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

body {
    font-family: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, sans-serif;
    color: #333;
    background: #eef2f3;
    line-height: 1.6;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 80px;
}

/* ── 导航栏 ── */
.header {
    height: 100px;
    background: #fff;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 1px 4px rgba(0,0,0,.06);
}

.header-content {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    width: 56px;
    height: 56px;
    object-fit: contain;
}

.logo-text {
    font-family: 'Inter', 'Noto Sans SC', sans-serif;
    font-size: 32px;
    font-weight: 400;
    color: #000;
}

.nav {
    display: flex;
    align-items: center;
    gap: 60px;
}

.nav-link {
    font-family: 'Noto Sans SC', sans-serif;
    font-size: 22px;
    font-weight: 700;
    color: #282626;
    text-decoration: none;
    letter-spacing: 0.66px;
    transition: color 0.25s;
}

.nav-link.active {
    color: #b0b0b0;
}

.nav-link:hover {
    color: #4a9e7a;
}

.nav-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 120px;
    height: 56px;
    background: #10100e;
    color: #fdf0e6;
    font-family: 'Noto Sans SC', sans-serif;
    font-size: 20px;
    font-weight: 700;
    text-decoration: none;
    border-radius: 40px;
    letter-spacing: 0.6px;
    transition: background 0.25s;
}

.nav-btn:hover {
    background: #2d2d29;
}

/* ── Hero ── */
.hero {
    background: linear-gradient(135deg, #d4ede3 0%, #bfddce 40%, #a8cfbd 100%);
    padding: 80px 0 60px;
}

.hero-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
}

.hero-text {
    flex: 1;
    max-width: 560px;
}

.hero-title {
    font-size: 42px;
    font-weight: 700;
    color: #1a1a1a;
    line-height: 1.35;
    margin-bottom: 24px;
}

.hero-desc {
    font-size: 20px;
    color: rgba(0,0,0,.65);
    line-height: 1.8;
    margin-bottom: 40px;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 160px;
    height: 56px;
    background: #10100e;
    color: #fdf0e6;
    font-family: 'Noto Sans SC', sans-serif;
    font-size: 20px;
    font-weight: 700;
    text-decoration: none;
    border-radius: 40px;
    transition: background 0.25s;
}

.download-btn:hover {
    background: #2d2d29;
}

.hero-phone {
    flex-shrink: 0;
}

.hero-phone .phone-img {
    width: 260px;
    height: auto;
    border-radius: 24px;
    box-shadow: 0 24px 60px rgba(0,0,0,.18);
    display: block;
}

/* ── 功能区通用 ── */
.features {
    padding: 80px 0;
    background: #eef2f3;
}

.features-alt {
    background: #e6ecee;
}

.section-header {
    text-align: center;
    margin-bottom: 56px;
}

.section-title {
    font-size: 34px;
    font-weight: 700;
    color: #1a1a1a;
    margin-bottom: 16px;
}

.section-desc {
    font-size: 20px;
    color: rgba(0,0,0,.6);
    line-height: 1.7;
    max-width: 780px;
    margin: 0 auto 8px;
}

/* 两列卡片布局 */
.feature-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: start;
}

.feature-card {
    background: #fff;
    border-radius: 20px;
    padding: 36px 36px 32px;
    box-shadow: 0 4px 24px rgba(0,0,0,.07);
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.feature-card .phone-wrap img {
    width: 100%;
    height: auto;
    border-radius: 14px;
    display: block;
}

.feature-card h3 {
    font-size: 24px;
    font-weight: 700;
    color: #1a1a1a;
}

.feature-card p {
    font-size: 17px;
    color: rgba(0,0,0,.6);
    line-height: 1.75;
}

/* ── 底部 ── */
.footer {
    background: #1a1f1e;
    padding: 56px 0 40px;
}

.site-footer {
    margin-top: 16px;
    text-align: center;
}

.site-footer p {
    font-size: 13px;
    color: rgba(255,255,255,.35);
    line-height: 1.9;
}

.site-footer a {
    color: rgba(255,255,255,.45);
    text-decoration: none;
}

.site-footer a:hover {
    color: rgba(255,255,255,.7);
    text-decoration: underline;
}

.footer-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 18px;
    text-align: center;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.footer-logo {
    width: 44px;
    height: 44px;
    object-fit: contain;
}

.footer-name {
    font-family: 'Inter', 'Noto Sans SC', sans-serif;
    font-size: 26px;
    font-weight: 400;
    color: #fff;
}

.footer-tagline {
    font-size: 16px;
    color: rgba(255,255,255,.55);
    max-width: 480px;
    line-height: 1.7;
}

.footer-copy {
    font-size: 14px;
    color: rgba(255,255,255,.3);
    margin-top: 8px;
}

/* ── 响应式 ── */
@media (max-width: 1100px) {
    .container { padding: 0 48px; }
}

@media (max-width: 860px) {
    .container { padding: 0 28px; }
    .hero-inner { flex-direction: column; text-align: center; }
    .hero-phone .phone-img { width: 200px; }
    .feature-row { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
    .header { height: 72px; }
    .logo-icon { width: 40px; height: 40px; }
    .logo-text { font-size: 24px; }
    .nav { gap: 28px; }
    .nav-link { font-size: 16px; }
    .nav-btn { width: 88px; height: 44px; font-size: 16px; }
    .hero { padding: 48px 0 40px; }
    .hero-title { font-size: 28px; }
    .hero-desc { font-size: 16px; }
    .features { padding: 52px 0; }
    .section-title { font-size: 26px; }
    .section-desc { font-size: 16px; }
}