/* ============================================
   觉枫数据 - 全局样式
   风格：简约大气、商务、富有诗意
   ============================================ */

:root {
    /* 主色调 */
    --color-bg: #faf8f4;
    --color-bg-alt: #f3ede3;
    --color-text: #1a1a1a;
    --color-text-soft: #5a5854;
    --color-text-mute: #8a8780;

    /* 品牌色（取自Hero图片） */
    --color-primary: #6b0f0f;       /* 深红 */
    --color-primary-deep: #3d0606;
    --color-gold: #c9a35e;          /* 金 */
    --color-gold-light: #e8c97a;
    --color-gold-bright: #f4d77a;

    /* 边框 / 阴影 */
    --border-light: rgba(26, 26, 26, 0.08);
    --border-gold: rgba(201, 163, 94, 0.3);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 16px 60px rgba(0, 0, 0, 0.12);

    /* 字体（均为 SIL OFL 开源可商用字体，规避版权风险；诗句行楷为豁免项） */
    --font-serif: "Noto Serif SC", "Source Han Serif SC", serif;
    --font-sans: "Noto Sans SC", "Source Han Sans SC", sans-serif;
    --font-en: "Inter", sans-serif;

    /* 容器 */
    --container-max: 1280px;
    --radius: 4px;
    --radius-lg: 8px;

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

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color 0.3s var(--ease);
}

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

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

/* ============================================
   导航栏
   ============================================ */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 1.25rem 0;
    background: rgba(250, 248, 244, 0.85);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid transparent;
    transition: all 0.4s var(--ease);
}

.nav.scrolled {
    padding: 0.75rem 0;
    border-bottom-color: var(--border-light);
    box-shadow: var(--shadow-sm);
}

.nav__inner {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav__brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: var(--font-serif);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-text);
    letter-spacing: 0.05em;
}

.nav__logo-img {
    width: 36px;
    height: 36px;
    display: block;
    object-fit: contain;
    filter: drop-shadow(0 1px 4px rgba(212, 175, 55, 0.25));
}

.nav__brand-en {
    font-family: var(--font-en);
    font-size: 0.7rem;
    color: var(--color-text-mute);
    font-weight: 400;
    letter-spacing: 0.15em;
    margin-left: 0.25rem;
    text-transform: uppercase;
}

.nav__menu {
    display: flex;
    gap: 2.5rem;
    list-style: none;
}

.nav__link {
    font-size: 0.95rem;
    color: var(--color-text-soft);
    position: relative;
    padding: 0.25rem 0;
    transition: color 0.3s var(--ease);
}

.nav__link::after {
    content: "";
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--color-gold);
    transition: width 0.3s var(--ease);
}

.nav__link:hover,
.nav__link.active {
    color: var(--color-text);
}

.nav__link.active::after,
.nav__link:hover::after {
    width: 100%;
}

.nav__cta {
    padding: 0.55rem 1.4rem;
    background: var(--color-text);
    color: var(--color-bg);
    font-size: 0.9rem;
    border-radius: 2px;
    letter-spacing: 0.05em;
    transition: all 0.3s var(--ease);
}

.nav__cta:hover {
    background: var(--color-primary);
    color: var(--color-gold-bright);
    transform: translateY(-1px);
}

.nav__toggle {
    display: none;
    width: 32px;
    height: 32px;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    padding: 0;
}

    .nav__toggle span {
        width: 22px;
        height: 1.5px;
        background: var(--color-text);
        transition: all 0.3s var(--ease);
    }

    /* ========== 科技风导航（与首页一致，全站通用） ========== */
    .nav--tech {
        background: rgba(18, 8, 8, 0.42);
        backdrop-filter: blur(26px) saturate(180%);
        -webkit-backdrop-filter: blur(26px) saturate(180%);
        border-bottom: 1px solid rgba(244, 215, 122, 0.14);
    }

    .nav--tech.scrolled {
        background: rgba(14, 6, 6, 0.74);
        border-bottom-color: rgba(244, 215, 122, 0.26);
        box-shadow: 0 6px 34px rgba(0, 0, 0, 0.3);
    }

    .nav--tech .nav__brand { color: #fff; }
    .nav--tech .nav__brand-en { color: rgba(255, 255, 255, 0.5); }
    .nav--tech .nav__logo {
        background: linear-gradient(135deg, var(--color-gold) 0%, var(--color-gold-bright) 100%);
        color: #2a0808;
        box-shadow: 0 0 16px rgba(244, 215, 122, 0.45);
    }
    .nav--tech .nav__link { color: rgba(255, 255, 255, 0.78); }
    .nav--tech .nav__link:hover,
    .nav--tech .nav__link.active { color: #fff; }
    .nav--tech .nav__link.active::after,
    .nav--tech .nav__link:hover::after {
        background: linear-gradient(90deg, var(--color-gold), var(--color-gold-bright));
        box-shadow: 0 0 8px rgba(244, 215, 122, 0.6);
    }
    .nav--tech .nav__cta {
        background: linear-gradient(135deg, var(--color-gold) 0%, var(--color-gold-bright) 100%);
        color: #2a0808;
        border-radius: 100px;
        font-weight: 600;
        box-shadow: 0 0 16px rgba(244, 215, 122, 0.3);
    }
    .nav--tech .nav__cta:hover {
        background: linear-gradient(135deg, var(--color-gold-bright) 0%, var(--color-gold) 100%);
        box-shadow: 0 0 26px rgba(244, 215, 122, 0.55);
        transform: translateY(-2px);
    }
    .nav--tech .nav__toggle span { background: #fff; }

    /* ============================================
       通用 Section
   ============================================ */
.section {
    padding: 7rem 2rem;
}

.section--dark {
    background: var(--color-text);
    color: var(--color-bg);
}

.section--primary {
    background: var(--color-primary);
    color: var(--color-bg);
}

.section__inner {
    max-width: var(--container-max);
    margin: 0 auto;
}

.section__eyebrow {
    display: inline-block;
    font-family: var(--font-en);
    font-size: 0.75rem;
    letter-spacing: 0.3em;
    color: var(--color-gold);
    text-transform: uppercase;
    margin-bottom: 1rem;
    font-weight: 500;
}

.section--dark .section__eyebrow,
.section--primary .section__eyebrow {
    color: var(--color-gold-bright);
}

.section__title {
    font-family: var(--font-serif);
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 500;
    line-height: 1.3;
    margin-bottom: 1.5rem;
    letter-spacing: 0.02em;
}

.section__title-en {
    font-family: var(--font-en);
    font-size: 0.9rem;
    color: var(--color-text-mute);
    font-weight: 400;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    margin-bottom: 0.5rem;
}

.section--dark .section__title-en,
.section--primary .section__title-en {
    color: rgba(255, 255, 255, 0.4);
}

.section__lead {
    font-size: 1.05rem;
    color: var(--color-text-soft);
    max-width: 720px;
    line-height: 1.8;
}

.section--dark .section__lead,
.section--primary .section__lead {
    color: rgba(255, 255, 255, 0.7);
}

.section__header {
    text-align: center;
    margin-bottom: 4rem;
}

.section__header .section__lead {
    margin: 0 auto;
}

/* ============================================
   按钮
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.95rem 2rem;
    font-size: 0.95rem;
    border-radius: 2px;
    transition: all 0.4s var(--ease);
    cursor: pointer;
    letter-spacing: 0.05em;
    font-weight: 500;
    border: 1px solid transparent;
}

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

.btn--primary:hover {
    background: var(--color-primary-deep);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(107, 15, 15, 0.25);
}

.btn--ghost {
    background: transparent;
    color: var(--color-text);
    border-color: var(--border-light);
}

.btn--ghost:hover {
    background: var(--color-text);
    color: var(--color-bg);
    border-color: var(--color-text);
}

.btn--gold {
    background: var(--color-gold);
    color: var(--color-text);
}

.btn--gold:hover {
    background: var(--color-gold-light);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(201, 163, 94, 0.35);
}

.btn--light {
    background: var(--color-bg);
    color: var(--color-text);
}

.btn--light:hover {
    background: var(--color-gold-bright);
    transform: translateY(-2px);
}

.btn__arrow {
    transition: transform 0.3s var(--ease);
}

.btn:hover .btn__arrow {
    transform: translateX(4px);
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: #0f0a08;
    color: rgba(255, 255, 255, 0.6);
    padding: 5rem 2rem 2rem;
}

.footer__inner {
    max-width: var(--container-max);
    margin: 0 auto;
}

.footer__top {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
    gap: 4rem;
    padding-bottom: 3rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.footer__brand {
    font-family: var(--font-serif);
    font-size: 1.4rem;
    color: var(--color-gold-bright);
    margin-bottom: 1rem;
    letter-spacing: 0.1em;
}

.footer__desc {
    font-size: 0.9rem;
    line-height: 1.8;
    max-width: 320px;
}

.footer__col h4 {
    font-family: var(--font-serif);
    font-size: 0.95rem;
    color: var(--color-bg);
    margin-bottom: 1.25rem;
    font-weight: 500;
    letter-spacing: 0.1em;
}

.footer__col ul {
    list-style: none;
}

.footer__col li {
    margin-bottom: 0.75rem;
}

.footer__col a {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.55);
    transition: color 0.3s var(--ease);
}

.footer__col a:hover {
    color: var(--color-gold-bright);
}

.footer__contact-item {
    display: flex;
    gap: 0.5rem;
    align-items: flex-start;
    margin-bottom: 0.75rem;
    font-size: 0.9rem;
    line-height: 1.6;
}

.footer__contact-item svg {
    flex-shrink: 0;
    margin-top: 2px;
    color: var(--color-gold);
}

.footer__bottom {
    padding-top: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.4);
}

.footer__legal {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem 2rem;
}

.footer__legal a:hover {
    color: var(--color-gold-bright);
}

/* 双备案号（ICP + 公安）与图标 */
.footer__beian {
    display: inline-flex;
    align-items: center;
    gap: 1.25rem;
    flex-wrap: wrap;
}

.footer__beian-item {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    color: inherit;
    text-decoration: none;
    white-space: nowrap;
}

.footer__beian-item:hover {
    color: var(--color-gold-bright);
}

.footer__beian-icon {
    width: 14px;
    height: 14px;
    flex-shrink: 0;
    color: var(--color-gold);
}

.footer__beian-badge {
    width: 11px;
    height: auto;
    flex-shrink: 0;
}

/* ============================================
   响应式
   ============================================ */
@media (max-width: 960px) {
    .nav__menu {
        display: none;
    }
    .nav__toggle {
        display: flex;
    }
    .footer__top {
        grid-template-columns: 1fr 1fr;
        gap: 2.5rem;
    }
    .section {
        padding: 5rem 1.5rem;
    }
}

@media (max-width: 600px) {
    .nav__inner {
        padding: 0 1.25rem;
    }
    .nav__cta {
        display: none;
    }
    .footer__top {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    .footer__bottom {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}

/* ============================================
   工具类
   ============================================ */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

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