/* style.css - Hunan Xintai Environmental Protection Technology Co., Ltd. */

:root {
    /* Colors - Blue Theme */
    --primary-color: #0056b3;
    --primary-dark: #003d82;
    --primary-light: #4da3ff;
    --accent-color: #00b4d8;

    /* Grays & Neutrals */
    --text-main: #333333;
    --text-muted: #666666;
    --bg-main: #ffffff;
    --bg-light: #f4f7f6;
    --border-color: #e2e8f0;

    /* Typography */
    --font-heading: 'Outfit', sans-serif;
    --font-body: 'Inter', sans-serif;

    /* Spacing & Layout */
    --container-width: 1200px;
    --section-spacing: 80px;
    --border-radius-sm: 8px;
    --border-radius-md: 12px;
    --border-radius-lg: 20px;
    --shadow-sm: 0 4px 6px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 10px 30px rgba(0, 86, 179, 0.08);
    --shadow-hover: 0 20px 40px rgba(0, 86, 179, 0.15);

    /* Transitions */
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-body);
    color: var(--text-main);
    background-color: var(--bg-main);
    line-height: 1.6;
    overflow-x: hidden;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    color: var(--primary-dark);
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

ul {
    list-style: none;
}

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

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: var(--section-spacing) 0;
}

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

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

.mt-4 {
    margin-top: 2rem;
}

.mx-auto {
    margin-left: auto;
    margin-right: auto;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 24px;
    font-family: var(--font-heading);
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: var(--transition);
    gap: 8px;
    border: 2px solid transparent;
}

.btn-lg {
    padding: 14px 32px;
    font-size: 1.1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: white;
    box-shadow: 0 4px 15px rgba(0, 180, 216, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 180, 216, 0.4);
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
}

.btn-outline {
    background: transparent;
    border-color: white;
    color: white;
}

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

/* Typography Helpers */
.section-badge {
    display: inline-block;
    padding: 6px 16px;
    background-color: rgba(0, 86, 179, 0.1);
    color: var(--primary-color);
    font-family: var(--font-heading);
    font-weight: 600;
    font-size: 0.875rem;
    border-radius: 50px;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 16px;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 24px;
}

.section-subtitle,
.section-description {
    font-size: 1.125rem;
    color: var(--text-muted);
    margin-bottom: 24px;
    max-width: 700px;
}

.text-center .section-subtitle {
    margin-left: auto;
    margin-right: auto;
}

/* Header & Navigation */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.header.scrolled {
    padding: 10px 0;
}

.header:not(.scrolled) {
    padding: 20px 0;
}

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

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

.logo-text {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    color: var(--primary-dark);
}

.logo-text strong {
    color: var(--primary-color);
}

.nav {
    display: flex;
    align-items: center;
    gap: 40px;
}

.nav-list {
    display: flex;
    gap: 32px;
}

.nav-list a {
    font-weight: 500;
    color: var(--text-main);
    position: relative;
    padding: 8px 0;
}

.nav-list a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

.nav-list a:hover::after,
.nav-list a.active::after {
    width: 100%;
}

.nav-list a:hover,
.nav-list a.active {
    color: var(--primary-color);
}

.mobile-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--primary-dark);
    cursor: pointer;
}

/* Hero Section */
.hero {
    height: 100vh;
    min-height: 600px;
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    align-items: center;
    position: relative;
    padding-top: 80px;
    color: white;
}

.hero-content {
    max-width: 800px;
    animation: fadeInUp 1s ease-out;
}

.hero .badge {
    display: inline-block;
    padding: 8px 20px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(5px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 500;
    letter-spacing: 1px;
    margin-bottom: 24px;
}

.hero-title {
    font-size: 4rem;
    color: white;
    margin-bottom: 24px;
}

.hero-title span {
    color: var(--accent-color);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-actions {
    display: flex;
    gap: 20px;
}

.hero-stats {
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translate(-50%, 50%);
    display: flex;
    background: white;
    padding: 30px 60px;
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-md);
    gap: 80px;
    z-index: 10;
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.stat-text {
    font-family: var(--font-heading);
    font-weight: 500;
    color: var(--text-muted);
}

/* About Section */
.about {
    padding-top: 140px;
    /* Account for hero-stats overlapping */
}

.about-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-image-wrapper {
    position: relative;
}

.about-image {
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    aspect-ratio: 4/3;
    background: linear-gradient(135deg, var(--bg-light), #e0f2fe);
}

.about-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: var(--primary-light);
    font-family: var(--font-heading);
    font-size: 1.5rem;
}

.about-placeholder i {
    font-size: 4rem;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.experience-badge {
    position: absolute;
    bottom: -30px;
    right: -30px;
    background: var(--primary-dark);
    color: white;
    width: 150px;
    height: 150px;
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
    border: 8px solid white;
}

.experience-badge .years {
    font-size: 2.5rem;
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1;
}

.experience-badge .text {
    font-size: 0.875rem;
    font-weight: 500;
}

.about-features {
    margin-top: 30px;
}

.about-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
    font-weight: 500;
    color: var(--primary-dark);
}

.about-features i {
    color: var(--accent-color);
    font-size: 1.25rem;
}

/* Products Section */
.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.product-card {
    background: white;
    padding: 40px 30px;
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.product-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-hover);
    border-color: rgba(0, 180, 216, 0.3);
}

.product-icon {
    width: 70px;
    height: 70px;
    background: rgba(0, 86, 179, 0.05);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.75rem;
    color: var(--primary-color);
    margin-bottom: 24px;
    transition: var(--transition);
}

.product-card:hover .product-icon {
    background: var(--primary-color);
    color: white;
}

.product-title {
    font-size: 1.25rem;
    margin-bottom: 16px;
}

.product-desc {
    color: var(--text-muted);
}

/* Why Choose Us Section */
.why-us-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 60px;
}

@media (min-width: 992px) {
    .why-us-layout {
        grid-template-columns: 3fr 2fr;
        align-items: center;
    }
}

.reasons-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.reason-item {
    display: flex;
    gap: 20px;
}

.reason-number {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 800;
    color: rgba(0, 86, 179, 0.2);
    line-height: 1;
}

.reason-text h3 {
    font-size: 1.125rem;
    margin-bottom: 8px;
}

.reason-text p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.why-us-visual {
    position: relative;
    height: 500px;
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
    border-radius: var(--border-radius-lg);
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}

.glow-circle {
    position: absolute;
    width: 300px;
    height: 300px;
    background: rgba(0, 180, 216, 0.4);
    border-radius: 50%;
    filter: blur(60px);
}

.abstract-shape {
    position: relative;
    z-index: 2;
    text-align: center;
    color: white;
}

.icon-large {
    font-size: 5rem;
    color: var(--accent-color);
    margin-bottom: 20px;
}

/* Footer Section */
.footer {
    background-color: var(--primary-dark);
    color: rgba(255, 255, 255, 0.8);
}

.footer-cta {
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    padding: 60px 0;
}

.cta-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 30px;
}

.cta-text h2 {
    color: white;
    margin-bottom: 10px;
}

.cta-text p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.125rem;
}

.cta-btn .btn-primary {
    background: white;
    color: var(--primary-dark);
}

.cta-btn .btn-primary:hover {
    background: var(--bg-light);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.footer-main {
    padding: 80px 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
}

@media (min-width: 992px) {
    .brand-col {
        grid-column: span 2;
    }
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: white;
    margin-bottom: 24px;
}

.footer-desc {
    margin-bottom: 24px;
    max-width: 350px;
}

.social-links {
    display: flex;
    gap: 16px;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
    color: white;
}

.social-links a:hover {
    background: var(--accent-color);
    transform: translateY(-3px);
}

.footer-title {
    color: white;
    font-size: 1.25rem;
    margin-bottom: 24px;
}

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a:hover {
    color: var(--accent-color);
    padding-left: 5px;
}

.contact-list li {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
}

.contact-list i {
    color: var(--accent-color);
    font-size: 1.25rem;
    margin-top: 4px;
}

.contact-list span {
    display: block;
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: rgba(255, 255, 255, 0.5);
    margin-bottom: 4px;
}

.contact-list strong {
    color: white;
    font-weight: 500;
}

.footer-bottom {
    background-color: rgba(0, 0, 0, 0.2);
    padding: 24px 0;
}

.bottom-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.legal-links {
    display: flex;
    gap: 20px;
}

.legal-links a:hover {
    color: white;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive Design */
@media (max-width: 992px) {
    .nav {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 30px;
        box-shadow: var(--shadow-md);
        gap: 20px;
    }

    .nav.active {
        display: flex;
    }

    .nav-list {
        flex-direction: column;
        align-items: center;
        gap: 20px;
        width: 100%;
    }

    .mobile-toggle {
        display: block;
    }

    .hero-stats {
        position: relative;
        flex-direction: column;
        gap: 30px;
        padding: 24px;
        transform: none;
        left: 0;
        bottom: 0;
        margin: 40px auto 0;
        width: 100%;
        max-width: 400px;
    }

    .about {
        padding-top: var(--section-spacing);
    }

    .about-container {
        grid-template-columns: 1fr;
    }

    .experience-badge {
        right: 0;
        bottom: 0;
        width: 120px;
        height: 120px;
    }

    .experience-badge .years {
        font-size: 1.5rem;
    }
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .hero-actions {
        flex-direction: column;
    }

    .cta-container {
        flex-direction: column;
        text-align: center;
    }

    .bottom-container {
        flex-direction: column;
        text-align: center;
    }
}