:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --secondary-color: #0f172a;
    --accent-color: #06b6d4;
    --text-color: #334155;
    --text-light: #64748b;
    --text-lighter: #94a3b8;
    --bg-color: #ffffff;
    --bg-light: #f8fafc;
    --bg-dark: #0f172a;
    --border-color: #e2e8f0;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --gradient-primary: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
    --gradient-dark: linear-gradient(135deg, var(--secondary-color) 0%, #1e293b 100%);
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    --border-radius-sm: 0.375rem;
    --border-radius-md: 0.5rem;
    --border-radius-lg: 0.75rem;
    --border-radius-xl: 1rem;
    --border-radius-2xl: 1.5rem;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
}

button {
    cursor: pointer;
    border: none;
    outline: none;
    font-family: inherit;
}

input, textarea, select {
    font-family: inherit;
    font-size: inherit;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 5rem 0;
}

.section__title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 0.5rem;
    color: var(--secondary-color);
}

.section__subtitle {
    font-size: 1.125rem;
    text-align: center;
    color: var(--text-light);
    margin-bottom: 3rem;
}

.highlight {
    color: var(--primary-color);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--border-radius-lg);
    transition: all var(--transition-normal);
    cursor: pointer;
}

.btn--primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn--primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn--outline {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn--outline:hover {
    background: var(--primary-color);
    color: white;
}

.btn--small {
    padding: 0.625rem 1.25rem;
    font-size: 0.875rem;
}

.btn--block {
    width: 100%;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all var(--transition-normal);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 4.5rem;
}

.nav__logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
}

.nav__logo i {
    color: var(--primary-color);
}

.nav__list {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav__link {
    font-weight: 500;
    color: var(--text-color);
    transition: color var(--transition-fast);
    position: relative;
}

.nav__link::after {
    content: '';
    position: absolute;
    bottom: -0.25rem;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width var(--transition-normal);
}

.nav__link:hover,
.nav__link.active {
    color: var(--primary-color);
}

.nav__link:hover::after,
.nav__link.active::after {
    width: 100%;
}

.nav__toggle,
.nav__close {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--secondary-color);
}

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--bg-light) 0%, white 50%, var(--bg-light) 100%);
    padding-top: 4.5rem;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 80%;
    height: 150%;
    background: radial-gradient(circle, rgba(37, 99, 235, 0.05) 0%, transparent 70%);
    pointer-events: none;
}

.hero__container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero__title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    color: var(--secondary-color);
    margin-bottom: 1.5rem;
}

.hero__description {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: 2rem;
    max-width: 540px;
}

.hero__buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.hero__image {
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.hero__shape {
    position: absolute;
    width: 400px;
    height: 400px;
    background: var(--gradient-primary);
    border-radius: 50%;
    opacity: 0.1;
    animation: pulse 4s ease-in-out infinite;
}

.hero__image i {
    font-size: 15rem;
    color: var(--primary-color);
    position: relative;
    z-index: 1;
    animation: float 6s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        opacity: 0.1;
    }
    50% {
        transform: scale(1.1);
        opacity: 0.15;
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

.services {
    background: var(--bg-light);
}

.services__grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.service__card {
    background: white;
    padding: 2rem;
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    border: 1px solid var(--border-color);
}

.service__card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.service__icon {
    width: 4rem;
    height: 4rem;
    background: var(--gradient-primary);
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.service__icon i {
    font-size: 1.75rem;
    color: white;
}

.service__title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 0.75rem;
}

.service__description {
    color: var(--text-light);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

.service__features {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.service__features li {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-color);
}

.service__features i {
    color: var(--success-color);
    font-size: 0.75rem;
}

.products {
    background: white;
}

.products__grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-bottom: 4rem;
}

.product__card {
    background: white;
    padding: 2rem;
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.product__card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.product__card--featured {
    border: 2px solid var(--primary-color);
}

.product__badge {
    position: absolute;
    top: 1rem;
    right: -2rem;
    background: var(--gradient-primary);
    color: white;
    padding: 0.25rem 2.5rem;
    font-size: 0.75rem;
    font-weight: 600;
    transform: rotate(45deg);
}

.product__brand {
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    background: var(--bg-light);
    border-radius: var(--border-radius-md);
}

.product__logo {
    max-height: 40px;
    object-fit: contain;
}

.product__title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 0.75rem;
    text-align: center;
}

.product__description {
    color: var(--text-light);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
    text-align: center;
}

.product__features {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.product__features li {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-color);
}

.product__features i {
    color: var(--primary-color);
    width: 1rem;
}

.product__card .btn {
    width: 100%;
}

.certificate__types {
    background: var(--bg-light);
    padding: 3rem;
    border-radius: var(--border-radius-2xl);
}

.certificate__title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    text-align: center;
    margin-bottom: 2rem;
}

.certificate__grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.certificate__item {
    text-align: center;
    padding: 1.5rem;
    background: white;
    border-radius: var(--border-radius-lg);
    transition: all var(--transition-normal);
}

.certificate__item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.certificate__item i {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.certificate__item h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.certificate__item p {
    font-size: 0.875rem;
    color: var(--text-light);
}

.about {
    background: var(--bg-light);
}

.about__content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: start;
}

.about__heading {
    font-size: 2rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

.about__text {
    color: var(--text-light);
    margin-bottom: 1rem;
    line-height: 1.8;
}

.about__stats {
    display: flex;
    gap: 3rem;
    margin-top: 2rem;
}

.stat__item {
    text-align: center;
}

.stat__number {
    display: block;
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary-color);
}

.stat__label {
    display: block;
    font-size: 0.875rem;
    color: var(--text-light);
    margin-top: 0.25rem;
}

.about__features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.feature__item {
    display: flex;
    gap: 1rem;
    padding: 1.5rem;
    background: white;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

.feature__item:hover {
    box-shadow: var(--shadow-md);
    transform: translateX(4px);
}

.feature__icon {
    width: 3rem;
    height: 3rem;
    background: var(--gradient-primary);
    border-radius: var(--border-radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.feature__icon i {
    font-size: 1.25rem;
    color: white;
}

.feature__content h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 0.25rem;
}

.feature__content p {
    font-size: 0.875rem;
    color: var(--text-light);
}

.contact {
    background: white;
}

.contact__content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact__info {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.contact__card {
    background: var(--bg-light);
    padding: 1.5rem;
    border-radius: var(--border-radius-lg);
    text-align: center;
    transition: all var(--transition-normal);
}

.contact__card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.contact__card i {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 0.75rem;
}

.contact__card h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.contact__card p {
    font-size: 0.875rem;
    color: var(--text-light);
}

.contact__form {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: var(--border-radius-xl);
}

.form__group {
    margin-bottom: 1rem;
}

.form__input {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-md);
    background: white;
    color: var(--text-color);
    transition: all var(--transition-fast);
}

.form__input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form__input::placeholder {
    color: var(--text-lighter);
}

.form__textarea {
    min-height: 120px;
    resize: vertical;
}

select.form__input {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2364748b' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
}

.footer {
    background: var(--gradient-dark);
    color: white;
    padding: 4rem 0 0;
}

.footer__content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 3rem;
    padding-bottom: 3rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer__logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: white;
    margin-bottom: 1rem;
}

.footer__logo i {
    color: var(--accent-color);
}

.footer__description {
    color: var(--text-lighter);
    margin-bottom: 1.5rem;
}

.footer__social {
    display: flex;
    gap: 1rem;
}

.social__link {
    width: 2.5rem;
    height: 2.5rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-normal);
}

.social__link:hover {
    background: var(--primary-color);
    transform: translateY(-2px);
}

.social__link i {
    font-size: 1.25rem;
}

.footer__title {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: white;
}

.footer__list li {
    margin-bottom: 0.75rem;
}

.footer__list a {
    color: var(--text-lighter);
    transition: color var(--transition-fast);
}

.footer__list a:hover {
    color: var(--accent-color);
}

.footer__bottom {
    text-align: center;
    padding: 1.5rem 0;
    color: var(--text-lighter);
    font-size: 0.875rem;
}

.scrollup {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 3rem;
    height: 3rem;
    background: var(--gradient-primary);
    color: white;
    border-radius: var(--border-radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
    z-index: 999;
}

.scrollup:hover {
    transform: translateY(-4px);
}

.scrollup.show {
    opacity: 1;
    visibility: visible;
}

@media screen and (max-width: 1200px) {
    .services__grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .products__grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .certificate__grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media screen and (max-width: 992px) {
    .section {
        padding: 4rem 0;
    }
    
    .section__title {
        font-size: 2rem;
    }
    
    .hero__container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero__title {
        font-size: 2.5rem;
    }
    
    .hero__description {
        margin: 0 auto 2rem;
    }
    
    .hero__buttons {
        justify-content: center;
    }
    
    .hero__image {
        display: none;
    }
    
    .about__content {
        grid-template-columns: 1fr;
    }
    
    .about__features {
        grid-template-columns: 1fr;
    }
    
    .contact__content {
        grid-template-columns: 1fr;
    }
    
    .footer__content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media screen and (max-width: 768px) {
    .nav__menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 300px;
        height: 100vh;
        background: white;
        box-shadow: var(--shadow-xl);
        padding: 4rem 2rem;
        transition: right var(--transition-normal);
    }
    
    .nav__menu.show {
        right: 0;
    }
    
    .nav__list {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .nav__toggle,
    .nav__close {
        display: block;
    }
    
    .nav__close {
        position: absolute;
        top: 1.5rem;
        right: 1.5rem;
    }
    
    .services__grid {
        grid-template-columns: 1fr;
    }
    
    .products__grid {
        grid-template-columns: 1fr;
    }
    
    .certificate__grid {
        grid-template-columns: 1fr;
    }
    
    .about__stats {
        justify-content: center;
    }
    
    .contact__info {
        grid-template-columns: 1fr;
    }
    
    .footer__content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer__social {
        justify-content: center;
    }
}

@media screen and (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }
    
    .section {
        padding: 3rem 0;
    }
    
    .section__title {
        font-size: 1.75rem;
    }
    
    .hero__title {
        font-size: 2rem;
    }
    
    .hero__description {
        font-size: 1rem;
    }
    
    .btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.875rem;
    }
    
    .hero__buttons {
        flex-direction: column;
    }
    
    .hero__buttons .btn {
        width: 100%;
    }
    
    .about__stats {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .stat__number {
        font-size: 2rem;
    }
    
    .scrollup {
        bottom: 1rem;
        right: 1rem;
        width: 2.5rem;
        height: 2.5rem;
    }
}