/* ========================================
   牒蓝科技官网 - 优化版样式
   ======================================== */
:root {
    --primary-color: #1687CC;
    --primary-dark: #0F5A8A;
    --primary-light: #19B1F8;
    --secondary-color: #66F7DC;
    --accent-color: #00FFEB;
    --bg-dark: #0a2940;
    --bg-light: #F0FDFB;
    --bg-cyan: #E0F7F4;
    --text-dark: #0F172A;
    --text-light: #64748b;
    --white: #ffffff;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --transition: all 0.3s ease;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--white);
    overflow-x: hidden;
}

a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* ========================================
   滚动动画
   ======================================== */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========================================
   导航栏
   ======================================== */
.header {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid rgba(226, 232, 240, 0.8);
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.08);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo { display: flex; align-items: center; gap: 10px; }

.logo-img {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    object-fit: contain;
}

.logo-text {
    font-size: 22px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 36px;
}

.nav-menu a {
    font-size: 15px;
    font-weight: 500;
    color: var(--text-light);
    position: relative;
    padding: 4px 0;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    border-radius: 2px;
    transition: width 0.3s ease;
}

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

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 8px;
}

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: var(--transition);
}

/* ========================================
   按钮
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 32px;
    font-size: 15px;
    font-weight: 600;
    border-radius: 12px;
    border: none;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: var(--white);
    box-shadow: 0 4px 14px rgba(22, 135, 204, 0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(22, 135, 204, 0.45);
}

.btn-secondary {
    background: var(--white);
    color: var(--primary-color);
    border: 2px solid rgba(22, 135, 204, 0.3);
}

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

.btn-large {
    padding: 18px 40px;
    font-size: 17px;
    border-radius: 14px;
}

/* ========================================
   Hero区域（统一深色）
   ======================================== */
.hero, .product-hero {
    position: relative;
    min-height: 92vh;
    display: flex;
    align-items: center;
    padding: 120px 0 100px;
    background: linear-gradient(135deg, var(--bg-dark) 0%, #0d3a54 50%, #0a3d5c 100%);
    overflow: hidden;
}

.hero::before, .product-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 60% at 20% 40%, rgba(22, 135, 204, 0.18) 0%, transparent 70%),
        radial-gradient(ellipse 60% 50% at 75% 70%, rgba(102, 247, 220, 0.12) 0%, transparent 70%);
    pointer-events: none;
}

.hero .container, .product-hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 64px;
    position: relative;
    z-index: 1;
}

.hero-content, .product-hero-content {
    flex: 1;
    max-width: 520px;
}

.hero-title, .product-hero-title {
    font-size: 58px;
    font-weight: 800;
    line-height: 1.1;
    color: #ffffff;
    margin-bottom: 28px;
    letter-spacing: -1.5px;
}

.hero-subtitle, .product-hero-subtitle {
    font-size: 18px;
    line-height: 1.85;
    color: #94a3b8;
    margin-bottom: 44px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.product-badge {
    display: inline-block;
    padding: 8px 18px;
    background: rgba(22, 135, 204, 0.2);
    border: 1px solid rgba(22, 135, 204, 0.4);
    color: #19B1F8;
    font-size: 13px;
    font-weight: 600;
    border-radius: 24px;
    margin-bottom: 28px;
    letter-spacing: 0.02em;
}

/* Hero视觉区 */
.hero-visual, .product-hero-visual {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}

.logo-showcase {
    width: 300px;
    height: 300px;
    background: linear-gradient(145deg, rgba(255,255,255,0.95) 0%, #e8f4fd 100%);
    border-radius: 72px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
    box-shadow:
        0 30px 60px -15px rgba(0, 0, 0, 0.35),
        0 0 0 1px rgba(255, 255, 255, 0.1) inset;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-16px); }
}

.logo-showcase img {
    max-width: 220px;
    max-height: 220px;
    object-fit: contain;
}

.phone-stack {
    position: relative;
    width: 380px;
    height: 520px;
}

.phone-stack img {
    position: absolute;
    border-radius: 38px;
    box-shadow: 0 25px 55px -12px rgba(0, 0, 0, 0.4);
}

.phone-stack img:first-child {
    left: 0;
    top: 0;
    width: 280px;
    z-index: 2;
}

.phone-stack img:last-child {
    right: 0;
    bottom: 0;
    width: 230px;
    z-index: 1;
    opacity: 0.9;
}

/* ========================================
   通用区块
   ======================================== */
.section-header {
    text-align: center;
    margin-bottom: 68px;
}

.section-title {
    font-size: 42px;
    font-weight: 750;
    color: var(--text-dark);
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

.section-subtitle {
    font-size: 18px;
    color: var(--text-light);
    max-width: 560px;
    margin: 0 auto;
}

/* ========================================
   核心价值
   ======================================== */
.features {
    padding: 110px 0;
    background: linear-gradient(180deg, var(--white) 0%, var(--bg-cyan) 100%);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 28px;
}

.feature-card {
    background: var(--white);
    border-radius: 20px;
    padding: 36px 28px;
    text-align: center;
    transition: var(--transition);
    border: 1px solid rgba(226, 232, 240, 0.6);
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px -12px rgba(22, 135, 204, 0.18);
    border-color: rgba(22, 135, 204, 0.2);
}

.feature-icon {
    width: 68px;
    height: 68px;
    margin: 0 auto 24px;
    background: linear-gradient(135deg, rgba(22, 135, 204, 0.1), rgba(102, 247, 220, 0.08));
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
    transition: var(--transition);
}

.feature-card:hover .feature-icon {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: var(--white);
    transform: scale(1.05);
}

.feature-icon svg { width: 30px; height: 30px; }

.feature-title {
    font-size: 19px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.feature-desc {
    font-size: 14px;
    color: var(--text-light);
    line-height: 1.75;
}

/* ========================================
   产品展示
   ======================================== */
.products {
    padding: 110px 0;
    background: var(--white);
}

.product-preview {
    display: flex;
    align-items: center;
    gap: 72px;
}

.product-image {
    flex-shrink: 0;
}

.product-image .phone-stack {
    transform: scale(0.95);
}

.product-info { flex: 1; }

.product-tag {
    display: inline-block;
    padding: 6px 16px;
    background: linear-gradient(135deg, rgba(22, 135, 204, 0.1), rgba(102, 247, 220, 0.06));
    color: var(--primary-color);
    font-size: 13px;
    font-weight: 600;
    border-radius: 20px;
    margin-bottom: 20px;
    letter-spacing: 0.03em;
}

.product-name {
    font-size: 34px;
    font-weight: 750;
    color: var(--text-dark);
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.product-desc {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-light);
    margin-bottom: 28px;
}

.product-features {
    list-style: none;
    margin-bottom: 32px;
}

.product-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 0;
    font-size: 15px;
    font-weight: 500;
    color: var(--gray-700);
}

.product-features li svg {
    width: 22px;
    height: 22px;
    flex-shrink: 0;
    stroke: var(--secondary-color);
    stroke-width: 2.5;
}

/* ========================================
   关于我们
   ======================================== */
.about {
    padding: 110px 0;
    background: var(--bg-cyan);
}

.about-content {
    display: flex;
    align-items: center;
    gap: 80px;
}

.about-text {
    flex: 1;
}

.about-text p {
    font-size: 16px;
    line-height: 1.9;
    color: var(--text-light);
    margin-bottom: 20px;
}

.about-stats {
    display: flex;
    gap: 48px;
    flex-shrink: 0;
}

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

.stat-number {
    display: block;
    font-size: 48px;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.2;
}

.stat-label {
    font-size: 14px;
    color: var(--text-light);
    margin-top: 8px;
}

/* ========================================
   联系我们
   ======================================== */
.contact {
    padding: 110px 0;
    background: var(--white);
}

.contact-content {
    display: flex;
    gap: 64px;
}

.contact-info {
    flex: 0 0 360px;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 18px;
    padding: 20px;
    background: var(--bg-cyan);
    border-radius: 16px;
    transition: var(--transition);
}

.contact-item:hover {
    background: #d4f0ed;
    transform: translateX(6px);
}

.contact-icon {
    width: 52px;
    height: 52px;
    background: var(--white);
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    color: var(--primary-color);
}

.contact-icon svg { width: 24px; height: 24px; }

.contact-text h4 {
    font-size: 15px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.contact-text p {
    font-size: 14px;
    color: var(--text-light);
}

.contact-form {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 16px 20px;
    font-size: 15px;
    font-family: inherit;
    border: 2px solid var(--gray-200);
    border-radius: 14px;
    outline: none;
    transition: var(--transition);
    background: var(--gray-100);
    color: var(--text-dark);
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--primary-color);
    background: var(--white);
    box-shadow: 0 0 0 4px rgba(22, 135, 204, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 130px;
}

/* ========================================
   产品页 - 功能展示
   ======================================== */
.features-section {
    padding: 110px 0;
    background: linear-gradient(180deg, #f8fafc 0%, var(--white) 100%);
}

.features-section .features-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
}

.features-section .feature-card {
    background: var(--white);
    border-radius: 22px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    border: none;
    text-align: left;
    padding: 0;
}

.features-section .feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 24px 48px -12px rgba(22, 135, 204, 0.15);
}

.feature-screenshots {
    width: 100%;
    background: linear-gradient(145deg, #f0f7ff, #e3f2fd);
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: center;
    padding: 20px;
    gap: 14px;
    min-height: 200px;
}

.feature-screenshots img {
    max-width: 46%;
    max-height: 320px;
    border-radius: 12px;
    object-fit: cover;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    transition: var(--transition);
}

.feature-screenshots img:hover {
    transform: scale(1.04);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}

.feature-content {
    width: 100%;
    padding: 26px 30px;
}

.feature-tag {
    display: inline-block;
    padding: 5px 14px;
    background: linear-gradient(135deg, rgba(22, 135, 204, 0.08), rgba(102, 247, 220, 0.05));
    color: var(--primary-color);
    font-size: 12px;
    font-weight: 650;
    border-radius: 10px;
    margin-bottom: 14px;
    letter-spacing: 0.03em;
}

.feature-title {
    font-size: 21px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.feature-desc {
    font-size: 14.5px;
    line-height: 1.75;
    color: var(--text-light);
    margin-bottom: 18px;
}

.feature-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.feature-list span {
    padding: 6px 14px;
    background: var(--gray-100);
    border-radius: 8px;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-600);
    border: 1px solid var(--gray-200);
}

.feature-card.feature-large {
    grid-column: span 2;
}

.feature-card.feature-large .feature-screenshots {
    padding: 24px;
    min-height: 260px;
}

.feature-card.feature-large .feature-screenshots img {
    max-width: 29%;
    max-height: 340px;
}

.feature-card.feature-large .feature-content {
    padding: 34px 40px;
}

.feature-card.feature-large .feature-title {
    font-size: 26px;
}

.feature-card.feature-large .feature-list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
}

.feature-card.feature-large .feature-list span {
    padding: 10px 18px;
    font-size: 14px;
}

/* ========================================
   相册展示
   ======================================== */
.gallery-showcase {
    padding: 110px 0;
    background: linear-gradient(180deg, var(--white) 0%, var(--bg-cyan) 100%);
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.gallery-item {
    border-radius: 18px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    aspect-ratio: 9/19.5;
    background: var(--gray-100);
}

.gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.gallery-item:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 20px 40px -10px rgba(22, 135, 204, 0.2);
}

.gallery-item:hover img {
    transform: scale(1.08);
}

/* ========================================
   下载提示
   ======================================== */
.download-section {
    padding: 120px 0;
    background: linear-gradient(135deg, var(--bg-dark) 0%, #0d3a54 50%, #0a3d5c 100%);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.download-section::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 60% 50% at 50% 50%, rgba(22, 135, 204, 0.15) 0%, transparent 70%),
        radial-gradient(ellipse 50% 40% at 70% 30%, rgba(102, 247, 220, 0.1) 0%, transparent 60%);
    pointer-events: none;
}

.download-section .container { position: relative; z-index: 1; }

.download-title {
    font-size: 50px;
    font-weight: 800;
    color: #ffffff;
    margin-bottom: 20px;
    letter-spacing: -1px;
}

.download-desc {
    font-size: 18px;
    color: #94a3b8;
    margin-bottom: 44px;
    line-height: 1.8;
}

/* ========================================
   页脚
   ======================================== */
.footer {
    padding: 72px 0 28px;
    background: var(--gray-900);
    color: var(--gray-400);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    gap: 60px;
    padding-bottom: 48px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--white);
    display: inline-block;
    margin-bottom: 12px;
}

.footer-desc {
    font-size: 15px;
    color: var(--gray-400);
    max-width: 280px;
}

.footer-links {
    display: flex;
    gap: 80px;
}

.footer-column h4 {
    font-size: 15px;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 20px;
}

.footer-column ul {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-column ul a {
    font-size: 14px;
    color: var(--gray-400);
    transition: var(--transition);
}

.footer-column ul a:hover {
    color: var(--white);
    padding-left: 4px;
}

.footer-bottom {
    text-align: center;
    font-size: 13px;
    padding-top: 28px;
    color: var(--gray-500);
}

.footer-bottom p {
    margin: 8px 0;
}

.beian-info {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
}

.beian-info a {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    color: var(--gray-500);
    text-decoration: none;
    transition: color 0.3s ease;
}

.beian-info a:hover {
    color: var(--gray-300);
}

.beian-icon {
    width: 16px;
    height: 16px;
    vertical-align: middle;
}

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 1200px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 1024px) {
    .hero .container,
    .product-hero .container {
        flex-direction: column;
        text-align: center;
        padding-top: 140px;
    }

    .hero, .product-hero { min-height: auto; padding: 140px 0 80px; }

    .hero-content, .product-hero-content { max-width: 100%; }

    .hero-buttons { justify-content: center; }

    .phone-stack { transform: scale(0.88); }

    .product-preview { flex-direction: column; }

    .about-content { flex-direction: column; gap: 48px; }

    .contact-content { flex-direction: column; }

    .contact-info { flex: none; width: 100%; }

    .features-section .features-grid { grid-template-columns: 1fr; }

    .feature-card.feature-large { grid-column: span 1; }

    .feature-card.feature-large .feature-screenshots img { max-width: 46%; }

    .feature-card.feature-large .feature-list { grid-template-columns: 1fr; }

    .footer-content { flex-direction: column; gap: 40px; }

    .footer-links { gap: 48px; }

    .gallery-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .container { padding: 0 16px; }

    .nav-menu { display: none; }

    .nav-toggle { display: flex; }

    .section-title { font-size: 32px; }

    .hero-title, .product-hero-title { font-size: 38px; }

    .features-grid { grid-template-columns: 1fr; gap: 20px; }

    .about-stats { gap: 32px; flex-wrap: wrap; justify-content: center; }

    .stat-number { font-size: 36px; }

    .download-title { font-size: 34px; }

    .gallery-grid { grid-template-columns: 1fr; }

    .feature-screenshots img { max-width: 46%; }

    .logo-showcase { width: 240px; height: 240px; border-radius: 56px; padding: 30px; }
}