/* ===== 重置与基础设置 ===== */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
    font-weight: 400;
    line-height: 1.75;
    color: #1A1A1A;
    background-color: #FFFFFF;
    text-rendering: optimizeLegibility;
}

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

a {
    color: #0B1B3A;
    text-decoration: none;
}

a:hover {
    color: #FF7A00;
}

ul,
ol {
    list-style: none;
}

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

:focus-visible {
    outline: 3px solid #FF7A00;
    outline-offset: 2px;
    border-radius: 4px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

.skip-link {
    position: fixed;
    top: 16px;
    left: 16px;
    z-index: 2000;
    padding: 12px 24px;
    background: #C6FF00;
    color: #000000;
    font-weight: 700;
    border-radius: 100px;
    transform: translateY(-200%);
    transition: transform 0.2s ease;
}

.skip-link:focus {
    transform: translateY(0);
}

/* ===== CSS 变量 ===== */
:root {
    --color-deep-blue: #0B1B3A;
    --color-neon-green: #C6FF00;
    --color-orange: #FF7A00;
    --color-black: #000000;
    --color-white: #FFFFFF;
    --color-light-gray: #F5F5F5;
    --color-dark-gray: #1A1A1A;
    --color-medium-gray: #666666;
    --font-title: "Noto Sans SC", "PingFang SC", sans-serif;
    --font-body: "Noto Sans SC", "PingFang SC", sans-serif;
    --header-height: 80px;
    --container-max: 1280px;
    --radius-pill: 100px;
    --radius-chamfer: 24px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== 通用布局系统 ===== */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: 96px 24px;
    position: relative;
}

.section-dark {
    background-color: var(--color-deep-blue);
    color: var(--color-white);
}

.section-light {
    background-color: var(--color-light-gray);
    color: var(--color-dark-gray);
}

/* ===== 头部与导航 ===== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(11, 27, 58, 0.88);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.site-header-inner {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
    height: var(--header-height);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
}

.brand-mark {
    font-weight: 900;
    font-size: 1.4rem;
    line-height: 1;
    background: var(--color-neon-green);
    color: var(--color-black);
    padding: 8px 12px;
    border-radius: 8px;
    clip-path: polygon(0 0, 100% 0, calc(100% - 8px) 100%, 0 100%);
}

.brand-text {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
}

.brand-text strong {
    font-size: 1.2rem;
    font-weight: 900;
    color: var(--color-white);
    letter-spacing: 0.02em;
}

.brand-text small {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--color-neon-green);
    letter-spacing: 0.15em;
}

.nav-capsule {
    display: flex;
}

.nav-capsule ul {
    display: flex;
    gap: 4px;
    background: rgba(0, 0, 0, 0.6);
    padding: 6px;
    border-radius: var(--radius-pill);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.nav-capsule a {
    display: block;
    padding: 10px 20px;
    border-radius: var(--radius-pill);
    color: var(--color-white);
    font-weight: 500;
    font-size: 0.95rem;
    white-space: nowrap;
    transition: background-color var(--transition), color var(--transition);
}

.nav-capsule a:hover {
    background: rgba(198, 255, 0, 0.2);
    color: var(--color-neon-green);
}

.nav-capsule a[aria-current="page"] {
    background: var(--color-neon-green);
    color: var(--color-black);
    font-weight: 700;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    padding: 10px;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.1);
}

.nav-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--color-white);
    border-radius: 2px;
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* ===== 滚动进度条 ===== */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 4px;
    width: 0;
    background: linear-gradient(90deg, var(--color-neon-green), var(--color-orange));
    z-index: 1500;
    transition: width 0.1s linear;
}

/* ===== 页脚 ===== */
.site-footer {
    position: relative;
    background-color: var(--color-deep-blue);
    color: var(--color-white);
    margin-top: 96px;
    clip-path: polygon(0 40px, 100% 0, 100% 100%, 0 100%);
    padding-top: 80px;
}

.site-footer-inner {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 48px 24px 24px;
}

.footer-top {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
    padding-bottom: 48px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.brand-footer {
    margin-bottom: 16px;
}

.footer-brand-block p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
    margin-bottom: 24px;
    max-width: 320px;
}

.footer-nav-block h4,
.footer-contact-block h4,
.footer-legal-block h4 {
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--color-neon-green);
    margin-bottom: 16px;
}

.footer-nav-block ul,
.footer-contact-block ul,
.footer-legal-block ul {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-nav-block a,
.footer-contact-block a,
.footer-legal-block a {
    color: rgba(255, 255, 255, 0.8);
    transition: color var(--transition);
}

.footer-nav-block a:hover,
.footer-contact-block a:hover,
.footer-legal-block a:hover {
    color: var(--color-orange);
}

.footer-contact-block li {
    color: rgba(255, 255, 255, 0.8);
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
    padding-top: 24px;
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.85rem;
}

/* ===== 返回顶部按钮 ===== */
.back-top {
    position: fixed;
    bottom: 48px;
    right: 48px;
    z-index: 900;
    width: 64px;
    height: 64px;
    border-radius: 100px;
    background: var(--color-neon-green);
    color: var(--color-black);
    font-weight: 900;
    font-size: 0.85rem;
    letter-spacing: 0.1em;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
    opacity: 0;
    visibility: hidden;
    transform: translateY(16px);
    transition: opacity var(--transition), transform var(--transition), visibility var(--transition);
    clip-path: polygon(0 20%, 20% 0, 100% 0, 100% 80%, 80% 100%, 0 100%);
}

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

.back-top:hover {
    background: var(--color-orange);
    color: var(--color-white);
}

/* ===== 通用按钮组件 ===== */
.btn-sport {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background: var(--color-neon-green);
    color: var(--color-black);
    font-weight: 700;
    font-size: 1rem;
    padding: 14px 32px;
    border-radius: 100px;
    transition: background-color var(--transition), transform var(--transition), box-shadow var(--transition);
    box-shadow: 0 0 0 rgba(198, 255, 0, 0);
}

.btn-sport:hover {
    background: var(--color-orange);
    color: var(--color-white);
    transform: translateY(-2px);
    box-shadow: 0 12px 32px rgba(198, 255, 0, 0.3);
}

.btn-outline {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--color-neon-green);
    color: var(--color-neon-green);
    font-weight: 600;
    font-size: 0.95rem;
    padding: 12px 28px;
    border-radius: 100px;
    transition: background-color var(--transition), color var(--transition), transform var(--transition);
}

.btn-outline:hover {
    background: var(--color-neon-green);
    color: var(--color-black);
    transform: translateY(-2px);
}

.btn-small {
    padding: 8px 20px;
    font-size: 0.85rem;
}

/* ===== 面包屑 ===== */
.breadcrumbs {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    padding: 24px 0;
    font-size: 0.9rem;
    color: var(--color-medium-gray);
}

.breadcrumbs a {
    color: var(--color-deep-blue);
    font-weight: 500;
}

.breadcrumbs a:hover {
    color: var(--color-orange);
}

.breadcrumbs span[aria-current="page"] {
    color: var(--color-medium-gray);
    font-weight: 600;
}

.breadcrumbs .breadcrumb-sep {
    color: var(--color-medium-gray);
    opacity: 0.5;
}

/* ===== 图片占位容器 ===== */
.image-placeholder {
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, var(--color-deep-blue), var(--color-black));
    border-radius: var(--radius-chamfer);
    clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
    min-height: 200px;
}

.image-placeholder::before {
    content: "";
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    background: linear-gradient(135deg, rgba(198, 255, 0, 0.15), rgba(11, 27, 58, 0) 60%), repeating-linear-gradient(-45deg, rgba(255, 255, 255, 0.03) 0 10px, transparent 10px 20px);
}

.ratio-16x9 {
    aspect-ratio: 16 / 9;
    width: 100%;
}

.ratio-4x3 {
    aspect-ratio: 4 / 3;
    width: 100%;
}

.ratio-1x1 {
    aspect-ratio: 1 / 1;
    width: 100%;
}

/* ===== 数据面板与统计线 ===== */
.panel-corner {
    background: var(--color-white);
    border-radius: var(--radius-chamfer);
    padding: 32px;
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.08);
    clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
}

.stat-line {
    display: flex;
    align-items: baseline;
    gap: 8px;
    padding: 8px 0;
    border-bottom: 1px solid rgba(11, 27, 58, 0.1);
}

.stat-line .stat-value {
    font-size: 1.75rem;
    font-weight: 900;
    color: var(--color-deep-blue);
}

.stat-line .stat-label {
    font-size: 0.9rem;
    color: var(--color-medium-gray);
}

.stat-line .stat-tag {
    margin-left: auto;
    font-size: 0.75rem;
    font-weight: 600;
    padding: 4px 12px;
    background: var(--color-neon-green);
    border-radius: 100px;
    color: var(--color-black);
}

/* ===== 页面结构 ===== */
.page-hero {
    background: var(--color-deep-blue);
    color: var(--color-white);
    padding: 72px 24px;
    position: relative;
    overflow: hidden;
}

.page-hero::after {
    content: "";
    position: absolute;
    right: -10%;
    top: -20%;
    width: 60%;
    height: 140%;
    background: linear-gradient(135deg, transparent 30%, rgba(198, 255, 0, 0.08) 100%);
    transform: skewX(-12deg);
}

.page-hero .container {
    position: relative;
    z-index: 2;
}

.page-title {
    font-family: var(--font-title);
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 900;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.page-subtitle {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.7);
    max-width: 600px;
    margin-top: 16px;
}

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
    .footer-top {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .site-header-inner {
        height: 64px;
    }

    .brand-text small {
        display: none;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-capsule {
        position: fixed;
        top: calc(64px + 16px);
        left: 16px;
        right: 16px;
        background: rgba(0, 0, 0, 0.9);
        backdrop-filter: blur(24px);
        border-radius: 24px;
        padding: 16px;
        border: 1px solid rgba(255, 255, 255, 0.1);
        opacity: 0;
        visibility: hidden;
        transform: translateY(-12px);
        transition: opacity var(--transition), transform var(--transition), visibility var(--transition);
    }

    .nav-capsule[data-open] {
        opacity: 1;
        visibility: visible;
        transform: translateY(0);
    }

    .nav-capsule ul {
        flex-direction: column;
        background: none;
        border: none;
        gap: 4px;
    }

    .nav-capsule a {
        padding: 14px 20px;
        border-radius: 16px;
    }

    .section {
        padding: 64px 20px;
    }

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

    .back-top {
        bottom: 24px;
        right: 24px;
        width: 56px;
        height: 56px;
    }
}

@media (max-width: 480px) {
    .brand-text strong {
        font-size: 1rem;
    }

    .brand-mark {
        font-size: 1.1rem;
    }
}

/* ===== 无障碍与动画偏好 ===== */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

::selection {
    background: var(--color-neon-green);
    color: var(--color-black);
}

/* 通用磨砂玻璃效果 */
.glass-panel {
    background: rgba(11, 27, 58, 0.6);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-chamfer);
}

/* 章节编号装饰 */
.section-number {
    font-size: 0.85rem;
    font-weight: 700;
    letter-spacing: 0.2em;
    color: var(--color-medium-gray);
    display: inline-flex;
    align-items: center;
    gap: 12px;
}

.section-number::before {
    content: "";
    display: inline-block;
    width: 32px;
    height: 2px;
    background: var(--color-neon-green);
}

/* 内容网格 */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 48px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

@media (max-width: 768px) {
    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
        gap: 32px;
    }
}