}
.promise li .zhu { font-weight: 600; }

/* ---------- 关于 ---------- */

.about { max-width: 46rem; display: grid; gap: 1rem; }
.about p { color: var(--text-soft); }
.about__rule {
  font-size: clamp(1.3rem, 3.6vw, 1.6rem);
  font-weight: 700;
  color: var(--text) !important;
  line-height: 1.5;
}

/* ---------- 联系 ---------- */

.band--contact { padding-bottom: 3rem; }
.contact__title { font-size: clamp(1.5rem, 4.4vw, 2rem); margin-bottom: 0.8rem; }
.contact__lead { color: var(--text-soft); max-width: 40rem; margin-bottom: 1.6rem; }

.qr { width: 12.5rem; height: 12.5rem; }
.qr--placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--card);
  border: 2px dashed #4a4a4a;
  color: var(--text-soft);
  font-size: 0.95rem;
}
img.qr {
  display: block;
  background: #ffffff;
  padding: 0.75rem;
  border-radius: 8px;
  width: 12.5rem;
  height: 12.5rem;
  object-fit: contain;
}

.contact__mail { margin-top: 1.2rem; font-size: 1rem; color: var(--text-soft); }
.contact__mail a { color: var(--text); text-decoration: none; }
.contact__mail a:hover { color: var(--text); }

/* ---------- 页脚 / 悬浮按钮 ---------- */

.foot {
  border-top: 1px solid var(--line);
  margin-top: 3rem;
  padding: 1.6rem clamp(1rem, 4vw, 2rem) calc(5.5rem + env(safe-area-inset-bottom));
  max-width: 68rem;
  margin-left: auto;
  margin-right: auto;
}
.foot__links {
  display: flex;
  flex-wrap: wrap;
  gap: 1.4rem;
  font-size: 0.95rem;
  margin-bottom: 0.9rem;
}
.foot__links a { color: var(--text-soft); text-decoration: none; }
.foot__links a:hover { color: var(--text); }
.foot__legal { font-size: 0.85rem; color: #7a7a7a; }

.sticky-cta {
  position: fixed;
  left: 1rem; right: 1rem;
  bottom: calc(0.9rem + env(safe-area-inset-bottom));
  background: #ffffff;
  color: #111111;
  text-align: center;
  text-decoration: none;
  font-size: 1.1rem;
  font-weight: 600;
  padding: 0.95rem 1rem;
  border-radius: 6px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.45);
}
.sticky-cta:hover { background: #d9d9d9; }
@media (min-width: 760px) {
  .sticky-cta { display: none; }
  .foot { padding-bottom: 1.8rem; }
}