/* ==========================================================================
   三联慧学官网 —— 样式
   纯静态、无构建、无外链字体；配色取自 App 内的蓝白主色 + Logo 上的橙色点缀。
   ========================================================================== */

:root {
  --blue-700: #0b5ad9;
  --blue-600: #1677ff;
  --blue-500: #3a97ff;
  --blue-100: #e6f0ff;
  --blue-50: #f2f7ff;
  --orange: #ff8a3d;
  --ink: #0d1b2a;
  --ink-2: #22364d;
  --muted: #5f7386;
  --line: #e3ebf6;
  --bg: #ffffff;
  --tint: #f5f9ff;
  --radius: 20px;
  --radius-sm: 12px;
  --shadow-s: 0 1px 2px rgba(13, 27, 42, .06), 0 4px 14px rgba(13, 27, 42, .06);
  --shadow-m: 0 10px 30px rgba(11, 90, 217, .12), 0 2px 8px rgba(13, 27, 42, .06);
  --shadow-l: 0 30px 70px rgba(11, 90, 217, .22), 0 8px 24px rgba(13, 27, 42, .10);
  --wrap: 1180px;
  --nav-h: 68px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 16px); }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Noto Sans SC", "Source Han Sans SC", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
h1, h2, h3 { margin: 0; line-height: 1.24; letter-spacing: -.01em; }
p { margin: 0; }
code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: .88em;
  background: var(--blue-50);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 1px 6px;
  color: var(--blue-700);
}
.wrap { width: 100%; max-width: var(--wrap); margin: 0 auto; padding: 0 22px; }

/* ---------------------------------------------------------------- 按钮 */
.btn {
  --btn-bg: transparent;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 11px 20px;
  border: 1px solid transparent;
  border-radius: 999px;
  background: var(--btn-bg);
  font-size: 15px;
  font-weight: 600;
  line-height: 1;
  cursor: pointer;
  white-space: nowrap;
  transition: transform .18s ease, box-shadow .22s ease, background-color .2s ease, border-color .2s ease, color .2s ease;
}
.btn svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.9; stroke-linecap: round; stroke-linejoin: round; }
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn:focus-visible { outline: 3px solid rgba(22, 119, 255, .35); outline-offset: 2px; }

.btn--primary {
  background: linear-gradient(135deg, var(--blue-600), var(--blue-500));
  color: #fff;
  box-shadow: 0 6px 18px rgba(22, 119, 255, .32);
}
.btn--primary:hover { box-shadow: 0 12px 26px rgba(22, 119, 255, .40); }
.btn--ghost {
  background: #fff;
  border-color: var(--line);
  color: var(--ink-2);
  box-shadow: var(--shadow-s);
}
.btn--ghost:hover { border-color: #c9dcf7; color: var(--blue-700); }
.btn--white { background: #fff; color: var(--blue-700); box-shadow: 0 10px 24px rgba(6, 40, 90, .22); }
.btn--white:hover { background: #f4f9ff; }
.btn--sm { padding: 9px 16px; font-size: 14px; }
.btn--lg { padding: 15px 26px; font-size: 16px; }
.btn__sub { font-weight: 700; opacity: .85; font-size: .9em; }

/* ---------------------------------------------------------------- 导航 */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 60;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, .72);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s ease, box-shadow .25s ease, background-color .25s ease;
}
.nav.is-stuck { border-bottom-color: var(--line); box-shadow: 0 6px 22px rgba(13, 27, 42, .06); background: rgba(255, 255, 255, .9); }
.nav__inner { display: flex; align-items: center; gap: 20px; }
.brand { display: flex; align-items: center; flex: none; }
.brand__logo { height: 34px; width: auto; }

.nav__links { display: flex; align-items: center; gap: 4px; margin-left: 8px; }
.nav__links a {
  padding: 8px 13px;
  border-radius: 999px;
  font-size: 15px;
  color: var(--ink-2);
  transition: background-color .18s ease, color .18s ease;
}
.nav__links a:hover { background: var(--blue-50); color: var(--blue-700); }

.nav__right { display: flex; align-items: center; gap: 12px; margin-left: auto; }
.ver-chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-2);
  font-variant-numeric: tabular-nums;
}
.ver-chip .dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: #23c26b;
  box-shadow: 0 0 0 3px rgba(35, 194, 107, .18);
}
.nav__burger { display: none; }

/* ---------------------------------------------------------------- 首屏 */
.hero { position: relative; padding: calc(var(--nav-h) + 62px) 0 84px; overflow: hidden; }
.hero__bg {
  position: absolute;
  inset: -10% -10% auto -10%;
  height: 130%;
  background:
    radial-gradient(60% 55% at 78% 8%, rgba(58, 151, 255, .30), transparent 62%),
    radial-gradient(45% 45% at 8% 22%, rgba(255, 138, 61, .16), transparent 68%),
    linear-gradient(180deg, var(--blue-50), #fff 62%);
  z-index: -1;
}
.hero__inner { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.02fr); gap: 52px; align-items: center; }

.pill {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 16px 6px 6px;
  border: 1px solid #d5e5fb;
  border-radius: 999px;
  background: rgba(255, 255, 255, .85);
  box-shadow: var(--shadow-s);
  font-size: 13.5px;
  color: var(--ink-2);
}
.pill__tag {
  padding: 3px 10px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--blue-600), var(--blue-500));
  color: #fff;
  font-size: 11.5px;
  font-weight: 800;
  letter-spacing: .06em;
}
.hero h1 { margin-top: 22px; font-size: clamp(34px, 4.4vw, 54px); font-weight: 800; }
.hero h1 em {
  display: block;
  margin-top: 10px;
  font-size: .52em;
  font-style: normal;
  font-weight: 700;
  color: var(--blue-700);
}
.hero__desc { margin-top: 20px; max-width: 34em; font-size: 16.5px; color: var(--muted); }
.hero__desc b { color: var(--ink-2); }
.hero__cta { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 30px; }

.hero__facts {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 34px;
  margin: 36px 0 0;
  padding: 22px 0 0;
  border-top: 1px solid var(--line);
  list-style: none;
}
.hero__facts li { display: flex; flex-direction: column; }
.hero__facts b { font-size: 19px; font-weight: 800; color: var(--blue-700); font-variant-numeric: tabular-nums; }
.hero__facts span { font-size: 13px; color: var(--muted); }

/* 设备框：桌面窗口 + 手机 */
.hero__stage { position: relative; padding-bottom: 34px; }
.win {
  border-radius: 14px;
  overflow: hidden;
  background: #fff;
  box-shadow: var(--shadow-l);
  border: 1px solid rgba(13, 27, 42, .07);
}
.win__bar {
  display: flex;
  align-items: center;
  gap: 7px;
  height: 34px;
  padding: 0 12px;
  background: #f2f5fa;
  border-bottom: 1px solid var(--line);
}
.win__bar i { width: 10px; height: 10px; border-radius: 50%; background: #d8e0ea; }
.win__bar i:nth-child(1) { background: #ff6058; }
.win__bar i:nth-child(2) { background: #ffbd2e; }
.win__bar i:nth-child(3) { background: #28c93f; }
.win__addr { margin-left: 10px; font-size: 12px; color: var(--muted); }
.win img { width: 100%; height: auto; }

.phone {
  position: absolute;
  left: -26px;
  bottom: 0;
  width: 176px;
  height: 348px;
  border: 9px solid #101d2c;
  border-radius: 30px;
  background: #101d2c;
  box-shadow: 0 24px 50px rgba(6, 26, 56, .34);
  overflow: hidden;
}
.phone__notch {
  position: absolute;
  top: 7px; left: 50%;
  transform: translateX(-50%);
  width: 58px; height: 6px;
  border-radius: 999px;
  background: #22364d;
  z-index: 2;
}
.phone img { width: 100%; height: 100%; object-fit: cover; object-position: top center; }

.badge-float {
  position: absolute;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, .96);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-m);
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-2);
  animation: float 5.5s ease-in-out infinite;
}
.badge-float--a { top: 14%; right: -18px; }
.badge-float--b { bottom: 22%; right: -10px; animation-delay: -2.6s; }
@keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-9px); } }

/* ---------------------------------------------------------------- 区块 */
.sec { padding: 92px 0; }
.sec--tint { background: var(--tint); }
.sec__head { max-width: 720px; margin: 0 auto 46px; text-align: center; }
.eyebrow {
  display: inline-block;
  margin-bottom: 12px;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--blue-600);
}
.eyebrow--orange { color: var(--orange); }
.sec__head h2, .duo__copy h2 { font-size: clamp(26px, 3vw, 36px); font-weight: 800; }
.sec__sub { margin-top: 14px; color: var(--muted); font-size: 16px; }

/* ---------------------------------------------------------------- 功能网格 */
.feat-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 20px; }
.feat {
  padding: 24px 22px 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow-s);
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}
.feat:hover { transform: translateY(-4px); box-shadow: var(--shadow-m); border-color: #cfe1fa; }
.feat h3 { display: flex; align-items: center; gap: 8px; margin-bottom: 10px; font-size: 17.5px; font-weight: 750; }
.feat p { font-size: 14.5px; color: var(--muted); }
.feat__ico {
  width: 46px; height: 46px;
  display: grid; place-items: center;
  margin-bottom: 16px;
  border-radius: 14px;
}
.feat__ico svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.feat__ico--blue   { background: #e8f1ff; color: #1677ff; }
.feat__ico--orange { background: #fff0e4; color: #ef7a2a; }
.feat__ico--pink   { background: #ffe9f1; color: #e5457f; }
.feat__ico--teal   { background: #e2f6f5; color: #109c96; }
.feat__ico--indigo { background: #ebecff; color: #5561e6; }
.feat__ico--green  { background: #e7f7ec; color: #159c4a; }
.feat__ico--rose   { background: #ffeaea; color: #e05656; }
.feat__ico--violet { background: #f1ebff; color: #7a4de0; }

.tag {
  padding: 2px 8px;
  border-radius: 6px;
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: .02em;
}
.tag--t { background: var(--blue-100); color: var(--blue-700); }
.tag--s { background: #fff1e3; color: #c96a1c; }

/* ---------------------------------------------------------------- 标签页 + 截图墙 */
.tabs {
  position: relative;
  display: flex;
  width: fit-content;
  gap: 4px;
  margin: 0 auto 30px;
  padding: 5px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  box-shadow: var(--shadow-s);
}
.tab {
  position: relative;
  z-index: 2;
  padding: 9px 26px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  font: inherit;
  font-size: 15px;
  font-weight: 650;
  color: var(--muted);
  cursor: pointer;
  transition: color .2s ease;
}
.tab.is-active { color: #fff; }
.tabs__glider {
  position: absolute;
  top: 5px; left: 5px;
  height: calc(100% - 10px);
  border-radius: 999px;
  background: linear-gradient(135deg, var(--blue-600), var(--blue-500));
  box-shadow: 0 6px 16px rgba(22, 119, 255, .30);
  transition: transform .28s cubic-bezier(.4, 0, .2, 1), width .28s cubic-bezier(.4, 0, .2, 1);
  z-index: 1;
}

.shots { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; }
.shot {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow-s);
  overflow: hidden;
  cursor: zoom-in;
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}
.shot:hover { transform: translateY(-4px); box-shadow: var(--shadow-m); border-color: #cfe1fa; }
.shot__media { position: relative; aspect-ratio: 3 / 2; background: var(--blue-50); overflow: hidden; }
.shot__media img { width: 100%; height: 100%; object-fit: cover; object-position: top center; transition: transform .5s ease; }
.shot:hover .shot__media img { transform: scale(1.035); }
.shot__zoom {
  position: absolute;
  right: 12px; bottom: 12px;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 11px;
  border-radius: 999px;
  background: rgba(13, 27, 42, .62);
  color: #fff;
  font-size: 12px;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity .2s ease, transform .2s ease;
}
.shot:hover .shot__zoom { opacity: 1; transform: none; }
.shot figcaption { padding: 16px 18px 18px; }
.shot figcaption b { display: block; font-size: 15.5px; }
.shot figcaption span { display: block; margin-top: 4px; font-size: 13.5px; color: var(--muted); }

/* ---------------------------------------------------------------- 双栏 */
.duo { display: grid; grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr); gap: 54px; align-items: center; }
.duo--reverse .duo__copy { order: 2; }
.duo--reverse .duo__shot { order: 1; }
.duo__copy p { margin-top: 16px; color: var(--muted); }
.duo__copy .btn { margin-top: 24px; }
.ticks { margin: 20px 0 0; padding: 0; list-style: none; display: grid; gap: 10px; }
.ticks li { position: relative; padding-left: 28px; font-size: 15px; color: var(--ink-2); }
.ticks li::before {
  content: "";
  position: absolute;
  left: 0; top: .48em;
  width: 17px; height: 17px;
  border-radius: 50%;
  background: var(--blue-100) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%231677ff' stroke-width='3.4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m5 13 4 4 10-10'/%3E%3C/svg%3E") center / 11px no-repeat;
}
.duo__shot { margin: 0; }
.duo__shot img {
  width: 100%;
  max-height: 560px;
  object-fit: cover;
  object-position: top center;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-m);
}
.duo__shot figcaption { margin-top: 12px; font-size: 13.5px; color: var(--muted); text-align: center; }

/* ---------------------------------------------------------------- 更新日志卡 */
.rel {
  max-width: 800px;
  margin: 0 auto;
  padding: 30px 32px 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, #fff, var(--blue-50));
  box-shadow: var(--shadow-m);
}
.rel__head { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.rel__ver { font-size: 27px; font-weight: 800; color: var(--blue-700); font-variant-numeric: tabular-nums; }
.rel__code { margin-left: 10px; font-size: 13.5px; color: var(--muted); }
.rel__code b { font-variant-numeric: tabular-nums; color: var(--ink-2); }
.rel__state {
  padding: 5px 13px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--line);
  font-size: 12.5px;
  font-weight: 600;
  color: var(--muted);
}
.rel__state.is-ok { color: #13803f; border-color: #bce6cb; background: #f0fbf3; }
.rel__state.is-fallback { color: #a6620f; border-color: #f4ddb8; background: #fff8ec; }
.rel__log {
  margin-top: 18px;
  padding: 15px 18px;
  border-radius: var(--radius-sm);
  background: #fff;
  border: 1px solid var(--line);
  font-size: 14.5px;
  color: var(--ink-2);
  white-space: pre-wrap;
  word-break: break-word;
}
.rel__actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 22px; }
.rel__url { margin-top: 16px; font-size: 12.5px; color: var(--muted); word-break: break-all; }
.rel__url a { color: var(--blue-600); text-decoration: underline; text-underline-offset: 3px; }

/* ---------------------------------------------------------------- 下载区 */
.cta {
  padding: 62px 0;
  background: linear-gradient(120deg, var(--blue-700), var(--blue-600) 48%, var(--blue-500));
  color: #fff;
}
.cta__inner { display: flex; align-items: center; justify-content: space-between; gap: 34px; flex-wrap: wrap; }
.cta h2 { font-size: clamp(24px, 2.6vw, 32px); font-weight: 800; }
.cta p { margin-top: 12px; max-width: 34em; color: rgba(255, 255, 255, .86); }

/* ---------------------------------------------------------------- 页脚 */
.foot { padding: 46px 0 54px; background: #0f1c2b; color: rgba(255, 255, 255, .74); }
.foot__inner { display: grid; grid-template-columns: 1.1fr auto; gap: 26px 40px; align-items: start; }
.foot__brand img { height: 30px; width: auto; filter: brightness(0) invert(1); opacity: .95; }
.foot__brand p { margin-top: 12px; font-size: 13.5px; }
.foot__nav { display: flex; flex-wrap: wrap; gap: 8px 22px; font-size: 14px; }
.foot__nav a:hover { color: #fff; }
.foot__note { grid-column: 1 / -1; padding-top: 20px; border-top: 1px solid rgba(255, 255, 255, .12); font-size: 12.5px; color: rgba(255, 255, 255, .52); }

/* ---------------------------------------------------------------- 灯箱 */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  padding: 40px 68px;
  background: rgba(8, 18, 32, .88);
  backdrop-filter: blur(6px);
  animation: fade .18s ease;
}
.lightbox[hidden] { display: none; }
@keyframes fade { from { opacity: 0; } to { opacity: 1; } }
.lightbox__body { margin: 0; max-width: min(1240px, 100%); max-height: 100%; display: flex; flex-direction: column; gap: 14px; }
.lightbox__body img {
  max-width: 100%;
  max-height: calc(100vh - 150px);
  object-fit: contain;
  border-radius: 12px;
  background: #fff;
  box-shadow: 0 30px 80px rgba(0, 0, 0, .5);
}
.lightbox__body figcaption { color: rgba(255, 255, 255, .86); font-size: 14.5px; text-align: center; }
.lightbox__close, .lightbox__nav {
  position: absolute;
  border: 0;
  background: rgba(255, 255, 255, .12);
  color: #fff;
  cursor: pointer;
  border-radius: 50%;
  display: grid;
  place-items: center;
  transition: background-color .2s ease;
}
.lightbox__close:hover, .lightbox__nav:hover { background: rgba(255, 255, 255, .26); }
.lightbox__close { top: 22px; right: 24px; width: 42px; height: 42px; font-size: 26px; line-height: 1; }
.lightbox__nav { top: 50%; transform: translateY(-50%); width: 46px; height: 46px; font-size: 30px; line-height: 1; }
.lightbox__nav--prev { left: 16px; }
.lightbox__nav--next { right: 16px; }

/* ---------------------------------------------------------------- 入场动画 */
[data-reveal] { opacity: 0; transform: translateY(20px); transition: opacity .6s ease, transform .6s cubic-bezier(.2, .7, .3, 1); }
[data-reveal].is-in { opacity: 1; transform: none; }

/* ---------------------------------------------------------------- 响应式 */
@media (max-width: 1080px) {
  .hero__inner { grid-template-columns: 1fr; gap: 46px; }
  .hero__stage { max-width: 640px; }
  .feat-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .shots { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .duo { grid-template-columns: 1fr; gap: 34px; }
  .duo--reverse .duo__copy, .duo--reverse .duo__shot { order: initial; }
}

@media (max-width: 820px) {
  .nav__links {
    position: absolute;
    top: var(--nav-h);
    left: 12px; right: 12px;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 10px;
    border: 1px solid var(--line);
    border-radius: 16px;
    background: #fff;
    box-shadow: var(--shadow-m);
    display: none;
  }
  .nav__links.is-open { display: flex; }
  .nav__burger {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 4px;
    width: 40px; height: 40px;
    padding: 0 9px;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: #fff;
    cursor: pointer;
  }
  .nav__burger span { height: 2px; border-radius: 2px; background: var(--ink-2); transition: transform .2s ease, opacity .2s ease; }
  .ver-chip { display: none; }
  .sec { padding: 68px 0; }
  .hero { padding-top: calc(var(--nav-h) + 40px); }
  .phone { left: -10px; width: 132px; height: 262px; border-width: 7px; border-radius: 24px; }
  .badge-float { display: none; }
  .cta__inner { flex-direction: column; align-items: flex-start; }
  .foot__inner { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .feat-grid, .shots { grid-template-columns: 1fr; }
  .hero__facts { gap: 14px 26px; }
  .lightbox { padding: 26px 14px; }
  .lightbox__nav { width: 38px; height: 38px; top: auto; bottom: 18px; transform: none; }
  .lightbox__nav--prev { left: 22%; }
  .lightbox__nav--next { right: 22%; }
  .rel { padding: 24px 20px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; transition-duration: .001ms !important; }
  [data-reveal] { opacity: 1; transform: none; }
}