/* ==========================================================================
   Hyico · Layout
   容器、栅格、分区节奏、页头页脚与抽屉的骨架定位。
   ========================================================================== */

/* ---------- 容器 ---------- */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.wrap--narrow { max-width: var(--wrap-narrow); }
.wrap--wide { max-width: 1400px; }
.wrap--flush { padding-inline: 0; }

/* ---------- 分区 ---------- */
.section {
  padding-block: var(--section-y);
  position: relative;
}

.section--tight { padding-block: clamp(2.5rem, 1.6rem + 3.5vw, 4.5rem); }
.section--flush-top { padding-block-start: 0; }
.section--flush-bottom { padding-block-end: 0; }
.section--sub { background-color: var(--bg-sub); }

/* 细线分区，替代粗重色块 */
.section--ruled { border-top: 1px solid var(--border); }

.section__head {
  display: grid;
  gap: var(--s-4);
  max-width: 62ch;
  margin-bottom: clamp(2rem, 1.4rem + 2vw, 3.5rem);
}

.section__head--center {
  justify-items: center;
  text-align: center;
  margin-inline: auto;
}

.section__head p {
  font-size: var(--fs-lede);
  color: var(--text-2);
  line-height: 1.7;
}

/* 章节标题行：左标题 + 右说明 */
.section__split {
  display: grid;
  gap: var(--s-5) var(--s-12);
  align-items: end;
  margin-bottom: clamp(2rem, 1.4rem + 2vw, 3.5rem);
}

/* ---------- 通用栅格 ---------- */
.grid { display: grid; gap: var(--s-5); }

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.grid--gap-lg { gap: var(--s-8); }
.grid--gap-sm { gap: var(--s-3); }

/* 侧栏布局：主内容 + 侧栏 */
.split {
  display: grid;
  gap: clamp(2rem, 1.2rem + 3vw, 4rem);
}

/* ---------- Bento：不等宽卡片网格 ---------- */
.bento {
  display: grid;
  gap: var(--s-4);
  grid-template-columns: repeat(6, minmax(0, 1fr));
}

.bento > * { grid-column: span 6; }

/* ---------- 栈式布局工具 ---------- */
.stack { display: grid; gap: var(--s-4); }
.stack--sm { gap: var(--s-2); }
.stack--lg { gap: var(--s-8); }
.stack--center { justify-items: center; text-align: center; }

.row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-3);
  align-items: center;
}

.row--between { justify-content: space-between; }
.row--end { justify-content: flex-end; }

/* ==========================================================================
   页头
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: var(--glass);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur-2) var(--ease), box-shadow var(--dur-2) var(--ease);
}

/* 滚动后才出现分隔线，初始状态更干净 */
.site-header.is-scrolled {
  border-bottom-color: var(--border);
  box-shadow: 0 1px 0 rgba(33, 54, 48, 0.02);
}

.site-header__inner {
  display: flex;
  align-items: center;
  gap: var(--s-5);
  min-height: var(--header-h);
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: var(--s-2);
  margin-inline-start: auto;
}

/* ==========================================================================
   主内容
   ========================================================================== */
main { display: block; }

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer {
  padding-block: clamp(3rem, 2rem + 4vw, 5rem) var(--s-8);
  background-color: var(--bg-sub);
  border-top: 1px solid var(--border);
  color: var(--text-2);
  font-size: var(--fs-sm);
}

.site-footer__grid {
  display: grid;
  gap: var(--s-10) var(--s-8);
}

.site-footer__brand { display: grid; gap: var(--s-4); max-width: 34ch; }

.site-footer__cols {
  display: grid;
  gap: var(--s-8);
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
}

.site-footer__col h3 {
  font-size: var(--fs-xs);
  font-weight: var(--fw-semi);
  letter-spacing: var(--ls-wide);
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: var(--s-3);
}

.site-footer__col ul { list-style: none; padding: 0; display: grid; gap: var(--s-2); }

.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-3) var(--s-6);
  align-items: center;
  justify-content: space-between;
  margin-top: var(--s-10);
  padding-top: var(--s-6);
  border-top: 1px solid var(--border);
  color: var(--text-3);
}

.site-footer__legal { display: flex; flex-wrap: wrap; gap: var(--s-2) var(--s-5); }
.site-footer__legal a { color: inherit; text-decoration: none; }
.site-footer__legal a:hover { color: var(--accent-strong); }

/* ==========================================================================
   抽屉（移动端导航）
   ========================================================================== */
.drawer {
  position: fixed;
  inset: var(--header-h) 0 0;
  z-index: var(--z-drawer);
  display: flex;
  flex-direction: column;
  gap: var(--s-6);
  padding: var(--s-6) var(--gutter) var(--s-10);
  background: var(--bg);
  overflow-y: auto;
  overscroll-behavior: contain;
  opacity: 0;
  transform: translateY(-8px);
  transition: opacity var(--dur-2) var(--ease), transform var(--dur-2) var(--ease-out);
}

.drawer[hidden] { display: none !important; }

.drawer.is-open { opacity: 1; transform: translateY(0); }

.drawer__nav { display: grid; gap: var(--s-1); }

.drawer__group { border-bottom: 1px solid var(--border); }

.drawer__link,
.drawer__toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-3);
  width: 100%;
  padding: var(--s-4) 0;
  font-size: var(--fs-lg);
  font-weight: var(--fw-medium);
  color: var(--text);
  text-decoration: none;
  text-align: start;
}

.drawer__link[aria-current="page"] { color: var(--accent-strong); }

.drawer__sub {
  display: grid;
  gap: var(--s-1);
  padding-bottom: var(--s-3);
  padding-inline-start: var(--s-4);
  border-inline-start: 1px solid var(--border);
  margin-bottom: var(--s-2);
}

.drawer__sub a {
  padding: var(--s-2) 0;
  font-size: var(--fs-base);
  color: var(--text-2);
  text-decoration: none;
}

.drawer__sub a:hover { color: var(--accent-strong); }

.drawer__foot {
  display: grid;
  gap: var(--s-3);
  padding-top: var(--s-4);
  margin-top: auto;
  font-size: var(--fs-sm);
  /* 用 --text-2 而非 --text-3：邮箱需要满足正文对比度，不只是装饰 */
  color: var(--text-2);
}

/* ==========================================================================
   Hero 布局
   ========================================================================== */
.hero {
  position: relative;
  padding-block: clamp(3rem, 1.5rem + 7vw, 7rem) clamp(3.5rem, 2rem + 6vw, 7rem);
  overflow: hidden;
}

/* 背景网格：极淡的工程坐标纸 */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 20%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 20%, transparent 78%);
  pointer-events: none;
}

/* 品牌色柔和光晕 */
.hero::after {
  content: "";
  position: absolute;
  top: -30%;
  inset-inline-end: -10%;
  width: min(780px, 90vw);
  aspect-ratio: 1;
  background: radial-gradient(circle at 50% 50%,
    color-mix(in srgb, var(--mint-200) 34%, transparent) 0%,
    color-mix(in srgb, var(--mint-100) 22%, transparent) 38%,
    transparent 70%);
  filter: blur(10px);
  pointer-events: none;
}

.hero__inner { position: relative; z-index: var(--z-base); }

/* ==========================================================================
   断点
   ========================================================================== */
@media (min-width: 640px) {
  .grid--2\@sm { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .bento > .b-3 { grid-column: span 3; }
}

@media (min-width: 900px) {
  .site-footer__grid { grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr); }
  .split { grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); }
  .split--aside-left { grid-template-columns: minmax(0, 1fr) minmax(0, 1.3fr); }
  .split--wide-main { grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr); }
  .section__split { grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr); }

  .hero__inner { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); gap: clamp(2rem, 4vw, 4.5rem); align-items: center; }

  .bento > .b-2 { grid-column: span 2; }
  .bento > .b-3 { grid-column: span 3; }
  .bento > .b-4 { grid-column: span 4; }
  .bento > .b-5 { grid-column: span 5; }
}

@media (max-width: 899px) {
  .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 639px) {
  :root { --header-h: 58px; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .site-footer__bottom { justify-content: flex-start; }
}