/* ===========================
   CSS 变量 / 设计令牌
   =========================== */
:root {
    --brand-primary: #1e88e5;
    --brand-primary-dark: #1565c0;
    --brand-primary-light: #64b5f6;
    --ink-900: #0f1a2e;
    --ink-700: #2a3a52;
    --ink-500: #54627a;
    --ink-300: #98a2b3;
    --ink-100: #e6eaf0;
    --bg-50: #f7f9fc;
    --bg-100: #eef2f7;
    --surface: #ffffff;
    --shadow-sm: 0 1px 2px rgba(15, 26, 46, 0.06);
    --shadow-md: 0 8px 24px rgba(15, 26, 46, 0.08);
    --shadow-lg: 0 20px 48px rgba(15, 26, 46, 0.12);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
}

/* ===========================
   全局样式
   =========================== */
* {
    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', Arial, sans-serif;
    line-height: 1.6;
    color: var(--ink-700);
    background-color: var(--bg-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

a {
    text-decoration: none;
    color: var(--ink-700);
    transition: color 0.2s var(--ease);
}

ul {
    list-style: none;
}

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

/* ===========================
   按钮系统
   =========================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 26px;
    border-radius: var(--radius-sm);
    font-weight: 500;
    font-size: 15px;
    letter-spacing: 0.3px;
    transition: all 0.25s var(--ease);
    border: 1px solid transparent;
    cursor: pointer;
    user-select: none;
    line-height: 1.4;
}

.btn-primary {
    background: var(--brand-primary);
    color: #fff;
    box-shadow: 0 4px 12px rgba(30, 136, 229, 0.25);
}

.btn-primary:hover {
    background: var(--brand-primary-dark);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(30, 136, 229, 0.35);
}

.btn-ghost {
    background: transparent;
    color: #fff;
    border-color: rgba(255, 255, 255, 0.4);
}

.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.12);
    border-color: rgba(255, 255, 255, 0.7);
    color: #fff;
    transform: translateY(-2px);
}

.btn:not(.btn-primary):not(.btn-ghost) {
    background: var(--brand-primary);
    color: #fff;
}

.btn:not(.btn-primary):not(.btn-ghost):hover {
    background: var(--brand-primary-dark);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ===========================
   章节标题
   =========================== */
.section-title {
    text-align: center;
    margin-bottom: 48px;
}

.section-title h2 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 14px;
    position: relative;
    display: inline-block;
    color: var(--ink-900);
    letter-spacing: -0.5px;
}

.underline {
    height: 3px;
    width: 48px;
    background: var(--brand-primary);
    margin: 0 auto;
    border-radius: 2px;
}

/* ===========================
   头部导航
   =========================== */
header {
    background-color: rgba(255, 255, 255, 0.92);
    backdrop-filter: saturate(180%) blur(10px);
    -webkit-backdrop-filter: saturate(180%) blur(10px);
    box-shadow: var(--shadow-sm);
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    border-bottom: 1px solid var(--ink-100);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 14px 15px;
}

.logo h1 {
    font-size: 22px;
    font-weight: 700;
    color: var(--brand-primary);
    letter-spacing: -0.3px;
}

nav ul {
    display: flex;
}

nav ul li {
    margin-left: 32px;
}

nav ul li a {
    font-size: 15px;
    font-weight: 500;
    padding: 8px 0;
    position: relative;
    color: var(--ink-500);
}

nav ul li a:hover,
nav ul li a.active {
    color: var(--ink-900);
}

nav ul li a:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--brand-primary);
    transition: width 0.25s var(--ease);
    border-radius: 1px;
}

nav ul li a:hover:after,
nav ul li a.active:after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    cursor: pointer;
    font-size: 22px;
    color: var(--ink-700);
}

/* ===========================
   Hero 品牌区
   =========================== */
.banner {
    position: relative;
    height: 600px;
    overflow: hidden;
    margin-top: 64px;
    background: var(--ink-900);
}

.slider {
    position: absolute;
    inset: 0;
    z-index: 1;
    display: none;
}

.hero {
    position: relative;
    z-index: 5;
    height: 100%;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg,
        rgba(15, 26, 46, 0.78) 0%,
        rgba(15, 26, 46, 0.55) 50%,
        rgba(30, 136, 229, 0.55) 100%);
}

.hero-inner {
    max-width: 760px;
    color: #fff;
    animation: fadeUp 0.8s var(--ease) 0.15s both;
}

@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 1.2px;
    color: rgba(255, 255, 255, 0.9);
    text-transform: uppercase;
    margin-bottom: 20px;
    padding: 6px 14px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 100px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}

.eyebrow-dot {
    width: 6px;
    height: 6px;
    background: var(--brand-primary-light);
    border-radius: 50%;
    box-shadow: 0 0 0 3px rgba(100, 181, 246, 0.25);
    display: inline-block;
}

.eyebrow-divider {
    opacity: 0.5;
    margin: 0 2px;
}

.hero-title {
    font-size: 64px;
    font-weight: 800;
    line-height: 1.05;
    color: #fff;
    margin-bottom: 14px;
    letter-spacing: -1.5px;
}

.hero-subtitle {
    font-size: 17px;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 24px;
    letter-spacing: 0.2px;
}

.hero-tagline {
    font-size: 24px;
    font-weight: 400;
    color: rgba(255, 255, 255, 0.85);
    line-height: 1.5;
    margin-bottom: 40px;
    letter-spacing: 0.3px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
}

/* ===========================
   About 页 Page Header
   =========================== */
.page-header {
    background: linear-gradient(135deg, var(--ink-900) 0%, #1c2c4a 60%, var(--brand-primary) 130%);
    padding: 130px 0 70px;
    color: #fff;
    position: relative;
    overflow: hidden;
}

.page-header::before {
    content: '';
    position: absolute;
    top: -40%;
    right: -10%;
    width: 60%;
    height: 180%;
    background: radial-gradient(circle, rgba(30, 136, 229, 0.25) 0%, transparent 70%);
    pointer-events: none;
}

.page-header-inner {
    position: relative;
    max-width: 760px;
    animation: fadeUp 0.8s var(--ease) 0.1s both;
}

.page-header-title {
    font-size: 44px;
    font-weight: 700;
    line-height: 1.15;
    color: #fff;
    margin-bottom: 14px;
    letter-spacing: -0.8px;
}

.page-header-subtitle {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.85);
    line-height: 1.6;
    max-width: 600px;
}

/* ===========================
   公司简介（首页）
   =========================== */
.about-preview {
    padding: 96px 0;
    background-color: var(--surface);
}

.about-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 40px;
}

.about-text {
    flex: 1;
    min-width: 280px;
    padding-right: 20px;
}

.about-text p {
    font-size: 16px;
    line-height: 1.85;
    margin-bottom: 28px;
    color: var(--ink-500);
}

.about-image {
    flex: 1;
    min-width: 280px;
    text-align: center;
}

.about-image img {
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    max-width: 100%;
    height: auto;
    transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease);
}

.about-image img:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

/* ===========================
   关于我们（关于页）
   =========================== */
.about-section {
    padding: 80px 0;
    background-color: var(--surface);
}

.about-full {
    max-width: 880px;
    margin: 0 auto;
    font-size: 16px;
    line-height: 1.95;
    color: var(--ink-500);
    background: var(--bg-50);
    padding: 48px 56px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--ink-100);
}

.about-full p {
    margin-bottom: 20px;
    color: var(--ink-500);
}

.about-full p:last-child {
    margin-bottom: 0;
}

.about-full p:first-child::first-letter {
    color: var(--brand-primary);
    font-weight: 700;
    font-size: 1.1em;
}

/* ===========================
   底部信息
   =========================== */
footer {
    background: var(--ink-900);
    color: rgba(255, 255, 255, 0.85);
    padding: 64px 0 24px;
    position: relative;
    overflow: hidden;
}

footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent 0%, var(--brand-primary) 50%, transparent 100%);
    opacity: 0.6;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 40px;
    margin-bottom: 40px;
    position: relative;
}

.footer-logo {
    flex: 1;
    min-width: 280px;
    padding-right: 40px;
}

.footer-logo h2 {
    font-size: 20px;
    margin-bottom: 14px;
    color: #fff;
    font-weight: 600;
    letter-spacing: -0.2px;
}

.footer-logo p {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
    line-height: 1.7;
}

.footer-contact {
    min-width: 240px;
}

.footer-contact h3 {
    font-size: 16px;
    margin-bottom: 18px;
    position: relative;
    padding-bottom: 10px;
    color: #fff;
    font-weight: 600;
}

.footer-contact h3:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 28px;
    height: 2px;
    background: var(--brand-primary);
    border-radius: 1px;
}

.footer-contact p {
    margin-bottom: 10px;
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
}

.footer-contact p i {
    margin-right: 10px;
    color: var(--brand-primary-light);
    font-size: 14px;
    width: 16px;
    text-align: center;
}

.footer-bottom {
    text-align: center;
    padding-top: 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    position: relative;
}

.footer-bottom p {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.5);
    letter-spacing: 0.2px;
}

.icp {
    margin-left: 10px;
}

.icp a {
    color: rgba(255, 255, 255, 0.5);
    transition: color 0.2s var(--ease);
}

.icp a:hover {
    color: var(--brand-primary-light);
}

/* ===========================
   响应式设计
   =========================== */
@media screen and (max-width: 992px) {
    .hero-title {
        font-size: 56px;
    }

    .hero-tagline {
        font-size: 22px;
    }

    .about-text,
    .about-image {
        flex: 100%;
        min-width: 0;
        padding-right: 0;
    }

    .about-text {
        margin-bottom: 32px;
    }

    .footer-logo,
    .footer-contact {
        flex-basis: 100%;
        padding-right: 0;
    }

    .about-full {
        padding: 36px 32px;
    }
}

@media screen and (max-width: 768px) {
    .mobile-menu-btn {
        display: block;
    }

    nav {
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        background: var(--surface);
        box-shadow: var(--shadow-sm);
        padding: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s var(--ease);
        border-bottom: 1px solid var(--ink-100);
    }

    nav.active {
        max-height: 300px;
    }

    nav ul {
        flex-direction: column;
        padding: 16px 0;
    }

    nav ul li {
        margin: 0;
        text-align: center;
    }

    nav ul li a {
        display: block;
        padding: 12px;
    }

    .banner {
        height: 540px;
        margin-top: 60px;
    }

    .hero-title {
        font-size: 44px;
        letter-spacing: -1px;
    }

    .hero-subtitle {
        font-size: 15px;
    }

    .hero-tagline {
        font-size: 18px;
        margin-bottom: 24px;
    }

    .hero-meta {
        margin-bottom: 28px;
    }

    .meta-chip {
        font-size: 12px;
        padding: 6px 12px;
    }

    .hero-actions {
        gap: 10px;
    }

    .btn {
        padding: 10px 22px;
        font-size: 14px;
    }

    .page-header {
        padding: 110px 0 50px;
    }

    .page-header-title {
        font-size: 32px;
    }

    .page-header-subtitle {
        font-size: 16px;
    }

    .about-preview,
    .about-section {
        padding: 64px 0;
    }

    .about-full {
        padding: 28px 24px;
        font-size: 15px;
        line-height: 1.85;
    }
}

@media screen and (max-width: 576px) {
    .banner {
        height: 480px;
    }

    .hero-eyebrow {
        font-size: 11px;
        padding: 5px 12px;
        margin-bottom: 16px;
    }

    .hero-title {
        font-size: 36px;
    }

    .hero-tagline {
        font-size: 16px;
    }

    .section-title h2 {
        font-size: 26px;
    }

    .page-header-title {
        font-size: 26px;
    }
}