/* =========================================
   1. 局部子导航
   ========================================= */
.local-subnav {
    position: sticky;
    top: 44px;
    width: 100%;
    background: rgba(29, 29, 31, 0.85); /* 深色子导航，搭配本页基调 */
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid #333;
    z-index: 1000;
    transition: background 0.3s;
}

.subnav-container {
    max-width: 980px;
    margin: 0 auto;
    padding: 0 22px;
    height: 52px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.subnav-title {
    font-size: 21px;
    font-weight: 600;
    color: #f5f5f7;
    margin: 0;
}

.subnav-links {
    list-style: none;
    display: flex;
    gap: 30px;
    margin: 0;
    padding: 0;
}

.subnav-links a {
    font-size: 12px;
    color: #a1a1a6;
    text-decoration: none;
    transition: color 0.3s;
}

.subnav-links a:hover,
.subnav-links a.active {
    color: #2997ff;
}

.btn-subnav-close {
    display: none;
    font-size: 18px;
    color: #f5f5f7;
}

/* =========================================
   2. 页面首屏 (Hero)
   ========================================= */
.page-hero {
    background-color: #000;
    color: #f5f5f7;
    text-align: center;
    padding-top: 60px;
    position: relative;
    overflow: hidden;
    min-height: 85vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.hero-inner {
    z-index: 2;
    padding-bottom: 50px;
}

.hero-title {
    font-size: 80px;
    font-weight: 700;
    margin-bottom: 10px;
    background: linear-gradient(180deg, #ffffff 0%, #86868b 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 32px;
    color: #86868b;
    margin-bottom: 30px;
}

.hero-scroll-down {
    font-size: 17px;
    color: #2997ff;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: transform 0.3s;
}

.hero-scroll-down:hover {
    transform: translateY(5px);
}

.hero-visual {
    width: 100%;
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: flex-start;
}

.hero-bg-img {
    max-width: 80%;
    max-height: 600px;
    object-fit: contain;
    opacity: 0.8;
    mix-blend-mode: screen; /* 芯片图透明背景融合 */
}

/* =========================================
   3. 通用区块样式 (Section)
   ========================================= */
.section-container {
    max-width: 980px;
    margin: 0 auto;
    padding: 120px 22px;
}

.section-header {
    text-align: center;
    margin-bottom: 80px;
}

.section-title {
    font-size: 56px;
    font-weight: 700;
    color: #f5f5f7;
    margin-bottom: 15px;
}

.section-title.text-dark {
    color: #1d1d1f;
}

.section-desc {
    font-size: 24px;
    color: #86868b;
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.4;
}

.section-desc.text-dark {
    color: #86868b;
}

.section-dark {
    background-color: #000;
}

.section-light {
    background-color: #fbfbfd;
}

/* =========================================
   4. Bento 栅格布局
   ========================================= */
.bento-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.bento-card {
    background: #161617;
    border-radius: 28px;
    padding: 40px;
    color: #f5f5f7;
    display: flex;
    flex-direction: column;
    transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.bento-card:hover {
    transform: scale(1.02);
    box-shadow: 0 20px 40px rgba(255, 255, 255, 0.05);
}

.bento-card:first-child {
    grid-column: span 2;
}

.bento-card h3 {
    font-size: 28px;
    font-weight: 600;
    margin-bottom: 12px;
}

.bento-card p {
    font-size: 17px;
    color: #a1a1a6;
    line-height: 1.5;
    margin-bottom: 30px;
}

.card-img-wrap {
    width: 100%;
    height: 300px;
    border-radius: 18px;
    overflow: hidden;
    background: #000;
    border: 1px solid #333;
}

.card-img-wrap img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.bento-card:hover .card-img-wrap img {
    transform: scale(1.05);
}

/* =========================================
   5. 左右图文交错
   ========================================= */
.content-split {
    display: flex;
    align-items: center;
    gap: 60px;
}

.split-text {
    flex: 1;
}

.split-text .section-title {
    text-align: left;
    font-size: 48px;
}

.split-text .section-desc {
    text-align: left;
    margin: 0 0 40px;
}

.split-visual {
    flex: 1;
    border-radius: 28px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0,0,0,0.1);
}

.split-visual img {
    width: 100%;
    height: auto;
    display: block;
}

.feature-list {
    list-style: none;
    padding: 0;
}

.feature-list li {
    margin-bottom: 30px;
}

.feature-list strong {
    display: block;
    font-size: 21px;
    color: #1d1d1f;
    margin-bottom: 8px;
}

.feature-list span {
    font-size: 17px;
    color: #424245;
}

/* =========================================
   6. 安全性对比条 (进度条动画)
   ========================================= */
.compare-block {
    display: flex;
    flex-direction: column;
    gap: 30px;
    max-width: 800px;
    margin: 0 auto;
}

.compare-item {
    text-align: left;
}

.compare-label {
    display: block;
    font-size: 21px;
    font-weight: 600;
    color: #f5f5f7;
    margin-bottom: 15px;
}

.progress-bar {
    height: 12px;
    background: #333;
    border-radius: 6px;
    overflow: hidden;
    margin-bottom: 15px;
}

.progress-bar .fill {
    display: block;
    height: 100%;
    border-radius: 6px;
    font-size: 10px;
    color: #fff;
    text-align: right;
    padding-right: 10px;
    line-height: 12px;
    transition: width 1.5s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.progress-bar.red .fill {
    background: linear-gradient(90deg, #ff3b30, #ff9f0a);
}

.progress-bar.green .fill {
    background: linear-gradient(90deg, #30d158, #34c759);
}

.compare-item p {
    font-size: 15px;
    color: #86868b;
}

/* =========================================
   7. 超大字引言
   ========================================= */
.text-center {
    text-align: center;
}

.quote-title {
    font-size: 64px;
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 60px;
}

.quote-title.text-dark {
    color: #1d1d1f;
}

.future-tags {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

.tag {
    padding: 12px 24px;
    border: 1px solid #424245;
    border-radius: 980px;
    color: #f5f5f7;
    font-size: 17px;
    transition: all 0.3s;
    cursor: default;
}

.tag.dark-tag {
    border-color: #d2d2d7;
    color: #1d1d1f;
    background: #fff;
}

.tag.dark-tag:hover {
    background: #1d1d1f;
    color: #fff;
    border-color: #1d1d1f;
}

/* =========================================
   8. 响应式适配
   ========================================= */
@media (max-width: 980px) {
    .hero-title { font-size: 60px; }
    .hero-subtitle { font-size: 24px; }
    .section-title { font-size: 44px; }
    .quote-title { font-size: 44px; }
    .content-split { flex-direction: column-reverse; }
    .bento-card:first-child { grid-column: span 1; }
    .bento-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .subnav-links { display: none; }
    .btn-subnav-close { display: block; }
    .page-hero { min-height: 60vh; }
    .section-container { padding: 80px 22px; }
    .section-header { margin-bottom: 50px; }
    .bento-card { padding: 30px; }
    .hero-bg-img { max-width: 100%; }
}