/* ========== 全局重置与基础样式 ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-size: 16px;
    color: #03234b;
    font-family:  "Microsoft YaHei",  sans-serif;
    line-height: 1.6;
    background-color: #fff;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s;
}

ul, ol {
    list-style: none;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ========== 通用按钮样式 ========== */
.btn {
    padding: 12px 28px;
    border: none;
    border-radius: 4px;
    font-size: 18px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

.btn:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.btn-yellow {
    background: #FFD200;
    color: #333;
}

.btn-blue {
    background: #3CB4E6;
    color: #fff;
}

.btn-dark-blue {
    background: #0063af;
    color: #fff;
}
.btn-registered{background: #e6007e;border-radius: 8px;color: #fff;position: fixed;right: 10px;bottom: 30%;width: 90px;text-align: center;text-align: center;}
.btn-registered a{display: block;padding: 8px;}
.btn-registered img{display: inline-block; margin:2px 0;width: 40px;}
.btn-outline {
    background: #1d395d;
    color: #fff;
    border: 1px solid #4a617e;
}

.btn-full {
    width: 100%;
}

/* ========== 顶部导航 ========== */
.header {
    background: #fff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 0 20px;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
    max-width: 1200px;
    margin: 0 auto;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo-area img {
    height:auto;
}

.nav {
    display: flex;
    gap: 30px;
}

.nav a {    
   
    white-space: nowrap;
}

.nav a:hover {
    color: #3CB4E6;
}

.btn-login {
    background: #3CB4E6;
    color: #fff;
}

/* ========== 首屏Banner ========== */
.hero-banner {
    margin-top: 70px;
    background: #03234b;
    position: relative;
    overflow: hidden;
    padding: 80px 0;
}

.hero-content {
    position: relative;
    z-index: 2;
    color: #fff;
}

.hero-title {
    font-size: 54px;
    font-weight: bold;
    line-height: 1.4;
    margin-bottom: 20px;
}

.highlight {
    color: #3CB4E6;
}
.highlight:hover{text-decoration: underline;}
.hero-subtitle {
    font-size: 22px;
    color: #fff;
    margin-bottom: 30px;
}

.hero-btns {
    display: flex;
    gap: 15px;
}

.hero-bg-image {
    position: absolute;
    right: 0;
    top: 0;
    bottom: 0;
    width: 50%;
    opacityacity: 0.3;
}

.hero-bg-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* ========== 核心优势 ========== */
.advantages {
    padding: 60px 0;
    background: #f5f7fa;
}

.section-desc {
    text-align: center; 
    margin-bottom: 30px;
}
.section-desc-b{
    text-align: center; 
    margin-bottom: 00px;
    margin-top: 30px;
}
.advantage-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.advantage-card {
    background: #fff;
    padding: 30px 30px;
    border-radius: 8px;
    text-align: left;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
    transition: transform 0.3s;
}

.advantage-card:hover {
    transform: translateY(-5px);
}

.card-title {
    font-size: 22px;   
    margin-bottom: 10px;
    font-weight: bold;
}

.card-text {    
    
    font-size: 15px;
    
}

/* ========== NUCLEO产品介绍 ========== */
.product-intro {
    padding: 60px 0;
    background: #fff;
}

.tag {
    display: block;
    background: #e8f4fd;
    color: #3CB4E6;
    padding: 4px 16px;
    border-radius: 20px;    
    margin: 0 auto;
    margin-bottom: 15px;
    width: 140px;text-align: center;font-weight: bold;
}

.section-title {
    text-align: center;
    font-size: 42px;
    margin-bottom:50px;
    font-weight: bold;
}

.section-title.white {
    color: #fff;
}

.product-desc {
    margin-bottom: 20px;
}

.product-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 40px;
    margin-bottom: 50px;
}

.product-img-wrap {
    text-align: center;
}

.product-img-wrap img {
    border-radius: 8px;
    max-width: 100%;
    border: 2px solid #ccedfa;
}

.product-details h4 {    
    margin-bottom: 15px;
}

.feature-list {   
    color: #03234b;
    
}

.feature-list li{   
    position: relative;
    padding-left: 20px;
}
.feature-list li::before {
      content: "•";
    position: absolute;
    left: 0;
    color: #3CB4E6;
    font-weight: bold;
    width: 0.375rem;
    height: 0.375rem;   
}
.sub-list {
    margin-left: 15px;
    margin-top: 5px;
}

.sub-list li {
    margin-left: 0px;   
}

.tech-links {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 20px;
    background: #f5f7fa;
    border-radius: 8px;
    flex-wrap: wrap;
}

.links-label {
    font-weight: bold;   
}

.link-item {
    color: #3CB4E6;   
}

.link-item:hover {
    text-decoration: underline;
}

.link-more {
    color: #3CB4E6;
    margin-left: auto;
    border: 2px solid #3CB4E6;
    background: #fff;
    border-radius: 4px;padding: 8px 20px;
}
.link-more:hover{
   background: #3CB4E6;
   color: #fff;
   text-decoration: none;
}

/* ========== CubeMX工具介绍 ========== */
.tool-intro {
    padding: 0px 0 50px;
    background: #fff;
}

.tool-box {
    background: #fff;
    padding: 30px 40px;
    border-radius: 8px;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.1);
}

.tool-box p {
    color: #03234b;
    margin-bottom: 20px;    
}
.tool-box .btn{
    display: inline-block;margin: 20px auto 0;
}

.feature-light li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 6px;
}

.feature-light li::before {
    content: "•";
    position: absolute;
    left: 0;
    color: #3CB4E6;
    font-weight: bold;
}

/* ========== 试用活动时间轴 ========== */
.timeline-section {
    padding: 60px 0;
    background: #f5f7fa;
}

.timeline-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-bottom: 40px;
    margin-top: 100px;
}

.timeline-card {
    background: #fff;
    padding: 20px 20px;
    border-radius: 8px;   
    position: relative;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    transition: all 0.3s
}
.timeline-card:hover{
  transform: translateY(-6px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
  }
.step-num {
    width: 50px;
    height: 50px;
    background: #fff;
    color: #3CB4E6;
    border: 3px solid #3CB4E6;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    font-weight: bold;
    position: absolute;
    top: -60px;
    left: 50%;
    margin-left: -25px;
    
}
.step-time{display: flex;gap: 10px; margin-bottom: 10px;}
.step-tag {
    display: inline-block;
    background: #e8f4fd;
    color: #3CB4E6;
    padding: 4px 12px;
    border-radius: 12px;   
}

.step-title {
    font-size: 20px;
    color: #333;
    margin-bottom: 10px;
}

.step-date {
    font-size: 22px;
    color: #3CB4E6;
    font-weight: bold;   
}

.step-list {    
    color: #03234b;
    line-height:1.8;
    text-align: left;
}

.step-list li::before {
    content: "• ";
    color: #3CB4E6;
    position: absolute;left: 0;
}
.step-list li{padding-left: 15px;position: relative;}
.step-list li.highlight {
    color: #3CB4E6;
    font-weight: bold;
}

.qr-wrap {
    text-align: center;   
}

.qr-wrap img {
    width: 110px;   
    margin: 0 auto;
}
.bg-surface{padding:10px 10px;background: #f5f7fa;margin-top: 10px;}
.bitems-center{background: #fff;padding: 0.4rem 0.8rem;    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);border-radius: 4px;display: inline-block; margin: 6px 6px 0 0; }
.bitems-center:hover{color: #3CB4E6;}

/* ========== 申领区域 ========== */
.apply-section {
    padding: 60px 0;
    background: #3CB4E6;
}

.apply-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
    margin-bottom: 40px;
}

.apply-card {
    background: #fff;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    transition: all 0.3s;
}
.apply-card:hover{
  transform: translateY(-6px);
  cursor: pointer;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}
.card-highlighted {
    border: 3px solid #FFD200;
}

.card-header-yellow {
    background: #FFD200;
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.card-header-blue {
    background: #0063af;
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.mode-badge {
    background: rgba(255, 255, 255, 0.3);
    color: #fff;
    padding: 4px 12px;
    border-radius: 12px;   
}

.card-header-yellow h3,
.card-header-blue h3 {
    color: #fff;
    font-size: 22px;
    margin: 0;
}
.card-header-yellow h3 ,.card-header-yellow .mode-badge{
    color: #03234b;
}


.card-body {
    padding:20px 30px;
}

.price-box {
    margin-bottom: 10px;
}

.price-num {
    font-size: 36px;
    color: #333;
    font-weight: bold;
}

.price-label {
    
    color: #999;
    margin-left: 10px;
}

.price-desc {    
    color: #03234b;
    margin-bottom: 10px;   
    min-height: 52px;
}

.process-steps {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    background: #f5f7fa;
    padding: 15px;border-radius: 8px;
}

.p-step {
    text-align: center;
}

.circle {
    width: 40px;
    height: 40px;
    background: #3CB4E6;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 8px;
    font-size: 14px;
    font-weight: bold;
}

.circle-done {
    background: #49B170;
}

.p-step p {
    font-size: 15px;
    color: #03234b;
}

.p-line {
    width: 40px;
    height: 2px;
    background: #ddd;
    margin: 0 10px;
}

.step-done .circle {
    background: #49B170;
}

.benefit-list {
    margin-bottom: 25px;
}

.benefit-item {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin-bottom: 15px;
    font-size: 15px;    
    min-height: 48px;
}

.benefit-item .icon {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    font-weight: bold;
}

.icon-check {
    background: #d4edda;
    color: #49b170;
}

.icon-cross {
    background: #f8d7da;
    color: #dc3545;
}

.ben-ok .icon {
    background: #d4edda;
    color: #49b170;
}

.ben-no .icon {
    background: #f8d7da;
    color: #dc3545;
}

.notice-tip {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    padding: 15px;
    background: #fff3cd;
    border-radius: 4px;
    margin-bottom: 20px;
    font-size: 13px;
    color: #856404;
}

.icon-warn {
    font-size: 16px;
    font-weight: bold;
    flex-shrink: 0;
}

/* ========== 评测要求 ========== */
.requirements-section {
    padding: 60px 0;
    background: #f5f7fa;
}

.req-period {
    text-align: center;
    color: #03234b;   
    margin-bottom: 40px;
    margin-top: -40px;
}

.req-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 25px;
}

.req-card {
    background: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    border-top: 4px solid #3CB4E6;
    transition: all 0.3s;
}
.req-card:hover{
  transform: translateY(-6px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}
.req-full {
    grid-column: 1 / -1;
}
.req-card a{color: #3CB4E6;}
.req-card a:hover{text-decoration: underline;}
.req-card h3 {
    font-size: 22px;
    color: #333;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid #e8f4fd;
}

.req-card-frist{
   background: #3CB4E6; 
   color: #fff;   
}
.req-card-frist h3{color: #fff;}



/* ========== 奖励区域 ========== */
.reward-section {
    padding: 60px 0;
    background: #3b99d1;
}

.reward-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
}

.reward-card {
    background: #fff;
    padding: 30px 25px;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s;
    border-top: 4px solid #c8a456;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.reward-card:hover {
    transform: translateY(-5px);
    border-color: #c8a456;
}


.reward-card h3 {
    font-size: 22px;   
   text-align: left;
}

.reward-amt {
    font-size: 28px;
    color: #c8a456;
    font-weight: bold;
}

.reward-desc {    
    color: #999;
    margin-bottom: 10px;
    text-align: left;
}
.reward-l{text-align: left;}
/* ========== 评测视频 ========== */
.video-section {
    padding: 60px 0;
    background: #fff;
}

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

.view-more {
    color: #3CB4E6;
    font-size: 14px;
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}
.video-card{transition: transform 0.3s;}
.video-card:hover{transform: translateY(-5px);}
.video-card h4 {   
    margin-bottom: 8px;
    line-height: 1.4;
}

.author {
    font-size: 13px;
    color: #999;
}

.video-thumb {
    margin-bottom: 15px;
    border-radius: 8px;
    overflow: hidden;
    position: relative;
}
.video-thumb::after {
    content: "";
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0px;
    left: 0px;
    background: linear-gradient(rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 0.75) 100%);
}
.video-thumb i{background: url(../images/icon-play-n.png) no-repeat; background-size: 50px;display: block;width: 50px;height: 50px;left: 50%; top: 50%;margin-left: -25px;margin-top:-25px;position: absolute;z-index: 99;}
.video-thumb img {
    width: 100%;
    display: block;
}
.video-card:hover .video-thumb::after {background: linear-gradient(rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 0.3) 100%);}

/* ========== 页脚 ========== */
.footer {
    background: #03234b;
    padding: 30px 0;
    text-align: center;
}

.footer p {
    font-size: 16px;
    color: #999;
}

/* ========== 响应式设计 ========== */
@media (max-width: 1024px) {
    .advantage-grid,
    .timeline-grid,
    .apply-cards,
    .req-grid,
    .reward-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .product-content {
        grid-template-columns: 1fr;
    }
    
    .nav {
        display: none;
    }
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 32px;
    }
    
    .section-title {
        font-size: 24px;
    }
    
    .advantage-grid,
    .timeline-grid,
    .apply-cards,
    .req-grid,
    .reward-grid,
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-btns {
        flex-direction: column;
    }
    
    .process-steps {
        flex-wrap: wrap;
    }
    
    .p-line {
        display: none;
    }
}