/* ============================================
   双弧智绘 WAAM 官网 — 导航栏+Hero 简洁版 CSS
   美学：暖白底 + 橙/琥珀色 + 工业力量感
   动效：已删除，保持简洁
   ============================================ */

/* ---------- 变量 ---------- */
:root {
    /* 暖白主色调 */
    --bg-primary: #fafaf9;
    --bg-secondary: #f5f4f0;
    --bg-card: #ffffff;
    --bg-dark: #1a1a1a;

    /* 文字层次 */
    --text-primary: rgba(0, 0, 0, 0.92);
    --text-secondary: #5c5a56;
    --text-muted: #9a9895;

    /* 电弧品牌色 */
    --arc-orange: #e85d04;
    --arc-amber: #f48c06;
    --arc-yellow: #faa307;
    --arc-red: #dc2f02;

    /* 强调色 */
    --accent: var(--arc-orange);
    --accent-hover: #d14d00;
    --accent-light: var(--arc-amber);
    --accent-bg: rgba(232, 93, 4, 0.06);

    /* 边框 */
    --border: rgba(0, 0, 0, 0.08);
    --border-hover: rgba(0, 0, 0, 0.15);

    /* 阴影 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);

    /* 字体 */
    --font-main: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

    /* 尺寸 */
    --nav-height: 62px;
    --container-max: 1160px;
    --container-pad: 4rem;

    /* 圆角 */
    --radius-xs: 4px;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-pill: 9999px;

    /* 动效 */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
    scroll-behavior: smooth;
    scrollbar-width: thin;
    scrollbar-color: var(--arc-amber) var(--bg-secondary);
    font-size: 16px;
    overflow-x: hidden;
    width: 100vw;
}

::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: var(--bg-secondary); }
::-webkit-scrollbar-thumb { background: rgba(232, 93, 4, 0.25); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--arc-amber); }

body {
    font-family: var(--font-main);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.8;
    width: 100%;
    max-width: 100vw;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

::selection {
    background: rgba(232, 93, 4, 0.15);
    color: var(--text-primary);
}

/* ---------- 容器 ---------- */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-pad);
}

.section {
    padding: 5rem 0;
    position: relative;
}

/* ============================================
   导航栏 — 简洁固定导航
   ============================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--nav-height);
    background: rgba(250, 250, 249, 0.92);
    backdrop-filter: blur(16px) saturate(180%);
    -webkit-backdrop-filter: blur(16px) saturate(180%);
    border-bottom: 1px solid var(--border);
}

/* 滚动进度条 */
.nav-progress {
    position: absolute;
    bottom: 0;
    left: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--arc-orange), var(--arc-amber));
    width: 0%;
    z-index: 1;
    transition: width 0.08s linear;
    box-shadow: 0 0 8px rgba(232, 93, 4, 0.5);
}

.nav-progress.active {
    box-shadow: 0 0 12px rgba(232, 93, 4, 0.7), 0 0 24px rgba(244, 140, 6, 0.3);
}

.nav-inner {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-pad);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* Logo */
.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--text-primary);
    z-index: 1001;
}

.nav-logo img {
    width: 32px;
    height: 32px;
    object-fit: contain;
}

/* 桌面端导航链接 */
.nav-links {
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.nav-link {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
    padding: 0.4rem 0.8rem;
    border-radius: var(--radius-sm);
    transition: color 0.2s, background 0.2s;
}

.nav-link:hover {
    color: var(--text-primary);
    background: rgba(0, 0, 0, 0.04);
}

.nav-link.active {
    color: var(--accent);
    background: var(--accent-bg);
    font-weight: 600;
}

.nav-blog {
    color: var(--accent) !important;
    border: 1px solid var(--accent);
    font-weight: 600;
}

.nav-blog:hover {
    background: var(--accent) !important;
    color: #fff !important;
}

/* 汉堡按钮 */
.nav-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    cursor: pointer;
    padding: 8px;
    background: rgba(0,0,0,0.04);
    border: none;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-sm);
    transition: background 0.2s;
    z-index: 1001;
}

.nav-toggle:hover {
    background: rgba(0,0,0,0.1);
}

.nav-toggle span {
    display: block;
    width: 20px;
    height: 2px;
    background: #1c1917;
    border-radius: 2px;
    transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), opacity 0.3s;
    transform-origin: center;
}

/* 移动端遮罩层 */
.nav-backdrop {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.45);
    z-index: 998;
    opacity: 0;
    transition: opacity 0.3s;
}

/* ============================================
   移动端菜单面板 — 768px 以下才生效
   ============================================ */
@media (max-width: 768px) {
    /* 移动端菜单面板 */
    .nav-links {
        display: flex;
        position: fixed;
        top: 0;
        right: -100%;
        width: min(280px, 80vw);
        height: 100vh;
        background: #1c1917;
        flex-direction: column;
        justify-content: flex-start;
        padding-top: 0;
        border-left: none;
        transition: right 0.35s cubic-bezier(0.16, 1, 0.3, 1);
        z-index: 999;
        box-shadow: -12px 0 60px rgba(0,0,0,0.35);
        overflow-y: auto;
    }

    /* 菜单顶部区域 */
    .nav-links::before {
        content: '';
        display: block;
        height: var(--nav-height);
        border-bottom: 1px solid rgba(255,255,255,0.06);
        flex-shrink: 0;
    }

    /* 关闭提示 */
    .nav-links::after {
        content: '✕';
        position: absolute;
        top: 14px;
        right: 16px;
        font-size: 1.2rem;
        color: rgba(255,255,255,0.35);
        width: 36px;
        height: 36px;
        display: flex;
        align-items: center;
        justify-content: center;
        border-radius: 50%;
        background: rgba(255,255,255,0.06);
        transition: background 0.2s, color 0.2s;
        pointer-events: none;
    }

    .nav-links.active {
        right: 0;
    }

    /* 汉堡变 X 动画（移动端激活态） */
    .nav-toggle.active span:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
        transform: scaleX(0);
    }
    .nav-toggle.active span:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }

    .nav-backdrop.active {
        opacity: 1;
        pointer-events: auto;
    }

    /* 移动端菜单链接 */
    .nav-links .nav-link {
        font-size: 0.92rem;
        padding: 1rem 1.5rem;
        color: rgba(255,255,255,0.7);
        border-bottom: 1px solid rgba(255,255,255,0.06);
        display: flex;
        align-items: center;
        gap: 0.75rem;
        transition: background 0.2s, color 0.2s;
        letter-spacing: 0.02em;
    }

    .nav-links .nav-link::before {
        content: '›';
        font-size: 1.1rem;
        color: var(--arc-amber);
        font-weight: 300;
        transition: transform 0.2s;
    }

    .nav-links .nav-link:hover {
        background: rgba(255,255,255,0.05);
        color: rgba(255,255,255,0.95);
    }

    .nav-links .nav-link:hover::before {
        transform: translateX(3px);
    }

    .nav-links .nav-link:last-child {
        border-bottom: none;
    }

    .nav-links .nav-blog {
        margin-top: 1.5rem;
        margin-left: 1.5rem;
        margin-right: 1.5rem;
        padding: 0.85rem 1rem;
        background: var(--arc-orange);
        color: #fff !important;
        border-radius: var(--radius-sm);
        font-weight: 600;
        font-size: 0.92rem;
        text-align: center;
        border-bottom: none;
        letter-spacing: 0.05em;
        box-shadow: 0 4px 16px rgba(232,93,4,0.35);
    }

    .nav-links .nav-blog::before {
        display: none;
    }

    .nav-links .nav-blog:hover {
        background: var(--accent-hover);
        box-shadow: 0 6px 24px rgba(232,93,4,0.45);
    }

    /* 移动端菜单底部留白 */
    .nav-links {
        padding-bottom: 2rem;
    }

    /* 显示汉堡按钮，隐藏桌面菜单 */
    .nav-toggle { display: flex; }
    .nav-links {
        display: none;
    }
}

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

.hero-bg-video {
    position: absolute;
    inset: 0;
    z-index: 0;
    width: 100vw;
    height: 100%;
}

.hero-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    image-rendering: high-quality;
    image-rendering: -webkit-optimize-contrast;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    z-index: 1;
    background: rgba(10, 8, 5, 0.25);
    width: 100vw;
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    width: 100%;
    max-width: 900px;
    text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.hero-label {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.35em;
    color: var(--arc-amber);
    text-transform: uppercase;
    margin-bottom: 2rem;
    padding: 0.5rem 1.2rem;
    background: rgba(244, 140, 6, 0.15);
    border: 1px solid rgba(244, 140, 6, 0.3);
    border-radius: var(--radius-pill);
    text-shadow: none;
}

.hero-title {
    font-size: clamp(5rem, 15vw, 10rem);
    font-weight: 900;
    letter-spacing: -0.04em;
    color: #ffffff;
    line-height: 1;
    margin-bottom: 2rem;
    text-shadow:
        0 0 30px rgba(255, 255, 255, 0.4),
        0 0 60px rgba(255, 255, 255, 0.2),
        3px 3px 12px rgba(0, 0, 0, 0.5);
}

.hero-slogan {
    font-size: 1.5rem;
    color: rgba(255, 255, 255, 0.95);
    margin-bottom: 3rem;
    font-weight: 400;
    text-shadow: 0 2px 15px rgba(0, 0, 0, 0.4);
}

/* 按钮 */
.btn {
    display: inline-block;
    font-size: 0.9rem;
    font-weight: 600;
    padding: 0.75rem 1.75rem;
    border-radius: var(--radius-sm);
    transition: transform 0.2s, box-shadow 0.2s;
    cursor: pointer;
    text-shadow: none;
}

.btn-primary {
    background: var(--accent);
    color: #fff;
    border: none;
    box-shadow: 0 2px 10px rgba(232, 93, 4, 0.3);
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(232, 93, 4, 0.4);
}

.btn-outline-light {
    background: transparent;
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.4);
    margin-left: 0.75rem;
}

.btn-outline-light:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.6);
    transform: translateY(-2px);
}

.hero-cta {
    display: flex;
    justify-content: center;
    align-items: center;
}

/* ============================================
   移动端响应式（手机）
   ============================================ */
@media (max-width: 768px) {
    :root {
        --container-pad: 1.25rem;
        --nav-height: 52px;
    }

    .nav-inner {
        padding: 0 1.25rem;
    }

    /* 显示汉堡按钮，隐藏桌面菜单 */
    .nav-toggle { display: flex; }
    .nav-links {
        display: none; /* 桌面端隐藏，JS控制显示 */
    }

    /* Hero 全宽 */
    .hero-content {
        padding: 0 1.25rem;
        width: 100%;
        max-width: 100%;
    }

    .hero-title {
        font-size: clamp(2.8rem, 16vw, 4rem);
        margin-bottom: 1.25rem;
    }

    .hero-slogan {
        font-size: 1rem;
        margin-bottom: 2rem;
    }

    .hero-label {
        font-size: 0.65rem;
        padding: 0.4rem 0.9rem;
        margin-bottom: 1.5rem;
    }

    .hero-cta {
        flex-direction: column;
        align-items: center;
        gap: 0.75rem;
    }

    .hero-cta .btn {
        width: 100%;
        max-width: 240px;
        padding: 0.85rem 1.5rem;
        font-size: 0.95rem;
    }

    .hero-cta .btn-outline-light {
        margin-left: 0;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: clamp(2.4rem, 17vw, 3.2rem);
    }

    .hero-cta .btn {
        max-width: 200px;
    }
}

/* ============================================
   桌面端响应式（平板）
   ============================================ */
@media (max-width: 1024px) {
    :root {
        --container-pad: 2rem;
    }

    .hero-title {
        font-size: clamp(4rem, 12vw, 8rem);
    }

    .hero-slogan {
        font-size: 1.4rem;
    }
}