/* ==================== CSS Variables ==================== */
:root {
    --color-primary: #1a56db;
    --color-primary-light: #3b82f6;
    --color-primary-dark: #1e40af;
    --color-accent: #f59e0b;
    --color-accent-light: #fbbf24;
    --color-text: #111827;
    --color-text-light: #4b5563;
    --color-text-lighter: #6b7280;
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafc;
    --color-bg-dark: #0f172a;
    --color-border: #e5e7eb;
    --color-error: #dc2626;
    --color-success: #10b981;
    --font-main: 'Source Han Sans CN', 'Microsoft YaHei', 'PingFang SC', -apple-system, sans-serif;
    --font-display: 'Source Han Sans CN', 'Microsoft YaHei', 'PingFang SC', -apple-system, sans-serif;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --navbar-height: 70px;
}

/* ==================== Reset & Base ==================== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    /* 让锚点跳转不被固定导航栏遮挡 */
    scroll-padding-top: var(--navbar-height);
}

body {
    font-family: var(--font-main);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

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

ul {
    list-style: none;
}

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

/* ==================== Skip Link (无障碍) ==================== */
.skip-link {
    position: absolute;
    top: -100px;
    left: 16px;
    padding: 10px 20px;
    background: var(--color-primary);
    color: #fff;
    border-radius: var(--radius-sm);
    font-weight: 500;
    z-index: 10000;
    transition: top 0.2s;
}

.skip-link:focus {
    top: 16px;
    color: #fff;
    box-shadow: 0 0 0 3px rgba(26, 86, 219, 0.3);
}

/* ==================== Focus Styles (键盘无障碍) ==================== */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
    outline: 3px solid var(--color-primary);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

/* 移除 input/textarea 默认 outline，使用自定义 */
.form-group input:focus-visible,
.form-group textarea:focus-visible {
    outline: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ==================== Buttons ==================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-family: var(--font-main);
    font-weight: 500;
    border: none;
    cursor: pointer;
    transition: all var(--transition);
    border-radius: var(--radius-sm);
    letter-spacing: 0.02em;
    min-height: 44px;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
}

.btn-primary:hover:not(:disabled) {
    background: var(--color-primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 1.5px solid rgba(255, 255, 255, 0.5);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: #fff;
}

.btn-sm {
    padding: 8px 20px;
    font-size: 14px;
}

.btn-lg {
    padding: 14px 36px;
    font-size: 16px;
}

.btn-block {
    width: 100%;
    padding: 14px;
    font-size: 16px;
}

/* ==================== Navbar ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    transition: all var(--transition);
    background: transparent;
    min-height: var(--navbar-height);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: var(--shadow-sm);
    padding: 10px 0;
}

.navbar.scrolled .nav-logo .logo-text,
.navbar.scrolled .nav-links a {
    color: var(--color-text);
}

.navbar.scrolled .nav-logo .logo-icon {
    color: var(--color-primary);
}

.navbar.scrolled .nav-logo .nav-logo-img {
    filter: none;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 26px;
    font-weight: 700;
    color: #fff;
}

.logo-icon {
    color: var(--color-accent);
    font-size: 22px;
}

.nav-logo-img {
    height: 44px;
    width: auto;
    border-radius: 4px;
    /* 在深色背景上把 logo 反色显示 */
    filter: brightness(0) invert(1);
    transition: filter var(--transition);
}

.footer-logo-img {
    height: 44px;
    width: auto;
    border-radius: 4px;
    filter: brightness(0) invert(1);
}

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

.nav-links a {
    color: rgba(255, 255, 255, 0.85);
    font-size: 15px;
    font-weight: 400;
    position: relative;
    padding: 4px 0;
}

.nav-links a:hover {
    color: #fff;
}

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

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

.navbar.scrolled .nav-links a:hover {
    color: var(--color-primary);
}

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

.nav-toggle span {
    width: 24px;
    height: 2px;
    background: #fff;
    transition: all var(--transition);
}

.navbar.scrolled .nav-toggle span {
    background: var(--color-text);
}

/* ==================== Hero ==================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 40%, #1a56db 100%);
}

.hero-particles {
    position: absolute;
    inset: 0;
}

.hero-particles .particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 50%;
    animation: float linear infinite;
    will-change: transform, opacity;
}

@keyframes float {
    0% { transform: translateY(100vh) scale(0); opacity: 0; }
    10% { opacity: 1; }
    90% { opacity: 1; }
    100% { transform: translateY(-10vh) scale(1); opacity: 0; }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 120px 24px 80px;
    max-width: 800px;
}

.hero-badge {
    display: inline-block;
    padding: 6px 20px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 100px;
    color: var(--color-accent-light);
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 32px;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.hero-title {
    font-family: var(--font-display);
    font-size: clamp(36px, 6vw, 64px);
    font-weight: 700;
    color: #fff;
    line-height: 1.2;
    margin-bottom: 24px;
}

.title-line {
    display: block;
}

.hero-subtitle {
    font-size: clamp(14px, 2vw, 18px);
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 40px;
    letter-spacing: 0.05em;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 64px;
    flex-wrap: wrap;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 48px;
    padding-top: 40px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    flex-wrap: wrap;
}

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

.stat-number {
    font-size: 32px;
    font-weight: 700;
    color: #fff;
    font-family: var(--font-display);
    /* 防止布局抖动（counter 动画前的内容） */
    min-height: 1em;
    display: inline-block;
}

.stat-label {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 4px;
}

.hero-scroll {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
}

.hero-scroll a {
    display: flex;
    justify-content: center;
}

.hero-scroll span {
    display: block;
    width: 24px;
    height: 38px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 12px;
    position: relative;
}

.hero-scroll span::before {
    content: '';
    position: absolute;
    top: 6px;
    left: 50%;
    width: 4px;
    height: 8px;
    margin-left: -2px;
    background: rgba(255, 255, 255, 0.5);
    border-radius: 2px;
    animation: scrollDown 1.5s infinite;
}

@keyframes scrollDown {
    0% { opacity: 1; transform: translateY(0); }
    100% { opacity: 0; transform: translateY(12px); }
}

/* ==================== Section Common ==================== */
section[id] {
    /* 防止锚点跳转后被固定导航栏遮挡 */
    scroll-margin-top: var(--navbar-height);
}

.section-header {
    text-align: center;
    margin-bottom: 56px;
}

.section-header-left {
    text-align: left;
}

.section-tag {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 0.15em;
    color: var(--color-primary);
    background: rgba(26, 86, 219, 0.08);
    padding: 4px 16px;
    border-radius: 100px;
    margin-bottom: 16px;
}

.section-title {
    font-family: var(--font-display);
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 12px;
}

.section-title.text-left {
    text-align: left;
}

.section-desc {
    font-size: 16px;
    color: var(--color-text-light);
    max-width: 560px;
    margin: 0 auto;
}

.section-header-left .section-desc {
    margin: 0;
}

/* ==================== Features ==================== */
.features {
    padding: 100px 0;
    background: var(--color-bg-alt);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: #fff;
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
    border: 1px solid var(--color-border);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--color-primary);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: transparent;
}

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-card-large {
    grid-column: span 3;
    display: grid;
    grid-template-columns: auto 1fr auto;
    gap: 32px;
    align-items: center;
    padding: 40px 36px;
}

.feature-card-large .feature-title {
    font-size: 22px;
}

.feature-card-large .feature-desc {
    margin-bottom: 12px;
}

.feature-body {
    /* 让大卡片中间的描述区域占满可用空间 */
    min-width: 0;
}

.feature-action {
    font-size: 14px;
    color: var(--color-primary);
    font-weight: 500;
    white-space: nowrap;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    transition: background var(--transition);
}

.feature-action:hover {
    background: rgba(26, 86, 219, 0.08);
}

.feature-icon-wrap {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.feature-icon {
    width: 28px;
    height: 28px;
}

.feature-icon-blue { background: rgba(26, 86, 219, 0.1); color: var(--color-primary); }
.feature-icon-green { background: rgba(16, 185, 129, 0.1); color: #10b981; }
.feature-icon-purple { background: rgba(139, 92, 246, 0.1); color: #8b5cf6; }
.feature-icon-orange { background: rgba(245, 158, 11, 0.1); color: #f59e0b; }
.feature-icon-teal { background: rgba(20, 184, 166, 0.1); color: #14b8a6; }
.feature-icon-red { background: rgba(239, 68, 68, 0.1); color: #ef4444; }
.feature-icon-cyan { background: rgba(6, 182, 212, 0.1); color: #06b6d4; }

.feature-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 10px;
}

.feature-desc {
    font-size: 14px;
    color: var(--color-text-light);
    line-height: 1.6;
    margin-bottom: 16px;
}

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

.feature-list li {
    font-size: 13px;
    color: var(--color-text-light);
    background: var(--color-bg-alt);
    padding: 4px 12px;
    border-radius: 100px;
    white-space: nowrap;
}

.feature-card-large .feature-list li {
    background: rgba(26, 86, 219, 0.06);
    color: var(--color-primary);
}

/* ==================== About ==================== */
.about {
    padding: 100px 0;
    background: #fff;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}

.about-text {
    font-size: 15px;
    color: var(--color-text-light);
    line-height: 1.8;
    margin-bottom: 16px;
}

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

.about-highlights {
    display: flex;
    gap: 40px;
    margin-top: 36px;
    flex-wrap: wrap;
}

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

.highlight-number {
    font-size: 36px;
    font-weight: 700;
    color: var(--color-primary);
    font-family: var(--font-display);
}

.highlight-label {
    font-size: 13px;
    color: var(--color-text-light);
    margin-top: 4px;
}

.about-visual {
    display: flex;
    justify-content: center;
}

.visual-card {
    width: 100%;
    max-width: 420px;
    background: var(--color-bg-dark);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-xl);
}

.visual-header {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 16px 24px;
    background: rgba(255, 255, 255, 0.05);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    color: #fff;
    font-size: 15px;
    font-weight: 600;
}

.visual-logo {
    color: var(--color-accent);
}

.visual-badge {
    margin-left: auto;
    font-size: 11px;
    color: rgba(255, 255, 255, 0.4);
    font-weight: 400;
    letter-spacing: 0.08em;
}

.visual-body {
    padding: 48px 32px;
}

.visual-mission {
    text-align: center;
    position: relative;
}

.mission-quote {
    font-size: 72px;
    color: var(--color-primary);
    opacity: 0.5;
    font-family: Georgia, serif;
    line-height: 1;
    display: block;
    margin-bottom: -12px;
}

.visual-mission p {
    font-size: 22px;
    color: #fff;
    font-weight: 600;
    line-height: 1.6;
    letter-spacing: 0.05em;
}

.visual-footer {
    display: flex;
    gap: 10px;
    padding: 20px 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    flex-wrap: wrap;
}

.visual-tag {
    padding: 6px 16px;
    background: rgba(26, 86, 219, 0.2);
    color: var(--color-primary-light);
    border-radius: 100px;
    font-size: 13px;
}

/* ==================== News ==================== */
.news {
    padding: 100px 0;
    background: var(--color-bg-alt);
}

.news-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.news-card {
    background: #fff;
    border-radius: var(--radius-md);
    padding: 28px;
    border: 1px solid var(--color-border);
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.news-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

.news-card-featured {
    grid-row: span 2;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.news-category {
    display: inline-block;
    font-size: 12px;
    font-weight: 500;
    color: var(--color-primary);
    background: rgba(26, 86, 219, 0.08);
    padding: 3px 10px;
    border-radius: 4px;
    margin-bottom: 14px;
}

.news-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-text);
    line-height: 1.5;
    margin-bottom: 10px;
}

.news-card-featured .news-title {
    font-size: 20px;
}

.news-excerpt {
    font-size: 14px;
    color: var(--color-text-light);
    line-height: 1.6;
    margin-bottom: 16px;
}

.news-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: auto;
    gap: 12px;
}

.news-date {
    font-size: 13px;
    color: var(--color-text-lighter);
}

.news-link {
    font-size: 14px;
    color: var(--color-primary);
    font-weight: 500;
    white-space: nowrap;
}

.news-link:hover {
    color: var(--color-primary-dark);
}

/* ==================== Contact ==================== */
.contact {
    padding: 100px 0;
    background: #fff;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: start;
}

.contact-desc {
    font-size: 15px;
    color: var(--color-text-light);
    margin-bottom: 36px;
    line-height: 1.8;
}

.contact-items {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
}

.contact-icon {
    width: 44px;
    height: 44px;
    background: rgba(26, 86, 219, 0.08);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.contact-icon svg {
    width: 20px;
    height: 20px;
    color: var(--color-primary);
}

.contact-label {
    font-size: 13px;
    color: var(--color-text-lighter);
    margin-bottom: 2px;
}

.contact-value {
    font-size: 15px;
    color: var(--color-text);
    font-weight: 500;
    word-break: break-all;
}

a.contact-value:hover {
    color: var(--color-primary);
}

.contact-form-wrap {
    background: var(--color-bg-alt);
    border-radius: var(--radius-lg);
    padding: 36px;
    border: 1px solid var(--color-border);
}

.form-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--color-text);
}

.form-tip {
    font-size: 13px;
    color: var(--color-text-light);
    margin-bottom: 20px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--color-text);
    margin-bottom: 6px;
}

.required {
    color: var(--color-error);
    margin-left: 2px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-family: var(--font-main);
    font-size: 14px;
    color: var(--color-text);
    background: #fff;
    transition: border-color var(--transition), box-shadow var(--transition);
    outline: none;
    min-height: 44px;
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
    line-height: 1.6;
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(26, 86, 219, 0.1);
}

.form-group input:invalid:not(:placeholder-shown):not(:focus),
.form-group textarea:invalid:not(:placeholder-shown):not(:focus) {
    border-color: var(--color-error);
}

.form-group.has-error input,
.form-group.has-error textarea {
    border-color: var(--color-error);
    box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.08);
}

.form-error {
    display: block;
    font-size: 12px;
    color: var(--color-error);
    margin-top: 4px;
    min-height: 1em;
}

.form-status {
    margin-top: 12px;
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    display: none;
}

.form-status.success {
    display: block;
    background: rgba(16, 185, 129, 0.1);
    color: var(--color-success);
    border: 1px solid rgba(16, 185, 129, 0.2);
}

.form-status.error {
    display: block;
    background: rgba(220, 38, 38, 0.1);
    color: var(--color-error);
    border: 1px solid rgba(220, 38, 38, 0.2);
}

.btn-block {
    margin-top: 8px;
}

/* ==================== Back to Top ==================== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--color-primary);
    color: #fff;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    z-index: 999;
    transition: opacity var(--transition), transform var(--transition), background var(--transition);
    opacity: 0;
    transform: translateY(20px);
}

.back-to-top[hidden] {
    display: none;
}

.back-to-top.visible {
    opacity: 1;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
}

.back-to-top svg {
    width: 24px;
    height: 24px;
}

/* ==================== Footer ==================== */
.footer {
    background: var(--color-bg-dark);
    color: rgba(255, 255, 255, 0.7);
    padding: 64px 0 24px;
}

.footer a {
    color: rgba(255, 255, 255, 0.7);
}

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

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 48px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 26px;
    font-weight: 700;
    color: #fff;
    margin-bottom: 12px;
}

.footer-slogan {
    font-size: 14px;
    margin-bottom: 16px;
    color: rgba(255, 255, 255, 0.5);
}

.footer-copy {
    font-size: 13px;
    line-height: 1.7;
    color: rgba(255, 255, 255, 0.4);
}

.footer-links h4 {
    font-size: 14px;
    font-weight: 600;
    color: #fff;
    margin-bottom: 16px;
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-links li {
    font-size: 14px;
}

.footer-miniapp {
    color: var(--color-accent-light) !important;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    padding-top: 20px;
    text-align: center;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.4);
}

.footer-bottom a {
    color: rgba(255, 255, 255, 0.4);
}

/* ==================== Modal (文章占位) ==================== */
.article-modal {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    padding: 24px;
}

.article-modal.open {
    display: flex;
}

.article-modal-content {
    background: #fff;
    border-radius: var(--radius-lg);
    max-width: 640px;
    width: 100%;
    max-height: 80vh;
    overflow-y: auto;
    padding: 36px;
    position: relative;
    box-shadow: var(--shadow-xl);
}

.article-modal-close {
    position: absolute;
    top: 16px;
    right: 16px;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--color-text-light);
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition);
}

.article-modal-close:hover {
    background: var(--color-bg-alt);
    color: var(--color-text);
}

.article-modal-content h2 {
    font-size: 22px;
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 12px;
    padding-right: 32px;
}

.article-modal-meta {
    font-size: 13px;
    color: var(--color-text-light);
    margin-bottom: 20px;
}

.article-modal-body {
    font-size: 15px;
    color: var(--color-text-light);
    line-height: 1.8;
}

.article-modal-body p {
    margin-bottom: 12px;
}

.article-modal-body p strong {
    color: var(--color-text);
}

.article-modal-pending {
    background: rgba(245, 158, 11, 0.1);
    border-left: 3px solid var(--color-accent);
    padding: 12px 16px;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    font-size: 14px;
    color: var(--color-text);
    margin-top: 16px;
}

/* ==================== Responsive ==================== */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .feature-card-large {
        grid-column: span 2;
        grid-template-columns: auto 1fr;
    }
    .feature-action {
        grid-column: span 2;
        justify-self: start;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(255, 255, 255, 0.98);
        flex-direction: column;
        padding: 20px 24px;
        gap: 0;
        box-shadow: var(--shadow-lg);
    }
    .nav-links.open {
        display: flex;
    }
    .nav-links a {
        color: var(--color-text) !important;
        padding: 12px 0;
        border-bottom: 1px solid var(--color-border);
    }
    .nav-toggle {
        display: flex;
    }
    .nav-actions {
        display: none;
    }

    .hero-stats {
        gap: 24px;
    }
    .stat-number {
        font-size: 24px;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }
    .feature-card-large {
        grid-column: span 1;
        grid-template-columns: 1fr;
        text-align: center;
    }
    .feature-card-large .feature-icon-wrap {
        margin: 0 auto;
    }
    .feature-action {
        grid-column: auto;
        justify-self: center;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .news-grid {
        grid-template-columns: 1fr;
    }
    .news-card-featured {
        grid-row: auto;
    }

    .contact-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
    }

    .back-to-top {
        bottom: 24px;
        right: 24px;
        width: 44px;
        height: 44px;
    }
}

@media (max-width: 480px) {
    .hero-actions {
        flex-direction: column;
        align-items: stretch;
    }
    .hero-stats {
        flex-wrap: wrap;
        gap: 20px;
    }
    .form-row {
        grid-template-columns: 1fr;
    }
    .footer-grid {
        grid-template-columns: 1fr;
    }
    .about-highlights {
        gap: 24px;
    }
}

/* ==================== 用户偏好：减少动画 ==================== */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    .hero-particles .particle {
        display: none;
    }
}