/* ==========================================================================
   MacNas · 原理与设计 —— 与软件网页端同一套设计语言
   Material 风格 · 蓝色主色 · 纯色（不使用任何渐变）· 毛玻璃
   ========================================================================== */

:root {
  --primary: #0B57D0;
  --on-primary: #FFFFFF;
  --primary-hover: #0A4CB8;
  --primary-container: #D3E3FD;
  --on-primary-container: #041E49;
  --surface: #F7F9FC;
  --surface-2: #FFFFFF;
  --glass: rgba(255, 255, 255, 0.66);
  --glass-strong: rgba(255, 255, 255, 0.86);
  --glass-border: rgba(255, 255, 255, 0.72);
  --outline: rgba(31, 41, 55, 0.14);
  --outline-strong: rgba(31, 41, 55, 0.24);
  --on-surface: #1B1C1E;
  --on-surface-variant: #5A5F66;
  --hover: rgba(11, 87, 208, 0.07);
  --success: #16855C;
  --warning: #B26A00;
  --danger: #B3261E;
  --code-bg: rgba(11, 87, 208, 0.06);
  --shadow-1: 0 1px 2px rgba(16, 24, 40, 0.07), 0 1px 3px rgba(16, 24, 40, 0.08);
  --shadow-2: 0 8px 22px rgba(16, 24, 40, 0.12), 0 2px 6px rgba(16, 24, 40, 0.07);
  --shadow-3: 0 24px 60px rgba(16, 24, 40, 0.22);
  --radius-sm: 10px;
  --radius: 14px;
  --radius-lg: 20px;
  --blur: saturate(180%) blur(24px);
  --maxw: 1180px;
}

html[data-theme="dark"] {
  --primary: #A8C7FA;
  --on-primary: #062E6F;
  --primary-hover: #C2D8FB;
  --primary-container: #0842A0;
  --on-primary-container: #D3E3FD;
  --surface: #0E1318;
  --surface-2: #151B22;
  --glass: rgba(28, 34, 42, 0.66);
  --glass-strong: rgba(24, 30, 38, 0.86);
  --glass-border: rgba(255, 255, 255, 0.10);
  --outline: rgba(255, 255, 255, 0.14);
  --outline-strong: rgba(255, 255, 255, 0.24);
  --on-surface: #E6E9EE;
  --on-surface-variant: #A8B0BA;
  --hover: rgba(168, 199, 250, 0.10);
  --code-bg: rgba(168, 199, 250, 0.10);
  --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-2: 0 8px 22px rgba(0, 0, 0, 0.45);
  --shadow-3: 0 24px 60px rgba(0, 0, 0, 0.55);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 86px; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI",
               "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 15px;
  line-height: 1.75;
  color: var(--on-surface);
  background: var(--surface);
  -webkit-font-smoothing: antialiased;
}

/* 背景装饰：纯色圆斑 + 模糊，不使用渐变 */
.bg-deco {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}
.bg-deco::before,
.bg-deco::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: 0.40;
}
.bg-deco::before {
  width: 620px; height: 620px;
  top: -220px; left: -160px;
  background: var(--primary-container);
}
.bg-deco::after {
  width: 520px; height: 520px;
  bottom: -180px; right: -120px;
  background: var(--primary-container);
  opacity: 0.28;
}

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

code, .mono, pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.88em;
}
code {
  background: var(--code-bg);
  padding: 1px 6px;
  border-radius: 6px;
  color: var(--on-surface);
  word-break: break-word;
}

/* ---------------- 顶部导航 ---------------- */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  border-bottom: 1px solid var(--outline);
}
.glass {
  background: var(--glass);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
}
.topbar-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 10px 22px;
  display: flex;
  align-items: center;
  gap: 18px;
}
.brand { display: flex; align-items: center; gap: 10px; color: inherit; }
.brand:hover { text-decoration: none; }
.brand-logo { width: 32px; height: 32px; border-radius: 9px; box-shadow: var(--shadow-1); }
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text strong { font-size: 15px; letter-spacing: .2px; }
.brand-text small { font-size: 11px; color: var(--on-surface-variant); }

.topnav {
  display: flex;
  gap: 4px;
  flex: 1;
  flex-wrap: wrap;
  overflow: hidden;
}
.topnav a {
  font-size: 12.5px;
  color: var(--on-surface-variant);
  padding: 6px 10px;
  border-radius: 999px;
  white-space: nowrap;
}
.topnav a:hover { background: var(--hover); color: var(--primary); text-decoration: none; }
.topnav a.active { background: var(--primary-container); color: var(--on-primary-container); font-weight: 600; }

.topbar-actions { display: flex; align-items: center; gap: 8px; }

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  height: 36px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  background: transparent;
  color: var(--primary);
  transition: background .15s ease;
}
.btn:hover { background: var(--hover); text-decoration: none; }
.btn.filled { background: var(--primary); color: var(--on-primary); box-shadow: var(--shadow-1); }
.btn.filled:hover { background: var(--primary-hover); }
.btn.text { border-color: var(--outline); color: var(--on-surface); }
.icon-btn {
  width: 34px; height: 34px;
  border-radius: 50%;
  border: none;
  background: transparent;
  color: var(--on-surface-variant);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.icon-btn:hover { background: var(--hover); color: var(--primary); }
.icon-btn svg { width: 18px; height: 18px; }

/* ---------------- 首屏 ---------------- */
.hero {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 56px 22px 24px;
}
.hero-card {
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 44px 40px 38px;
  box-shadow: var(--shadow-2);
  text-align: center;
}
.hero-logo {
  width: 84px; height: 84px;
  border-radius: 22px;
  box-shadow: var(--shadow-2);
}
.hero h1 {
  margin: 18px 0 10px;
  font-size: 40px;
  letter-spacing: -.5px;
}
.hero-lead {
  margin: 0 auto;
  max-width: 760px;
  font-size: 16px;
  color: var(--on-surface-variant);
}
.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin: 22px 0 24px;
}
.tag-pill {
  font-size: 12px;
  font-weight: 600;
  color: var(--on-primary-container);
  background: var(--primary-container);
  padding: 5px 12px;
  border-radius: 999px;
}
.hero-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; }

/* ---------------- 区块 ---------------- */
.block {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 44px 22px;
}
.section-head {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 22px;
}
.section-index {
  flex: none;
  font-size: 13px;
  font-weight: 700;
  color: var(--on-primary-container);
  background: var(--primary-container);
  width: 40px; height: 40px;
  border-radius: 12px;
  display: grid;
  place-items: center;
}
.section-head h2 {
  margin: 2px 0 6px;
  font-size: 25px;
  letter-spacing: -.3px;
}
.section-sub { margin: 0; color: var(--on-surface-variant); font-size: 14px; }

.prose > p { margin: 0 0 16px; }
.prose > p:last-child { margin-bottom: 0; }

.callout {
  border-left: 3px solid var(--primary);
  background: var(--glass);
  backdrop-filter: var(--blur);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 14px 18px;
  margin: 20px 0 0 !important;
}

/* ---------------- 卡片 / 面板 ---------------- */
.cards { display: grid; gap: 16px; margin: 18px 0 22px; }
.cards.two { grid-template-columns: repeat(2, 1fr); }
.cards.three { grid-template-columns: repeat(3, 1fr); }
.card {
  background: var(--glass);
  backdrop-filter: var(--blur);
  border: 1px solid var(--outline);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow-1);
}
.card h3 { margin: 12px 0 8px; font-size: 15.5px; }
.card p { margin: 0; font-size: 13.5px; color: var(--on-surface-variant); }
.card-icon {
  width: 40px; height: 40px;
  border-radius: 12px;
  background: var(--primary-container);
  color: var(--primary);
  display: grid;
  place-items: center;
}
.card-icon svg { width: 22px; height: 22px; }
.steps.mono li { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 12.6px; }
.c-dim { color: var(--on-surface-variant); }

/* ---------------- 收尾 ---------------- */
.finale {
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 34px 32px;
  box-shadow: var(--shadow-2);
}
.finale h2 { margin: 0 0 12px; font-size: 22px; }
.finale p { margin: 0 0 20px; color: var(--on-surface-variant); }

.foot { border-top: 1px solid var(--outline); margin-top: 20px; }
.foot-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 22px;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  font-size: 12.5px;
  color: var(--on-surface-variant);
}

/* ---------------- 自适应 ---------------- */
@media (max-width: 980px) {
  .cards.two, .cards.three { grid-template-columns: 1fr; }
  .topnav { display: none; }
  .hero h1 { font-size: 32px; }
  .hero-card { padding: 32px 22px 28px; }
}
@media (max-width: 620px) {
  body { font-size: 14.5px; }
  .block { padding: 32px 16px; }
  .hero { padding: 28px 16px 12px; }
  .section-head h2 { font-size: 21px; }
}

/* ---------------- 首屏小字（芯片选择提示） ---------------- */
.hero-note {
  margin: 16px auto 0;
  max-width: 760px;
  font-size: 12.5px;
  color: var(--on-surface-variant);
}

/* ---------------- 下载卡片 ---------------- */
.download-card { display: flex; flex-direction: column; align-items: flex-start; }
.download-card h3 { margin-bottom: 6px; }
.download-card .btn { margin-top: 12px; }
.download-card .mono {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 11.5px;
  margin: 4px 0 0;
}

/* ---------------- 快速上手：编号步骤 ---------------- */
.guide-steps { display: flex; flex-direction: column; gap: 16px; margin: 4px 0 24px; }
.guide-step { display: flex; gap: 14px; align-items: flex-start; }
.guide-step-no {
  flex: none;
  width: 28px;
  height: 28px;
  border-radius: 9px;
  display: grid;
  place-items: center;
  background: var(--primary-container);
  color: var(--primary);
  font-size: 13px;
  font-weight: 700;
}
.guide-step h3 { margin: 2px 0 5px; font-size: 15px; }
.guide-step p { margin: 0; font-size: 13.5px; color: var(--on-surface-variant); }

@media (max-width: 640px) {
  .guide-step { gap: 10px; }
  .download-card .btn { width: 100%; }
}