/* ============================================================
   main.css — Dalog 主样式(桌面 ≥1024px 基线)
   配合 css/responsive.css 做响应式覆盖
   ============================================================ */

/* ----------------------------------------------------------
    通用工具类
    ---------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-pad-desktop);
}

.section {
  padding: var(--section-pad-desktop) 0;
}

.section--alt {
  background-color: var(--color-bg-soft);
}

.section__eyebrow {
  display: inline-block;
  font-size: var(--font-size-small);
  font-weight: var(--font-weight-semibold);
  color: var(--color-primary);
  background-color: var(--color-primary-soft);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  margin-bottom: var(--space-2);
}

.section__title {
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-2);
}

.section__subtitle {
  font-size: var(--font-size-body);
  color: var(--color-text-secondary);
  line-height: var(--line-height-normal);
  max-width: 720px;
}

.section__head {
  text-align: center;
  margin-bottom: var(--space-5);
}

.section__head .section__subtitle {
  margin: 0 auto;
}

/* ----------------------------------------------------------
    1. 顶部导航栏 .nav
    ---------------------------------------------------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background-color: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--color-border-soft);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav__brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: var(--font-weight-bold);
  font-size: 1.0625rem;
  color: var(--color-text-primary);
}

.nav__brand img {
  width: 32px;
  height: 32px;
}

.nav__menu {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.nav__link {
  position: relative;
  font-size: var(--font-size-small);
  color: var(--color-text-secondary);
  transition: color var(--duration-base) var(--ease-out);
}

.nav__link:hover,
.nav__link.is-active {
  color: var(--color-primary);
}

.nav__link.is-active::after {
  content: "";
  position: absolute;
  bottom: -22px;
  left: 50%;
  transform: translateX(-50%);
  width: 18px;
  height: 2px;
  background-color: var(--color-primary);
  border-radius: 2px;
}

.nav__cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  font-size: var(--font-size-small);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-md);
  transition: background-color var(--duration-base) var(--ease-out),
              transform var(--duration-base) var(--ease-out);
}

.nav__cta:hover {
  background-color: var(--color-primary-hover);
  transform: translateY(-1px);
}

.nav__burger {
  display: none;
  width: 40px;
  height: 40px;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
}

.nav__burger span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-text-primary);
  border-radius: 2px;
  transition: transform var(--duration-base) var(--ease-out),
              opacity var(--duration-base) var(--ease-out);
}

/* ----------------------------------------------------------
    2. Hero 首屏
    ---------------------------------------------------------- */
.hero {
  position: relative;
  padding: calc(var(--section-pad-desktop) - 16px) 0 var(--section-pad-desktop);
  background: var(--gradient-hero);
  color: var(--color-text-inverse);
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 30%, rgba(255,255,255,0.15), transparent 40%),
    radial-gradient(circle at 80% 70%, rgba(255,255,255,0.1), transparent 40%);
  pointer-events: none;
}

.hero__inner {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: var(--space-6);
  align-items: center;
  position: relative;
  z-index: var(--z-base);
}

.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background-color: rgba(255, 255, 255, 0.18);
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: var(--radius-full);
  font-size: var(--font-size-small);
  font-weight: var(--font-weight-medium);
  margin-bottom: var(--space-3);
}

.hero__eyebrow::before {
  content: "";
  width: 6px;
  height: 6px;
  background-color: #6FFFB0;
  border-radius: 50%;
  box-shadow: 0 0 8px #6FFFB0;
}

.hero__title {
  font-size: var(--font-size-hero);
  font-weight: var(--font-weight-bold);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-3);
}

.hero__title strong {
  background: linear-gradient(120deg, #FFD580, #FF9A3C);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__subtitle {
  font-size: clamp(1rem, 1.4vw, 1.25rem);
  color: rgba(255, 255, 255, 0.85);
  line-height: var(--line-height-loose);
  margin-bottom: var(--space-4);
  max-width: 540px;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-md);
  transition: all var(--duration-base) var(--ease-out);
  white-space: nowrap;
}

.btn--primary {
  background-color: var(--color-accent);
  color: var(--color-text-inverse);
  box-shadow: var(--shadow-cta);
}

.btn--primary:hover {
  background-color: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(255, 125, 0, 0.4);
}

.btn--ghost {
  background-color: rgba(255, 255, 255, 0.12);
  color: var(--color-text-inverse);
  border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn--ghost:hover {
  background-color: rgba(255, 255, 255, 0.2);
}

.btn--secondary {
  background-color: var(--color-bg);
  color: var(--color-primary);
  border: 1px solid var(--color-border);
}

.btn--secondary:hover {
  border-color: var(--color-primary);
  color: var(--color-primary-hover);
}

.btn--large {
  padding: 18px 40px;
  font-size: 1.125rem;
}

.btn--disabled {
  background-color: var(--color-bg-soft);
  color: var(--color-text-tertiary);
  border: 1px solid var(--color-border);
  cursor: not-allowed;
  box-shadow: none;
}

.btn--disabled:hover {
  transform: none;
  background-color: var(--color-bg-soft);
}

.hero__meta {
  display: flex;
  gap: var(--space-4);
  font-size: var(--font-size-small);
  color: rgba(255, 255, 255, 0.75);
}

.hero__meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.hero__meta-item::before {
  content: "✓";
  color: #6FFFB0;
  font-weight: var(--font-weight-bold);
}

/* Hero 手机预览 */
.hero__visual {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
}

.hero__phone {
  width: 280px;
  filter: drop-shadow(0 30px 50px rgba(0, 0, 0, 0.25));
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-12px); }
}

.hero__phone img {
  width: 100%;
  border-radius: 28px;
}

/* ----------------------------------------------------------
    3. 核心卖点 .selling-points
    ---------------------------------------------------------- */
.selling-points__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3);
}

.card {
  background-color: var(--color-bg-elevated);
  border: 1px solid var(--color-border-soft);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  transition: transform var(--duration-base) var(--ease-out),
              box-shadow var(--duration-base) var(--ease-out),
              border-color var(--duration-base) var(--ease-out);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary-soft);
}

.card__icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-hero);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-2);
  font-size: 24px;
}

.card__icon--orange { background: linear-gradient(135deg, #FF7D00, #FFB45A); }
.card__icon--purple { background: linear-gradient(135deg, #7C3AED, #A78BFA); }
.card__icon--pink   { background: linear-gradient(135deg, #EC4899, #F472B6); }
.card__icon--teal   { background: linear-gradient(135deg, #14B8A6, #5EEAD4); }
.card__icon--amber  { background: linear-gradient(135deg, #F59E0B, #FCD34D); }

.card__title {
  font-size: var(--font-size-h4);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-1);
}

.card__desc {
  font-size: var(--font-size-small);
  color: var(--color-text-secondary);
  line-height: var(--line-height-loose);
}

/* ----------------------------------------------------------
    4. 功能详解 .feature-block(图文左右交错)
    ---------------------------------------------------------- */
.feature-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
  align-items: center;
  padding: var(--space-6) 0;
}

.feature-block--reverse {
  direction: rtl;
}

.feature-block--reverse > * {
  direction: ltr;
}

.feature-block__text {
  max-width: 480px;
}

.feature-block__eyebrow {
  font-size: var(--font-size-small);
  font-weight: var(--font-weight-semibold);
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: var(--space-2);
}

.feature-block__title {
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-3);
}

.feature-block__desc {
  font-size: 1.0625rem;
  color: var(--color-text-secondary);
  line-height: var(--line-height-loose);
  margin-bottom: var(--space-3);
}

.feature-block__list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.feature-block__list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.feature-block__list li::before {
  content: "";
  flex-shrink: 0;
  width: 18px;
  height: 18px;
  margin-top: 3px;
  background: var(--color-primary-soft) url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='%23165DFF'><path d='M6.5 10.5L3 7l1.4-1.4 2.1 2.1 5.1-5.1L13 4z'/></svg>") center / 14px no-repeat;
  border-radius: 50%;
}

.feature-block__visual {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
}

.feature-block__visual img {
  width: 100%;
  max-width: 360px;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

/* ----------------------------------------------------------
    5. 截图轮播 .screenshots-carousel
    ---------------------------------------------------------- */
.carousel {
  position: relative;
  overflow: hidden;
  padding: var(--space-3) 0;
}

.carousel__track {
  display: flex;
  gap: var(--space-3);
  transition: transform var(--duration-slow) var(--ease-in-out);
  will-change: transform;
}

.carousel__slide {
  flex: 0 0 auto;
  width: 220px;
  scroll-snap-align: center;
}

.carousel__slide img {
  width: 100%;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  transition: transform var(--duration-base) var(--ease-out),
              box-shadow var(--duration-base) var(--ease-out);
}

.carousel__slide:hover img {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.carousel__caption {
  margin-top: var(--space-2);
  text-align: center;
  font-size: var(--font-size-small);
  color: var(--color-text-secondary);
  font-weight: var(--font-weight-medium);
}

.carousel__nav {
  display: flex;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-4);
}

.carousel__btn {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  color: var(--color-text-primary);
  font-size: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--duration-base) var(--ease-out);
}

.carousel__btn:hover {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  border-color: var(--color-primary);
}

.carousel__dots {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: var(--space-2);
}

.carousel__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--color-border);
  transition: all var(--duration-base) var(--ease-out);
  cursor: pointer;
}

.carousel__dot.is-active {
  background-color: var(--color-primary);
  width: 24px;
  border-radius: 4px;
}

/* ----------------------------------------------------------
    6. 下载区 .download
    ---------------------------------------------------------- */
.download {
  background: var(--gradient-hero);
  color: var(--color-text-inverse);
  position: relative;
  overflow: hidden;
}

.download::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 80% 20%, rgba(255,255,255,0.12), transparent 50%),
    radial-gradient(circle at 20% 80%, rgba(255,255,255,0.08), transparent 50%);
  pointer-events: none;
}

.download__inner {
  position: relative;
  z-index: var(--z-base);
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: var(--space-6);
  align-items: center;
}

.download__title {
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-2);
}

.download__desc {
  font-size: 1.0625rem;
  color: rgba(255, 255, 255, 0.85);
  line-height: var(--line-height-loose);
  margin-bottom: var(--space-4);
}

.download__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-3);
}

.download__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  font-size: var(--font-size-small);
  color: rgba(255, 255, 255, 0.75);
}

.download__meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.download__meta-item::before {
  content: "▸";
  color: #6FFFB0;
}

.download__qr {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.qr-card {
  background-color: var(--color-bg);
  border-radius: var(--radius-lg);
  padding: var(--space-3);
  text-align: center;
  color: var(--color-text-primary);
  box-shadow: var(--shadow-lg);
}

.qr-card__img {
  display: block;
  width: 160px;
  height: 160px;
  border-radius: var(--radius-md);
  margin: 0 auto var(--space-1);
  background-color: #fff;
  border: 1px solid var(--color-border-soft);
}

.qr-card__url {
  font-size: var(--font-size-xs);
  color: var(--color-text-tertiary);
  margin-top: 6px;
  font-family: ui-monospace, "SF Mono", Consolas, monospace;
}

.qr-card__label {
  font-size: var(--font-size-small);
  color: var(--color-text-secondary);
}

.qr-card__sub {
  font-size: var(--font-size-xs);
  color: var(--color-text-tertiary);
  margin-top: 2px;
}

/* ----------------------------------------------------------
    7. 页脚 .footer
    ---------------------------------------------------------- */
.footer {
  background-color: var(--color-bg-soft);
  padding: var(--space-5) 0 var(--space-3);
  border-top: 1px solid var(--color-border-soft);
}

.footer__grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: var(--space-4);
  margin-bottom: var(--space-4);
}

.footer__brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.footer__brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: var(--font-weight-bold);
  font-size: 1.0625rem;
}

.footer__brand-logo img {
  width: 32px;
  height: 32px;
}

.footer__brand-tag {
  font-size: var(--font-size-small);
  color: var(--color-text-secondary);
  max-width: 320px;
}

.footer__col-title {
  font-size: var(--font-size-small);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-primary);
  margin-bottom: var(--space-2);
}

.footer__list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer__list a {
  font-size: var(--font-size-small);
  color: var(--color-text-secondary);
  transition: color var(--duration-base) var(--ease-out);
}

.footer__list a:hover {
  color: var(--color-primary);
}

.footer__bottom {
  border-top: 1px solid var(--color-border-soft);
  padding-top: var(--space-3);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-2);
  font-size: var(--font-size-xs);
  color: var(--color-text-tertiary);
}

.footer__bottom-links {
  display: flex;
  gap: var(--space-3);
}

/* ----------------------------------------------------------
    8. 移动端浮动下载按钮 .fab-download(xs/sm 可见)
    ---------------------------------------------------------- */
.fab-download {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: var(--z-overlay);
  background-color: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
  border-top: 1px solid var(--color-border-soft);
  box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.06);
}

.fab-download__btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  padding: 14px 20px;
  background-color: var(--color-accent);
  color: var(--color-text-inverse);
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-cta);
}

/* 入场动画(简化版 AOS) */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s var(--ease-out), transform 0.6s var(--ease-out);
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}