/* ===================================================================
   香港时光药业有限公司 - 复古纸张风格样式表
   设计：纸张米色 + 深棕 + 暗红，纸张纹理，墨水晕染，复古印章
   =================================================================== */

/* ---------- 全局重置与变量 ---------- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 主色调：纸张米色系 */
    --paper-light: #F5E6D3;
    --paper-base: #EDE0D4;
    --paper-dark: #E0D0BC;
    /* 深棕色系 */
    --brown-dark: #5C4033;
    --brown-mid: #8B4513;
    --brown-light: #A0522D;
    /* 暗红色系（印章/强调） */
    --ink-red: #8B0000;
    --ink-red-soft: #A52A2A;
    /* 文字色 */
    --text-main: #3E2723;
    --text-muted: #6D4C41;
    /* 纸张纹理叠加层 */
    --paper-texture: rgba(139, 69, 19, 0.04);
    /* 字体 */
    --font-serif: 'Crimson Text', 'Noto Serif SC', Georgia, serif;
    --font-cn: 'Noto Serif SC', 'Crimson Text', serif;
    /* 阴影 */
    --shadow-soft: 0 4px 20px rgba(92, 64, 51, 0.15);
    --shadow-paper: 0 2px 12px rgba(92, 64, 51, 0.2);
}

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

body {
    font-family: var(--font-cn);
    color: var(--text-main);
    line-height: 1.8;
    /* 纸张纹理背景：多层径向渐变模拟纸纤维与做旧斑点 */
    background-color: var(--paper-light);
    background-image:
        radial-gradient(circle at 20% 30%, var(--paper-texture) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, var(--paper-texture) 0%, transparent 50%),
        radial-gradient(circle at 50% 50%, rgba(139, 69, 19, 0.03) 0%, transparent 70%),
        repeating-linear-gradient(
            45deg,
            transparent 0px,
            transparent 2px,
            rgba(139, 69, 19, 0.015) 2px,
            rgba(139, 69, 19, 0.015) 4px
        );
    overflow-x: hidden;
}

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

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

/* ---------- 通用容器 ---------- */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.container-narrow {
    max-width: 800px;
}

.section {
    padding: 80px 0;
    position: relative;
}

/* 交替段落背景：模拟纸张分层 */
.section:nth-of-type(even) {
    background-color: var(--paper-base);
    background-image:
        radial-gradient(circle at 30% 40%, rgba(139, 69, 19, 0.05) 0%, transparent 60%),
        repeating-linear-gradient(
            -45deg,
            transparent 0px,
            transparent 3px,
            rgba(139, 69, 19, 0.02) 3px,
            rgba(139, 69, 19, 0.02) 6px
        );
}

/* ---------- 模块标题区 ---------- */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-eyebrow {
    display: block;
    font-family: var(--font-serif);
    font-style: italic;
    font-size: 1rem;
    color: var(--brown-light);
    letter-spacing: 2px;
    margin-bottom: 8px;
    text-transform: uppercase;
}

.section-title {
    font-family: var(--font-cn);
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--brown-dark);
    margin-bottom: 12px;
    letter-spacing: 4px;
}

.section-divider {
    display: inline-block;
    width: 60px;
    height: 2px;
    background: linear-gradient(to right, transparent, var(--brown-mid), transparent);
    position: relative;
}

.section-divider::before,
.section-divider::after {
    content: '◆';
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    font-size: 0.6rem;
    color: var(--brown-mid);
}

.section-divider::before { left: -16px; }
.section-divider::after { right: -16px; }

/* ===================================================================
   模块1：头部 + 导航栏
   =================================================================== */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: rgba(245, 230, 211, 0.95);
    backdrop-filter: blur(6px);
    border-bottom: 1px solid rgba(92, 64, 51, 0.2);
    box-shadow: 0 2px 12px rgba(92, 64, 51, 0.1);
    transition: background-color 0.3s ease;
}

.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 12px 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* logo 印章风格 */
.logo {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
}

.logo-stamp {
    font-family: var(--font-cn);
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--ink-red);
    letter-spacing: 3px;
    /* 模拟印章盖印的粗糙质感 */
    text-shadow: 1px 1px 0 rgba(139, 0, 0, 0.3);
}

.logo-sub {
    font-family: var(--font-serif);
    font-style: italic;
    font-size: 0.7rem;
    color: var(--brown-light);
    letter-spacing: 1px;
    margin-top: 2px;
}

/* 导航链接 */
.nav-links ul {
    display: flex;
    list-style: none;
    gap: 28px;
}

.nav-links a {
    font-family: var(--font-cn);
    font-size: 0.95rem;
    color: var(--brown-dark);
    font-weight: 500;
    position: relative;
    padding: 4px 0;
}

/* 墨水晕染 hover 效果 */
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--ink-red);
    transition: width 0.4s ease, left 0.4s ease;
}

.nav-links a:hover {
    color: var(--ink-red);
}

.nav-links a:hover::after {
    width: 100%;
    left: 0;
}

/* 汉堡菜单按钮 */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 28px;
    height: 22px;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 1001;
}

.menu-toggle span {
    display: block;
    height: 3px;
    width: 100%;
    background: var(--brown-dark);
    border-radius: 2px;
    transition: all 0.3s ease;
}

.menu-toggle.active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
}
.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}
.menu-toggle.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* ===================================================================
   模块2：全屏轮播图（翻页滑动式）
   =================================================================== */
.hero-carousel {
    position: relative;
    width: 100%;
    height: 100vh;
    min-height: 600px;
    overflow: hidden;
    margin-top: 0;
}

.carousel-track {
    position: relative;
    width: 100%;
    height: 100%;
}

.carousel-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    opacity: 0;
    /* 翻页式转场：缩放 + 旋转模拟翻页 */
    transform: perspective(1500px) rotateY(90deg) scale(0.95);
    transform-origin: left center;
    transition: opacity 0.8s ease, transform 1s cubic-bezier(0.65, 0, 0.35, 1);
}

.carousel-slide.active {
    opacity: 1;
    transform: perspective(1500px) rotateY(0deg) scale(1);
}

/* 轮播文字遮罩：模拟纸张做旧 */
.slide-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 60px 40px;
    background: linear-gradient(to top, rgba(62, 39, 35, 0.85) 0%, rgba(92, 64, 51, 0.4) 60%, transparent 100%);
    color: var(--paper-light);
}

.slide-eyebrow {
    font-family: var(--font-serif);
    font-style: italic;
    font-size: 1.1rem;
    color: var(--paper-dark);
    letter-spacing: 2px;
    margin-bottom: 10px;
    opacity: 0.9;
}

.slide-title {
    font-family: var(--font-cn);
    font-size: 3rem;
    font-weight: 700;
    letter-spacing: 6px;
    margin-bottom: 14px;
    text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.5);
}

.slide-desc {
    font-size: 1.05rem;
    letter-spacing: 1px;
    opacity: 0.85;
    max-width: 600px;
}

/* 轮播控制按钮 */
.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: rgba(245, 230, 211, 0.8);
    border: 1px solid var(--brown-mid);
    color: var(--brown-dark);
    font-size: 2rem;
    cursor: pointer;
    z-index: 10;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
}

.carousel-btn:hover {
    background: var(--paper-light);
    color: var(--ink-red);
    box-shadow: var(--shadow-soft);
}

.carousel-prev { left: 25px; }
.carousel-next { right: 25px; }

/* 轮播指示器 */
.carousel-indicators {
    position: absolute;
    bottom: 25px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
    z-index: 10;
}

.carousel-indicators button {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(245, 230, 211, 0.5);
    border: 1px solid var(--brown-dark);
    cursor: pointer;
    transition: all 0.3s ease;
    padding: 0;
}

.carousel-indicators button.active {
    background: var(--ink-red);
    border-color: var(--ink-red);
    transform: scale(1.3);
}

/* ===================================================================
   模块3：关于我们
   =================================================================== */
.about-grid {
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: 50px;
    align-items: center;
    margin-bottom: 60px;
}

.about-text p {
    font-size: 1.05rem;
    color: var(--text-main);
    margin-bottom: 20px;
    text-indent: 2em;
    /* 文字略带做旧效果 */
    text-shadow: 0 0 0.5px rgba(92, 64, 51, 0.1);
}

.about-image {
    position: relative;
    box-shadow: var(--shadow-paper);
    /* 图片做旧：sepia 滤镜 */
}

.about-image img {
    filter: sepia(0.3) contrast(0.95);
    border: 8px solid var(--paper-light);
    box-shadow: inset 0 0 30px rgba(92, 64, 51, 0.2);
}

/* 纸张折角效果 */
.paper-fold {
    position: absolute;
    top: 0;
    right: 0;
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 0 40px 40px 0;
    border-color: transparent var(--paper-base) transparent transparent;
    box-shadow: -2px 2px 4px rgba(92, 64, 51, 0.2);
    transition: border-width 0.4s ease;
}

.about-image:hover .paper-fold {
    border-width: 0 55px 55px 0;
}

/* 统计数据：印章风格 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.stat-item {
    text-align: center;
    padding: 30px 15px;
    background-color: var(--paper-light);
    border: 1px solid rgba(139, 69, 19, 0.2);
    /* 模拟纸张边缘做旧 */
    box-shadow: var(--shadow-soft), inset 0 0 20px rgba(139, 69, 19, 0.05);
    position: relative;
}

.stat-item::before {
    content: '';
    position: absolute;
    inset: 6px;
    border: 1px dashed rgba(139, 69, 19, 0.2);
    pointer-events: none;
}

.stat-number {
    display: block;
    font-family: var(--font-serif);
    font-size: 2.8rem;
    font-weight: 700;
    color: var(--ink-red);
    line-height: 1;
    margin-bottom: 8px;
}

.stat-unit {
    font-size: 1rem;
    color: var(--brown-mid);
    margin-left: 2px;
}

.stat-label {
    display: block;
    font-family: var(--font-cn);
    font-size: 0.95rem;
    color: var(--brown-dark);
    letter-spacing: 2px;
}

/* ===================================================================
   模块4：服务介绍（滑入式面板）
   =================================================================== */
.services-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.service-card {
    padding: 40px 35px;
    background-color: var(--paper-light);
    border: 1px solid rgba(139, 69, 19, 0.25);
    position: relative;
    transition: transform 0.4s ease, box-shadow 0.4s ease;
    /* 纸张做旧阴影 */
    box-shadow: var(--shadow-paper);
}

.service-card::before {
    content: '';
    position: absolute;
    inset: 8px;
    border: 1px solid rgba(139, 69, 19, 0.15);
    pointer-events: none;
}

.service-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 8px 28px rgba(92, 64, 51, 0.25);
}

.service-number {
    font-family: var(--font-cn);
    font-size: 1.6rem;
    color: var(--ink-red);
    font-weight: 700;
    margin-bottom: 14px;
    display: inline-block;
    /* 模拟毛笔字 */
    text-shadow: 1px 1px 2px rgba(139, 0, 0, 0.3);
}

.service-title {
    font-family: var(--font-cn);
    font-size: 1.5rem;
    color: var(--brown-dark);
    margin-bottom: 14px;
    letter-spacing: 3px;
    font-weight: 600;
}

.service-desc {
    color: var(--text-muted);
    font-size: 0.98rem;
    line-height: 1.9;
}

/* 滑入式面板初始状态（由 JS 触发显示） */
[data-slide-from="left"] {
    opacity: 0;
    transform: translateX(-60px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

[data-slide-from="right"] {
    opacity: 0;
    transform: translateX(60px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

[data-slide-from="left"].in-view,
[data-slide-from="right"].in-view {
    opacity: 1;
    transform: translateX(0);
}

/* ===================================================================
   模块5：客户案例（滑动展示）
   =================================================================== */
.cases-slider {
    overflow: hidden;
    padding: 10px 0;
}

.cases-track {
    display: flex;
    gap: 24px;
    transition: transform 0.6s cubic-bezier(0.65, 0, 0.35, 1);
    will-change: transform;
}

.case-card {
    flex: 0 0 calc(25% - 18px);
    min-width: 0;
    background-color: var(--paper-light);
    border: 1px solid rgba(139, 69, 19, 0.2);
    box-shadow: var(--shadow-paper);
    overflow: hidden;
    transition: transform 0.4s ease;
}

.case-card:hover {
    transform: translateY(-5px);
}

.case-image img {
    width: 100%;
    aspect-ratio: 1 / 1;
    object-fit: cover;
    filter: sepia(0.4) contrast(0.9);
    transition: filter 0.4s ease;
}

.case-card:hover .case-image img {
    filter: sepia(0.2) contrast(1);
}

.case-info {
    padding: 20px;
}

.case-name {
    font-family: var(--font-cn);
    font-size: 1.15rem;
    color: var(--brown-dark);
    margin-bottom: 10px;
    font-weight: 600;
}

.case-quote {
    font-size: 0.9rem;
    color: var(--text-muted);
    font-style: italic;
    line-height: 1.7;
}

.slider-controls {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-top: 30px;
}

.slider-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--paper-light);
    border: 1px solid var(--brown-mid);
    color: var(--brown-dark);
    font-size: 1.6rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
}

.slider-btn:hover {
    background: var(--ink-red);
    border-color: var(--ink-red);
    color: var(--paper-light);
}

/* ===================================================================
   模块6：新闻资讯
   =================================================================== */
.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.news-card {
    padding: 30px;
    background-color: var(--paper-light);
    border: 1px solid rgba(139, 69, 19, 0.2);
    box-shadow: var(--shadow-paper);
    position: relative;
    transition: transform 0.4s ease, box-shadow 0.4s ease;
}

/* 新闻卡片右上角折角 */
.news-card::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 0 25px 25px 0;
    border-color: transparent var(--paper-base) transparent transparent;
    transition: border-width 0.3s ease;
}

.news-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 24px rgba(92, 64, 51, 0.2);
}

.news-card:hover::after {
    border-width: 0 35px 35px 0;
}

.news-date {
    display: inline-block;
    margin-bottom: 16px;
    padding: 6px 14px;
    background-color: var(--brown-dark);
    color: var(--paper-light);
    text-align: center;
    line-height: 1.3;
}

.news-day {
    display: block;
    font-family: var(--font-serif);
    font-size: 1.4rem;
    font-weight: 700;
}

.news-month {
    display: block;
    font-size: 0.7rem;
    letter-spacing: 1px;
}

.news-title {
    font-family: var(--font-cn);
    font-size: 1.15rem;
    color: var(--brown-dark);
    margin-bottom: 12px;
    font-weight: 600;
    line-height: 1.5;
}

.news-excerpt {
    font-size: 0.92rem;
    color: var(--text-muted);
    line-height: 1.8;
    margin-bottom: 16px;
}

.news-link {
    font-family: var(--font-serif);
    font-style: italic;
    font-size: 0.95rem;
    color: var(--ink-red);
    border-bottom: 1px solid transparent;
    transition: border-color 0.3s ease;
}

.news-link:hover {
    border-bottom-color: var(--ink-red);
}

/* ===================================================================
   模块7：常见问题FAQ（手风琴）
   =================================================================== */
.faq-list {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.faq-item {
    background-color: var(--paper-light);
    border: 1px solid rgba(139, 69, 19, 0.25);
    overflow: hidden;
    transition: box-shadow 0.3s ease;
}

.faq-item:hover {
    box-shadow: var(--shadow-soft);
}

.faq-question {
    width: 100%;
    padding: 20px 24px;
    background: transparent;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-family: var(--font-cn);
    font-size: 1.05rem;
    color: var(--brown-dark);
    text-align: left;
    font-weight: 600;
    letter-spacing: 1px;
}

.faq-q-text {
    flex: 1;
    padding-right: 16px;
}

.faq-icon {
    font-size: 1.5rem;
    color: var(--ink-red);
    transition: transform 0.4s ease;
    flex-shrink: 0;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s ease, padding 0.5s ease;
    padding: 0 24px;
}

.faq-item.active .faq-answer {
    max-height: 300px;
    padding: 0 24px 20px;
}

.faq-answer p {
    color: var(--text-muted);
    font-size: 0.98rem;
    line-height: 1.9;
    border-top: 1px dashed rgba(139, 69, 19, 0.3);
    padding-top: 14px;
}

/* ===================================================================
   模块8：联系我们
   =================================================================== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1.3fr;
    gap: 50px;
    align-items: start;
}

/* 联系信息 */
.contact-info {
    padding: 35px 30px;
    background-color: var(--paper-light);
    border: 1px solid rgba(139, 69, 19, 0.2);
    box-shadow: var(--shadow-paper);
    position: relative;
}

.contact-subtitle {
    font-family: var(--font-cn);
    font-size: 1.4rem;
    color: var(--brown-dark);
    margin-bottom: 6px;
    font-weight: 700;
    letter-spacing: 2px;
}

.contact-en {
    font-family: var(--font-serif);
    font-style: italic;
    font-size: 0.9rem;
    color: var(--brown-light);
    margin-bottom: 24px;
}

.contact-details {
    list-style: none;
}

.contact-details li {
    padding: 10px 0;
    border-bottom: 1px dashed rgba(139, 69, 19, 0.2);
    color: var(--text-main);
    font-size: 0.98rem;
}

.contact-details li:last-child {
    border-bottom: none;
}

.contact-details strong {
    color: var(--brown-dark);
    font-weight: 600;
}

/* 复古印章装饰 */
.contact-stamp {
    position: absolute;
    bottom: 25px;
    right: 25px;
    width: 90px;
    height: 90px;
    border: 2px solid var(--ink-red);
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--ink-red);
    transform: rotate(-12deg);
    opacity: 0.7;
    /* 模拟印章盖印不均匀效果 */
    box-shadow: inset 0 0 4px rgba(139, 0, 0, 0.3);
    background: radial-gradient(circle, rgba(139, 0, 0, 0.05) 0%, transparent 70%);
}

.contact-stamp span {
    font-family: var(--font-serif);
    font-size: 0.65rem;
    letter-spacing: 1px;
}

.contact-stamp strong {
    font-family: var(--font-serif);
    font-size: 1.5rem;
    font-weight: 700;
    margin: 2px 0;
}

/* 复古风格表单 */
.contact-form {
    padding: 35px 30px;
    background-color: var(--paper-light);
    border: 1px solid rgba(139, 69, 19, 0.2);
    box-shadow: var(--shadow-paper);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-family: var(--font-cn);
    font-size: 0.95rem;
    color: var(--brown-dark);
    margin-bottom: 8px;
    font-weight: 600;
    letter-spacing: 1px;
}

.required {
    color: var(--ink-red);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 14px;
    font-family: var(--font-cn);
    font-size: 0.98rem;
    color: var(--text-main);
    background-color: rgba(237, 224, 212, 0.5);
    border: 1px solid rgba(139, 69, 19, 0.3);
    border-radius: 2px;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
    resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--brown-mid);
    box-shadow: 0 0 0 3px rgba(139, 69, 19, 0.1);
    background-color: var(--paper-light);
}

/* 表单错误提示 */
.form-error {
    display: block;
    color: var(--ink-red);
    font-size: 0.85rem;
    margin-top: 5px;
    min-height: 1em;
    font-family: var(--font-cn);
}

.form-group input.invalid,
.form-group textarea.invalid {
    border-color: var(--ink-red);
    background-color: rgba(139, 0, 0, 0.03);
}

/* 提交按钮：墨水晕染 hover */
.form-submit {
    width: 100%;
    padding: 14px;
    font-family: var(--font-cn);
    font-size: 1.05rem;
    letter-spacing: 4px;
    color: var(--paper-light);
    background-color: var(--brown-dark);
    border: none;
    border-radius: 2px;
    cursor: pointer;
    transition: background-color 0.4s ease, box-shadow 0.4s ease;
    position: relative;
    overflow: hidden;
}

/* 墨水晕染扩散效果 */
.form-submit::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: var(--ink-red);
    transform: translate(-50%, -50%);
    transition: width 0.6s ease, height 0.6s ease;
}

.form-submit:hover::before {
    width: 400px;
    height: 400px;
}

.form-submit span,
.form-submit {
    position: relative;
    z-index: 1;
}

.form-success {
    display: none;
    margin-top: 16px;
    padding: 12px;
    background-color: rgba(139, 69, 19, 0.1);
    border: 1px solid var(--brown-mid);
    color: var(--brown-dark);
    text-align: center;
    font-size: 0.95rem;
    border-radius: 2px;
}

.form-success.show {
    display: block;
}

/* ===================================================================
   模块9：页脚 + 友情链接
   =================================================================== */
.site-footer {
    background-color: var(--brown-dark);
    color: var(--paper-light);
    padding: 50px 0 25px;
    /* 纸张纹理叠加 */
    background-image:
        radial-gradient(circle at 20% 50%, rgba(245, 230, 211, 0.05) 0%, transparent 50%),
        repeating-linear-gradient(
            45deg,
            transparent 0px,
            transparent 3px,
            rgba(245, 230, 211, 0.02) 3px,
            rgba(245, 230, 211, 0.02) 6px
        );
}

.footer-top {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 40px;
    padding-bottom: 30px;
    border-bottom: 1px solid rgba(245, 230, 211, 0.2);
}

.footer-brand {
    flex: 1;
    min-width: 250px;
}

.footer-logo {
    font-family: var(--font-cn);
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--paper-light);
    letter-spacing: 3px;
    display: block;
    margin-bottom: 8px;
}

.footer-tagline {
    font-family: var(--font-serif);
    font-style: italic;
    font-size: 0.9rem;
    color: var(--paper-dark);
    opacity: 0.8;
}

.footer-links-block {
    flex: 1;
    min-width: 250px;
}

.footer-heading {
    font-family: var(--font-cn);
    font-size: 1.1rem;
    color: var(--paper-light);
    margin-bottom: 16px;
    letter-spacing: 2px;
    font-weight: 600;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    color: var(--paper-dark);
    font-size: 0.92rem;
    transition: color 0.3s ease;
    position: relative;
    padding-left: 14px;
}

.footer-links a::before {
    content: '◆';
    position: absolute;
    left: 0;
    font-size: 0.55rem;
    color: var(--ink-red-soft);
    top: 4px;
}

.footer-links a:hover {
    color: var(--paper-light);
}

.footer-bottom {
    padding-top: 25px;
    text-align: center;
    font-size: 0.85rem;
    color: var(--paper-dark);
    opacity: 0.7;
    line-height: 1.8;
}

/* ---------- 返回顶部按钮 ---------- */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background-color: var(--brown-dark);
    color: var(--paper-light);
    border: 2px solid var(--paper-light);
    font-size: 1.5rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s ease;
    z-index: 999;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background-color: var(--ink-red);
    border-color: var(--ink-red);
    transform: translateY(-4px);
}

/* ===================================================================
   IntersectionObserver 滚动动画
   =================================================================== */
[data-animate] {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

[data-animate].in-view {
    opacity: 1;
    transform: translateY(0);
}

/* ===================================================================
   响应式设计（移动优先）
   =================================================================== */

/* 平板（≤992px） */
@media (max-width: 992px) {
    .section { padding: 60px 0; }

    .section-title { font-size: 1.9rem; }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .about-image { order: -1; }

    .services-grid {
        grid-template-columns: 1fr;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .news-grid {
        grid-template-columns: 1fr;
    }

    .contact-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .case-card {
        flex: 0 0 calc(50% - 12px);
    }

    .slide-title { font-size: 2.3rem; }
}

/* 移动端（≤768px） */
@media (max-width: 768px) {
    .section { padding: 50px 0; }

    /* 汉堡菜单显示 */
    .menu-toggle {
        display: flex;
    }

    /* 移动端导航：抽屉式 */
    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 320px;
        height: 100vh;
        background-color: var(--paper-light);
        border-left: 1px solid var(--brown-mid);
        box-shadow: -4px 0 20px rgba(92, 64, 51, 0.3);
        transition: right 0.4s cubic-bezier(0.65, 0, 0.35, 1);
        padding: 80px 30px 30px;
        overflow-y: auto;
    }

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

    .nav-links ul {
        flex-direction: column;
        gap: 0;
    }

    .nav-links li {
        border-bottom: 1px dashed rgba(139, 69, 19, 0.2);
    }

    .nav-links a {
        display: block;
        padding: 16px 0;
        font-size: 1.05rem;
    }

    /* 轮播图移动端调整 */
    .hero-carousel {
        height: 80vh;
        min-height: 500px;
    }

    .slide-overlay {
        padding: 40px 20px;
    }

    .slide-title {
        font-size: 1.8rem;
        letter-spacing: 3px;
    }

    .slide-desc {
        font-size: 0.9rem;
    }

    .carousel-btn {
        width: 40px;
        height: 40px;
        font-size: 1.6rem;
    }

    .carousel-prev { left: 10px; }
    .carousel-next { right: 10px; }

    .section-title {
        font-size: 1.7rem;
        letter-spacing: 3px;
    }

    .stats-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }

    .stat-number { font-size: 2.3rem; }

    .case-card {
        flex: 0 0 calc(80% - 12px);
    }

    .contact-stamp {
        width: 70px;
        height: 70px;
    }

    .contact-stamp strong { font-size: 1.2rem; }

    .back-to-top {
        width: 42px;
        height: 42px;
        bottom: 20px;
        right: 20px;
    }
}

/* 小屏手机（≤480px） */
@media (max-width: 480px) {
    .container { padding: 0 16px; }

    .logo-stamp { font-size: 1.25rem; letter-spacing: 2px; }
    .logo-sub { font-size: 0.6rem; }

    .slide-title { font-size: 1.5rem; }

    .service-card,
    .news-card,
    .contact-form,
    .contact-info {
        padding: 25px 20px;
    }

    .footer-top {
        flex-direction: column;
        gap: 30px;
    }
}