:root{--color:#003894;--color-dark:#002366;--color-light:#e8f0fe;--color-accent:#f7941d;--fontcolor:#111;--gray:#666;--light-gray:#f5f5f5;--border:#e0e0e0;--white:#fff;--fontfamily:'Segoe UI',Arial,Helvetica,sans-serif}
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{max-width:1920px;margin:0 auto;font-family:var(--fontfamily);font-size:16px;line-height:1.6;color:var(--fontcolor);background:var(--white)}
img{max-width:100%;height:auto;display:block}
a{color:var(--fontcolor);text-decoration:none}
a:hover{color:var(--color)}
ul,ol{list-style:none}
.container{width:100%;max-width:1400px;margin:0 auto;padding:0 20px}
.container-narrow{max-width:1200px}
.section{padding:80px 0}
.section-gray{background:var(--light-gray)}
.section-dark{background:var(--color);color:var(--white)}
.section-title{font-size:32px;font-weight:700;text-align:center;margin-bottom:15px;text-transform:capitalize}
.section-subtitle{font-size:16px;color:var(--gray);text-align:center;margin-bottom:50px;max-width:800px;margin-left:auto;margin-right:auto}
.section-dark .section-title,.section-dark .section-subtitle{color:var(--white)}
.section-dark .section-subtitle{color:rgba(255,255,255,0.8)}
.btn{display:inline-block;padding:14px 36px;font-size:16px;font-weight:600;border-radius:4px;cursor:pointer;transition:all 0.3s;text-transform:uppercase;letter-spacing:0.5px}
.btn-primary{background:var(--color-accent);color:var(--white);border:2px solid var(--color-accent)}
.btn-primary:hover{background:#e07d0a;border-color:#e07d0a;color:var(--white)}
.btn-outline{background:transparent;color:var(--color);border:2px solid var(--color)}
.btn-outline:hover{background:var(--color);color:var(--white)}
.btn-white{background:var(--white);color:var(--color);border:2px solid var(--white)}
.btn-white:hover{background:transparent;color:var(--white)}
.header{position:sticky;top:0;z-index:1000;background:var(--white);box-shadow:0 2px 10px rgba(0,0,0,0.08)}
.header-top{background:var(--color);color:var(--white);padding:8px 0;font-size:14px}
.header-top .container{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap}
.header-top a{color:var(--white)}.header-top a:hover{color:var(--color-accent)}
.header-main{padding:15px 0}
.header-main .container{display:flex;justify-content:space-between;align-items:center}
.logo{font-size:28px;font-weight:700;color:var(--color)}
.logo small{font-size:13px;font-weight:400;color:var(--gray);display:block}
.nav{display:flex;gap:30px;align-items:center}
.nav a{font-size:15px;font-weight:600;text-transform:uppercase;letter-spacing:0.5px;padding:8px 0;position:relative}
.nav a::after{content:'';position:absolute;bottom:0;left:0;width:0;height:2px;background:var(--color);transition:width 0.3s}
.nav a:hover::after{width:100%}
.header-contact{display:flex;align-items:center;gap:12px}
.header-contact .phone-icon{width:40px;height:40px;background:var(--color);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:18px;color:var(--white)}
.header-contact .phone-info p{font-size:12px;color:var(--gray)}
.header-contact .phone-info .phone{font-size:18px;font-weight:700;color:var(--color)}
.hamburger{display:none;flex-direction:column;gap:5px;cursor:pointer}
.hamburger span{width:28px;height:3px;background:var(--color);border-radius:2px;transition:all 0.3s}

.hero{background:linear-gradient(135deg,var(--color) 0%,#001a4d 100%);color:var(--white);padding:100px 0 80px;position:relative;overflow:hidden}
.hero::before{content:'';position:absolute;top:-50%;right:-20%;width:800px;height:800px;background:radial-gradient(circle,rgba(255,255,255,0.05) 0%,transparent 70%);border-radius:50%}
.hero .container{display:flex;align-items:center;gap:60px;position:relative;z-index:1}
.hero-content{flex:1}
.hero-content h1{font-size:44px;font-weight:800;line-height:1.2;margin-bottom:20px}
.hero-content h1 span{color:var(--color-accent)}
.hero-content p{font-size:18px;margin-bottom:30px;opacity:0.9;line-height:1.7;max-width:600px}
.hero-features{display:flex;gap:30px;margin-bottom:30px;flex-wrap:wrap}
.hero-features .hf-item{display:flex;align-items:center;gap:10px;font-size:15px;font-weight:600}
.hero-features .hf-icon{width:36px;height:36px;background:rgba(255,255,255,0.15);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:16px}
.hero-image{flex:1;text-align:center}
.hero-image img{max-height:450px;margin:0 auto;border-radius:12px;box-shadow:0 20px 60px rgba(0,0,0,0.3)}
.about-grid{display:grid;grid-template-columns:1fr 1fr;gap:60px;align-items:center}
.about-img img{border-radius:12px;box-shadow:0 10px 40px rgba(0,0,0,0.1)}
.about-text .about-tag{color:var(--color);font-weight:600;text-transform:uppercase;letter-spacing:2px;margin-bottom:10px;font-size:14px}
.about-text h2{font-size:36px;margin-bottom:15px}
.about-text p{margin-bottom:15px;color:#444;line-height:1.8}
.about-highlight{background:var(--color-light);border-left:4px solid var(--color);padding:15px 20px;margin:20px 0;font-weight:600}
.about-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:60px}
.about-stat{text-align:center;padding:30px 20px;background:var(--white);border-radius:8px;box-shadow:0 5px 20px rgba(0,0,0,0.05);transition:transform 0.3s}
.about-stat:hover{transform:translateY(-5px)}
.about-stat .stat-num{font-size:40px;font-weight:800;color:var(--color)}
.about-stat .stat-label{font-size:14px;color:var(--gray);margin-top:5px}

.principle-grid{display:grid;grid-template-columns:1fr 1fr;gap:60px;align-items:center}
.principle-steps{display:flex;flex-direction:column;gap:20px}
.principle-step{display:flex;gap:20px;align-items:flex-start}
.principle-step .step-num{width:50px;height:50px;min-width:50px;background:var(--color);color:var(--white);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:22px;font-weight:700}
.principle-step h4{font-size:18px;margin-bottom:5px}
.principle-step p{color:#555;font-size:14px}
.principle-img img{border-radius:12px;box-shadow:0 10px 40px rgba(0,0,0,0.1)}
.specs-table-wrap{overflow-x:auto;margin-top:30px}
.specs-table{width:100%;border-collapse:collapse;box-shadow:0 5px 20px rgba(0,0,0,0.05);border-radius:8px;overflow:hidden;min-width:850px}
.specs-table thead{background:var(--color);color:var(--white)}
.specs-table th{padding:16px;text-align:center;font-weight:600;font-size:15px}
.specs-table th:first-child{text-align:left}
.specs-table td{padding:14px 16px;border-bottom:1px solid var(--border);font-size:14px;text-align:center}
.specs-table td:first-child{text-align:left;font-weight:600}
.specs-table tbody tr:hover{background:var(--color-light)}
.specs-table tbody tr:nth-child(even){background:#fafafa}
.spec-highlight{text-align:center;margin:40px 0;padding:25px;background:var(--color);color:var(--white);border-radius:8px;font-size:20px;font-weight:600}
.materials-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:25px}
.material-card{background:var(--white);border-radius:10px;overflow:hidden;box-shadow:0 5px 20px rgba(0,0,0,0.08);transition:all 0.3s;text-align:center}
.material-card:hover{transform:translateY(-8px);box-shadow:0 15px 40px rgba(0,0,0,0.15)}
.material-card .mat-img{height:200px;overflow:hidden;background:#f0f0f0;display:flex;align-items:center;justify-content:center}
.material-card .mat-img img{width:100%;height:100%;object-fit:cover}
.material-card .mat-info{padding:20px}
.material-card .mat-info h4{font-size:18px;margin-bottom:5px;color:var(--color)}
.material-card .mat-info p{font-size:13px;color:var(--gray)}
.video-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:25px;margin-top:30px}
.video-item{border-radius:10px;overflow:hidden;box-shadow:0 5px 20px rgba(0,0,0,0.08)}
.video-item video{width:100%;display:block}
.video-item .video-caption{padding:12px 15px;background:var(--white);font-size:14px;font-weight:600;text-align:center}

.parts-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:25px;margin-top:40px}
.part-card{background:var(--white);border-radius:10px;overflow:hidden;box-shadow:0 5px 20px rgba(0,0,0,0.08);transition:all 0.3s}
.part-card:hover{transform:translateY(-5px);box-shadow:0 15px 40px rgba(0,0,0,0.15)}
.part-card .part-img{height:250px;overflow:hidden;background:#f0f0f0;display:flex;align-items:center;justify-content:center}
.part-card .part-img img{width:100%;height:100%;object-fit:cover}
.part-card .part-info{padding:20px}
.part-card .part-info h4{font-size:18px;margin-bottom:8px;color:var(--color)}
.part-card .part-material{display:inline-block;background:var(--color-accent);color:var(--white);padding:4px 12px;border-radius:20px;font-size:12px;font-weight:600;margin-bottom:10px}
.part-card .part-info p{font-size:13px;color:var(--gray)}
.comparison-wrap{overflow-x:auto;margin-top:30px}
.comparison-table{width:100%;border-collapse:collapse;box-shadow:0 5px 20px rgba(0,0,0,0.05);border-radius:8px;overflow:hidden;min-width:750px}
.comparison-table thead{background:var(--color);color:var(--white)}
.comparison-table th{padding:16px 14px;text-align:center;font-weight:600;font-size:15px}
.comparison-table th:first-child{text-align:left}
.comparison-table td{padding:14px;border-bottom:1px solid var(--border);font-size:14px;text-align:center}
.comparison-table td:first-child{text-align:left;font-weight:600}
.comparison-table tbody tr:hover{background:var(--color-light)}
.comparison-table .highlight-col{background:#e8f5e9}
.comparison-table .highlight-col:hover{background:#c8e6c9}
.comparison-table .check{color:#2e7d32;font-weight:700;font-size:18px}
.comparison-table .cross{color:#c62828}
.cases-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:25px;margin-top:40px}
.case-card{background:var(--white);border-radius:10px;overflow:hidden;box-shadow:0 5px 20px rgba(0,0,0,0.08);transition:all 0.3s}
.case-card:hover{transform:translateY(-5px);box-shadow:0 15px 40px rgba(0,0,0,0.15)}
.case-card .case-img{height:220px;overflow:hidden}
.case-card .case-img img{width:100%;height:100%;object-fit:cover}
.case-card .case-info{padding:20px}
.case-card .case-location{font-size:12px;color:var(--color-accent);font-weight:600;text-transform:uppercase}
.case-card .case-info h4{font-size:18px;margin:5px 0 10px}
.case-card .case-info p{font-size:13px;color:var(--gray)}
.faq-list{max-width:900px;margin:40px auto 0}
.faq-item{border-bottom:1px solid var(--border);padding:5px 0}
.faq-question{display:flex;justify-content:space-between;align-items:center;padding:18px 0;cursor:pointer;font-weight:600;font-size:17px}
.faq-question:hover{color:var(--color)}
.faq-question .faq-icon{font-size:24px;transition:transform 0.3s;width:30px;height:30px;display:flex;align-items:center;justify-content:center;background:var(--color-light);border-radius:50%;color:var(--color);flex-shrink:0}
.faq-item.active .faq-question .faq-icon{transform:rotate(45deg);background:var(--color);color:var(--white)}
.faq-answer{max-height:0;overflow:hidden;transition:max-height 0.3s ease,padding 0.3s ease;color:#555;line-height:1.8;font-size:15px}
.faq-item.active .faq-answer{max-height:500px;padding-bottom:20px}

.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:50px;align-items:start}
.contact-info h3{font-size:24px;margin-bottom:20px}
.contact-item{display:flex;gap:15px;margin-bottom:20px;align-items:flex-start}
.contact-item .ci-icon{width:44px;height:44px;min-width:44px;background:var(--color-light);border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:18px;color:var(--color)}
.contact-item h5{font-size:16px;margin-bottom:3px}
.contact-item p{font-size:14px;color:var(--gray)}
.contact-form{background:var(--white);padding:35px;border-radius:12px;box-shadow:0 10px 40px rgba(0,0,0,0.1)}
.contact-form h3{font-size:22px;margin-bottom:25px;text-align:center}
.form-group{margin-bottom:18px}
.form-group label{display:block;font-weight:600;margin-bottom:6px;font-size:14px}
.form-group input,.form-group textarea,.form-group select{width:100%;padding:12px 15px;border:2px solid var(--border);border-radius:6px;font-size:15px;font-family:var(--fontfamily);transition:border-color 0.3s}
.form-group input:focus,.form-group textarea:focus,.form-group select:focus{outline:none;border-color:var(--color)}
.form-group textarea{height:120px;resize:vertical}
.contact-form .btn{width:100%;text-align:center;font-size:17px;padding:16px}
.cta-banner{background:linear-gradient(135deg,var(--color-accent) 0%,#e07d0a 100%);text-align:center;padding:60px 20px}
.cta-banner h2{font-size:36px;color:var(--white);margin-bottom:15px}
.cta-banner p{font-size:18px;color:rgba(255,255,255,0.9);margin-bottom:25px}
.footer{background:#1a1a1a;color:#bbb;padding:60px 0 0}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1.5fr;gap:40px;padding-bottom:40px;border-bottom:1px solid #333}
.footer h4{color:var(--white);font-size:18px;margin-bottom:20px;text-transform:capitalize}
.footer p{font-size:14px;line-height:1.8;margin-bottom:10px}
.footer a{color:#bbb;font-size:14px;line-height:2.2;display:block}
.footer a:hover{color:var(--color-accent)}
.footer .footer-logo{font-size:24px;font-weight:700;color:var(--white);margin-bottom:15px}
.footer-social{display:flex;gap:12px;margin-top:15px}
.footer-social a{width:36px;height:36px;background:#333;border-radius:50%;display:flex;align-items:center;justify-content:center;color:var(--white);font-size:14px}
.footer-social a:hover{background:var(--color-accent);color:var(--white)}
.footer-bottom{padding:20px 0;text-align:center;font-size:13px;color:#777}
.footer-bottom a{color:#999;display:inline}
.footer-bottom a:hover{color:var(--color-accent)}
.mobile-nav{display:none;position:fixed;top:0;left:0;width:100%;height:100%;background:var(--white);z-index:2000;padding:20px;flex-direction:column;overflow-y:auto}
.mobile-nav.active{display:flex}
.mobile-nav .close-btn{align-self:flex-end;font-size:28px;cursor:pointer;padding:10px}
.mobile-nav a{font-size:18px;padding:15px 0;border-bottom:1px solid var(--border);font-weight:600}
@media(max-width:1024px){.nav,.header-contact{display:none}.hamburger{display:flex}.hero .container{flex-direction:column;text-align:center}.hero-content p{margin:0 auto 30px}.hero-features{justify-content:center}.hero-content h1{font-size:34px}.about-grid,.principle-grid{grid-template-columns:1fr}.materials-grid{grid-template-columns:repeat(2,1fr)}.parts-grid{grid-template-columns:repeat(2,1fr)}.cases-grid{grid-template-columns:repeat(2,1fr)}.video-grid{grid-template-columns:1fr}.contact-grid{grid-template-columns:1fr}.about-stats{grid-template-columns:repeat(2,1fr)}.footer-grid{grid-template-columns:1fr 1fr}.section{padding:50px 0}.section-title{font-size:26px}}
@media(max-width:640px){.materials-grid,.parts-grid,.cases-grid{grid-template-columns:1fr}.about-stats{grid-template-columns:1fr}.footer-grid{grid-template-columns:1fr}.hero-content h1{font-size:28px}.header-top{font-size:12px}.cta-banner h2{font-size:24px}.about-text h2{font-size:24px}}