/* ==========================================================================
   光绘 · 下载首页样式
   风格：深色底 + 紫蓝渐变 + 多彩高亮 + 大圆角
   ========================================================================== */

:root {
  /* 背景层级 */
  --bg: #08080a;
  --bg-2: #0c0c10;
  --card: rgba(23, 23, 27, 0.72);
  --card-solid: #15151a;

  /* 描边 */
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.16);

  /* 文字 */
  --text: #ededf0;
  --text-dim: #a0a0ab;
  --text-mute: #6a6a73;

  /* 多彩高亮 */
  --accent: #3b6ef5;
  --purple: #8b5cf6;
  --cyan: #22d3ee;
  --gold: #e8b33c;
  --pink: #f472b6;
  --green: #35c46b;

  /* 圆角 */
  --r-xl: 28px;
  --r-lg: 22px;
  --r-md: 14px;
  --r-sm: 10px;
  --r-pill: 999px;

  /* 阴影 */
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.55);
  --shadow-sm: 0 10px 30px rgba(0, 0, 0, 0.35);

  /* 内容宽度 */
  --maxw: 1160px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: "HarmonyOS Sans SC", "Inter", "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
  font-size: 15px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
}

/* 渐变文字：紫 → 蓝 → 青 */
.grad-text {
  background: linear-gradient(100deg, var(--purple) 0%, var(--accent) 45%, var(--cyan) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ---------- 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  height: 50px;
  padding: 0 26px;
  border-radius: var(--r-pill);
  font-size: 15px;
  font-weight: 600;
  white-space: nowrap;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn .ico {
  width: 19px;
  height: 19px;
  flex: none;
}

.btn-primary {
  color: #fff;
  background: linear-gradient(100deg, var(--purple), var(--accent) 55%, var(--cyan));
  box-shadow: 0 12px 34px rgba(59, 110, 245, 0.42);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 46px rgba(59, 110, 245, 0.55);
}

.btn-ghost {
  color: var(--text);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-strong);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.1);
  transform: translateY(-2px);
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   顶部导航
   ========================================================================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  transition: background 0.25s ease, border-color 0.25s ease;
  border-bottom: 1px solid transparent;
}

/* 滚动后加玻璃底：由 JS 切换 is-stuck */
.nav.is-stuck {
  background: rgba(8, 8, 10, 0.78);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom-color: var(--border);
}

.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  height: 68px;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 28px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: none;
}

.brand-logo {
  width: 32px;
  height: 32px;
  border-radius: 9px;
}

.brand-name {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 26px;
  margin-left: auto;
  font-size: 14px;
  color: var(--text-dim);
}

.nav-links a {
  transition: color 0.15s ease;
}

.nav-links a:hover {
  color: var(--text);
}

.nav-cta {
  flex: none;
  height: 38px;
  padding: 0 20px;
  display: inline-flex;
  align-items: center;
  border-radius: var(--r-pill);
  font-size: 14px;
  font-weight: 600;
  color: #fff;
  background: linear-gradient(100deg, var(--purple), var(--accent));
  box-shadow: 0 8px 24px rgba(59, 110, 245, 0.38);
  transition: transform 0.15s ease;
}

.nav-cta:hover {
  transform: translateY(-1px);
}

/* ==========================================================================
   首屏
   ========================================================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  overflow: hidden;
  /* 三层叠加：暗角遮罩 → 品牌蓝光晕 → 极光背景图 */
  background-color: var(--bg);
  background-image:
    radial-gradient(1100px 620px at 50% 42%, rgba(8, 8, 10, 0.34), rgba(8, 8, 10, 0.86) 74%),
    radial-gradient(900px 460px at 50% -8%, rgba(139, 92, 246, 0.22), transparent 68%),
    url("assets/bg-aurora.jpg");
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
}

/* 底部渐隐，和下一个区块自然衔接 */
.hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 180px;
  background: linear-gradient(to bottom, transparent, var(--bg));
  pointer-events: none;
}

.hero-glow {
  position: absolute;
  width: 780px;
  height: 780px;
  left: 50%;
  top: 46%;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, rgba(59, 110, 245, 0.22), transparent 62%);
  filter: blur(30px);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 2;
  max-width: 820px;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 34px;
  padding: 0 16px;
  border-radius: var(--r-pill);
  font-size: 13px;
  color: #c9d6ff;
  background: rgba(59, 110, 245, 0.14);
  border: 1px solid rgba(59, 110, 245, 0.32);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.hero-badge .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 10px var(--cyan);
}

.hero-title {
  margin-top: 26px;
  font-size: clamp(42px, 7vw, 76px);
  line-height: 1.1;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.hero-sub {
  margin: 24px auto 0;
  max-width: 620px;
  font-size: 16px;
  color: var(--text-dim);
}

.hero-actions {
  margin-top: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
}

.hero-meta {
  margin-top: 26px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  font-size: 13px;
  color: var(--text-mute);
  flex-wrap: wrap;
}

.hero-meta i {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: var(--text-mute);
}

/* ==========================================================================
   通用区块
   ========================================================================== */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 96px 24px;
}

.section-head {
  text-align: center;
  max-width: 660px;
  margin: 0 auto 54px;
}

.eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

.section-head h2 {
  margin-top: 12px;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  letter-spacing: -0.01em;
}

.section-head p {
  margin-top: 14px;
  color: var(--text-dim);
  font-size: 15.5px;
}

/* ==========================================================================
   作品展示
   ========================================================================== */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.g-item {
  position: relative;
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--card-solid);
  border: 1px solid var(--border);
  aspect-ratio: 1 / 1;
  box-shadow: var(--shadow-sm);
}

.g-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.g-item:hover img {
  transform: scale(1.06);
}

/* ==========================================================================
   功能特性
   ========================================================================== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.f-card {
  position: relative;
  padding: 28px 26px 30px;
  border-radius: var(--r-lg);
  background: var(--card);
  border: 1px solid var(--border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  overflow: hidden;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.f-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-strong);
}

/* 每张卡片顶部一条彩色高亮，颜色由 c-* 类决定 */
.f-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 26px;
  right: 26px;
  height: 2px;
  border-radius: 0 0 3px 3px;
  opacity: 0.9;
}

.c-purple::before { background: linear-gradient(90deg, transparent, var(--purple), transparent); }
.c-blue::before   { background: linear-gradient(90deg, transparent, var(--accent), transparent); }
.c-cyan::before   { background: linear-gradient(90deg, transparent, var(--cyan), transparent); }
.c-gold::before   { background: linear-gradient(90deg, transparent, var(--gold), transparent); }
.c-pink::before   { background: linear-gradient(90deg, transparent, var(--pink), transparent); }
.c-green::before  { background: linear-gradient(90deg, transparent, var(--green), transparent); }

.f-ico {
  width: 46px;
  height: 46px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--r-md);
  margin-bottom: 18px;
}

.f-ico svg {
  width: 23px;
  height: 23px;
}

.c-purple .f-ico { color: var(--purple); background: rgba(139, 92, 246, 0.14); }
.c-blue .f-ico   { color: #6f9bff; background: rgba(59, 110, 245, 0.16); }
.c-cyan .f-ico   { color: var(--cyan); background: rgba(34, 211, 238, 0.13); }
.c-gold .f-ico   { color: var(--gold); background: rgba(232, 179, 60, 0.14); }
.c-pink .f-ico   { color: var(--pink); background: rgba(244, 114, 182, 0.14); }
.c-green .f-ico  { color: var(--green); background: rgba(53, 196, 107, 0.14); }

.f-card h3 {
  font-size: 17.5px;
  font-weight: 650;
}

.f-card p {
  margin-top: 10px;
  font-size: 14px;
  color: var(--text-dim);
  line-height: 1.75;
}

/* ==========================================================================
   下载安装
   ========================================================================== */
.dl-wrap {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 26px;
  align-items: start;
}

.dl-card {
  padding: 32px 30px;
  border-radius: var(--r-xl);
  background: linear-gradient(180deg, rgba(139, 92, 246, 0.1), rgba(23, 23, 27, 0.86) 42%);
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow);
}

.dl-card-head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 26px;
}

.dl-logo {
  width: 52px;
  height: 52px;
  border-radius: var(--r-md);
  flex: none;
}

.dl-card-head h3 {
  font-size: 20px;
  font-weight: 700;
}

.dl-spec {
  list-style: none;
  margin-top: 24px;
  border-top: 1px solid var(--border);
}

.dl-spec li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 13px 2px;
  font-size: 14px;
  border-bottom: 1px solid var(--border);
}

.dl-spec li span {
  color: var(--text-mute);
}

.dl-spec li b {
  font-weight: 600;
}

.steps {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.steps li {
  display: flex;
  gap: 16px;
  padding: 20px 22px;
  border-radius: var(--r-lg);
  background: var(--card);
  border: 1px solid var(--border);
}

.step-no {
  flex: none;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  font-size: 15px;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(135deg, var(--purple), var(--accent));
}

.steps h4 {
  font-size: 16px;
  font-weight: 650;
}

.steps p {
  margin-top: 6px;
  font-size: 14px;
  color: var(--text-dim);
}

.steps b {
  color: var(--text);
  font-weight: 600;
}

/* ==========================================================================
   常见问题
   ========================================================================== */
.faq-list {
  max-width: 820px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  border-radius: var(--r-lg);
  background: var(--card);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: border-color 0.2s ease;
}

.faq-item[open] {
  border-color: var(--border-strong);
}

.faq-item summary {
  padding: 20px 24px;
  font-size: 15.5px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

/* 自绘展开箭头 */
.faq-item summary::after {
  content: "";
  flex: none;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--text-mute);
  border-bottom: 2px solid var(--text-mute);
  transform: rotate(45deg);
  transition: transform 0.2s ease;
  margin-top: -4px;
}

.faq-item[open] summary::after {
  transform: rotate(-135deg);
  margin-top: 4px;
}

.faq-item p {
  padding: 0 24px 22px;
  font-size: 14.5px;
  color: var(--text-dim);
}

/* ==========================================================================
   用户交流群
   ========================================================================== */
.group-card {
  max-width: 840px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 232px 1fr;
  gap: 38px;
  align-items: center;
  padding: 34px 38px;
  border-radius: var(--r-xl);
  background: linear-gradient(180deg, rgba(34, 211, 238, 0.09), rgba(23, 23, 27, 0.86) 46%);
  border: 1px solid var(--border-strong);
  box-shadow: var(--shadow);
}

/* 二维码本身带深灰底与白底圆角，直接圆角裁切即可融进深色卡片 */
.group-qr-box {
  border-radius: var(--r-lg);
  overflow: hidden;
  border: 1px solid var(--border-strong);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.45);
}

.group-qr {
  width: 100%;
  display: block;
}

.group-info h3 {
  font-size: 20px;
  font-weight: 700;
}

.group-desc {
  margin-top: 12px;
  font-size: 14.5px;
  color: var(--text-dim);
  line-height: 1.8;
}

.group-points {
  list-style: none;
  margin-top: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.group-points li {
  position: relative;
  padding-left: 22px;
  font-size: 14px;
  color: var(--text-dim);
}

.group-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--purple), var(--cyan));
}

/* ==========================================================================
   页脚
   ========================================================================== */
.footer {
  border-top: 1px solid var(--border);
  background: var(--bg-2);
}

.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 46px 24px;
  text-align: center;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-size: 17px;
  font-weight: 700;
}

.footer-brand img {
  width: 28px;
  height: 28px;
  border-radius: 8px;
}

.footer-desc {
  margin-top: 10px;
  font-size: 14px;
  color: var(--text-dim);
}

.footer-copy {
  margin-top: 18px;
  font-size: 13px;
  color: var(--text-mute);
}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 960px) {
  .gallery-grid,
  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .dl-wrap {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 720px) {
  .nav-links {
    display: none;
  }

  .section {
    padding: 72px 20px;
  }

  .hero {
    padding: 108px 20px 64px;
  }

  .gallery-grid,
  .feature-grid {
    grid-template-columns: 1fr;
  }

  /* 窄屏下二维码改为上下堆叠，二维码居中且限制宽度 */
  .group-card {
    grid-template-columns: 1fr;
    gap: 26px;
    padding: 28px 24px;
  }

  .group-qr-box {
    max-width: 220px;
    margin: 0 auto;
  }

  .hero-actions .btn {
    width: 100%;
  }
}