:root {
    --bg: #f6fbff;
    --ink: #142033;
    --muted: #607086;
    --surface: #ffffff;
    --soft: #eaf4ff;
    --line: rgba(35, 70, 105, .13);
    --brand: #0c8a9b;
    --accent: #14b86a;
    --accent-2: #ffc44d;
    --shadow: 0 24px 70px rgba(25, 84, 126, .16);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.68;
}
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; height: auto; }
.app-head {
    position: sticky;
    top: 0;
    z-index: 30;
    min-height: 66px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 clamp(16px, 4vw, 56px);
    background: rgba(246,251,255,.9);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(18px);
}
.brand {
    min-width: 112px;
    min-height: 42px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    background: var(--ink);
    color: #fff;
    font-size: 20px;
    font-weight: 950;
}
nav { display: flex; gap: 24px; color: var(--muted); font-size: 14px; font-weight: 900; }
.app-hero {
    display: grid;
    grid-template-columns: minmax(0, .9fr) minmax(410px, 1.1fr);
    gap: clamp(26px, 5vw, 68px);
    align-items: center;
    min-height: calc(100svh - 66px);
    padding: clamp(38px, 7vw, 92px) clamp(16px, 4vw, 56px);
}
.big-logo {
    width: clamp(118px, 20vw, 210px);
    height: clamp(118px, 20vw, 210px);
    display: grid;
    place-items: center;
    margin-bottom: 24px;
    border-radius: 26px;
    background: var(--ink);
    color: #fff;
    box-shadow: var(--shadow);
    font-size: clamp(44px, 8vw, 88px);
    font-weight: 950;
}
.eyebrow {
    margin: 0 0 12px;
    color: var(--brand);
    font-size: 12px;
    font-weight: 950;
    letter-spacing: .08em;
    text-transform: uppercase;
}
h1, h2, h3, p { margin-top: 0; }
h1 { font-size: clamp(34px, 5vw, 62px); line-height: 1.08; margin-bottom: 16px; }
h2 { font-size: clamp(28px, 4vw, 46px); line-height: 1.14; margin-bottom: 14px; }
p { color: var(--muted); }
.hero-copy p { max-width: 620px; font-size: 18px; }
.actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 28px; }
.btn {
    min-width: 158px;
    min-height: 54px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0 24px;
    border-radius: 8px;
    font-size: 17px;
    font-weight: 950;
}
.btn.primary { background: var(--accent); color: #fff; }
.btn.secondary { background: var(--ink); color: #fff; }
.phone-stage img, .image-copy img, .faq img {
    width: 100%;
    aspect-ratio: 16 / 9;
    object-fit: cover;
    border-radius: 8px;
    box-shadow: var(--shadow);
}
.install-strip {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
    padding: 0 clamp(16px, 4vw, 56px) clamp(42px, 7vw, 86px);
}
.install-strip a {
    min-height: 96px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    border-radius: 8px;
    background: var(--surface);
    border: 1px solid var(--line);
    box-shadow: 0 10px 30px rgba(25, 84, 126, .08);
}
.install-strip span { color: var(--muted); font-size: 13px; font-weight: 900; }
.install-strip b { font-size: 24px; }
.intro-grid {
    display: grid;
    grid-template-columns: 1.2fr repeat(3, 1fr);
    gap: 14px;
    padding: clamp(46px, 7vw, 96px) clamp(16px, 4vw, 56px);
    background: var(--surface);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}
.intro-copy, .intro-grid article {
    padding: 24px;
    border-radius: 8px;
}
.intro-grid article {
    background: var(--soft);
    border: 1px solid var(--line);
}
.image-copy, .faq {
    display: grid;
    grid-template-columns: minmax(410px, 1.06fr) minmax(0, .94fr);
    gap: clamp(24px, 5vw, 64px);
    align-items: center;
    padding: clamp(48px, 8vw, 104px) clamp(16px, 4vw, 56px);
}
.mini-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-top: 24px;
}
.mini-list span {
    min-height: 48px;
    display: inline-flex;
    align-items: center;
    padding: 0 16px;
    border-radius: 8px;
    background: var(--surface);
    border: 1px solid var(--line);
    font-weight: 900;
}
.steps {
    padding: clamp(48px, 8vw, 104px) clamp(16px, 4vw, 56px);
    background: #eff8f8;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}
.article-band {
    padding: clamp(48px, 8vw, 104px) clamp(16px, 4vw, 56px);
    background: var(--surface);
    border-bottom: 1px solid var(--line);
}
.article-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
}
.article-grid article {
    padding: 24px;
    border-radius: 8px;
    background: var(--soft);
    border: 1px solid var(--line);
}
.article-grid p { margin-bottom: 0; }
.section-title { max-width: 760px; margin-bottom: 26px; }
.steps ol {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
    margin: 0;
    padding: 0;
    list-style: none;
    counter-reset: item;
}
.steps li {
    counter-increment: item;
    min-height: 190px;
    padding: 24px;
    border-radius: 8px;
    background: var(--surface);
    border: 1px solid var(--line);
}
.steps li::before {
    content: "0" counter(item);
    display: inline-flex;
    margin-bottom: 16px;
    color: var(--brand);
    font-size: 14px;
    font-weight: 950;
}
.steps strong { display: block; font-size: 22px; }
.steps p { margin: 8px 0 0; }
.faq article {
    margin-top: 16px;
    padding: 18px;
    border-radius: 8px;
    background: var(--surface);
    border: 1px solid var(--line);
}
.faq article p { margin-bottom: 0; }
@media (max-width: 980px) {
    nav { display: none; }
    .app-hero, .image-copy, .faq, .intro-grid { grid-template-columns: 1fr; }
    .install-strip, .steps ol, .article-grid { grid-template-columns: 1fr; }
    .app-hero { min-height: auto; }
}
@media (max-width: 560px) {
    .brand { min-width: 92px; font-size: 18px; }
    .big-logo { border-radius: 18px; }
    .actions .btn { width: 100%; }
    .install-strip a { min-height: 78px; }
    .mini-list { grid-template-columns: 1fr; }
}