/* styles.css */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Playfair+Display:wght@600;700&family=Noto+Serif+SC:wght@600;700&family=Noto+Sans+SC:wght@400;500&display=swap');

:root {
    --htic-red: #9A1D1F;
    --htic-bronze: #C96619;
    --htic-gold: #F8AF12;
    --htic-ink: #0f172a;
    --htic-cream: #f8fafc;
    --htic-gradient: linear-gradient(135deg, var(--htic-red) 0%, var(--htic-bronze) 54%, var(--htic-gold) 100%);
}

html, body {
    overflow-x: hidden;
    scroll-behavior: smooth;
    /* 英文优先，中文回退到系统级优雅黑体 */
    font-family: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

h1, h2, h3, h4, h5, h6, .font-serif {
    /* 标题使用英文衬线体，中文回退到思源宋体，凸显高级感 */
    font-family: 'Playfair Display', 'Noto Serif SC', 'SimSun', serif;
}

.bg-gradient-htic {
    background-image: var(--htic-gradient);
}

/* 统一导航栏滚动状态样式 */
.site-header {
    background: linear-gradient(180deg, rgba(15, 23, 42, 0.74), rgba(15, 23, 42, 0));
}

.header-scrolled {
    background-color: #ffffff !important;
    background-image: none !important;
    box-shadow: 0 14px 34px rgba(15, 23, 42, 0.08);
    padding-top: 1rem !important;
    padding-bottom: 1rem !important;
    border-bottom: 1px solid rgba(226, 232, 240, 0.9);
}

.site-logo {
    text-decoration: none;
}

.site-logo .logo-text {
    letter-spacing: -0.04em;
}

.site-logo .logo-desc {
    border-color: rgba(255, 255, 255, 0.32);
}

.site-logo .logo-desc span {
    letter-spacing: 0.01em;
}

.site-nav-link {
    position: relative;
    color: rgba(255, 255, 255, 0.88);
    font-size: 0.92rem;
    font-weight: 600;
    letter-spacing: 0.01em;
    transition: color 0.25s ease;
}

.site-nav-link::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: -0.55rem;
    height: 2px;
    background: var(--htic-gradient);
    opacity: 0;
    transform: scaleX(0.55);
    transform-origin: center;
    transition: opacity 0.25s ease, transform 0.25s ease;
}

.site-nav-link:hover,
.site-nav-link.is-active {
    color: var(--htic-gold);
}

.site-nav-link:hover::after,
.site-nav-link.is-active::after {
    opacity: 1;
    transform: scaleX(1);
}

.site-language-switch {
    display: inline-flex;
    align-items: center;
    gap: 1.05rem;
    padding: 0;
    border: 0;
    background: transparent;
}

.site-language-switch .lang-btn,
.site-mobile-actions .lang-btn {
    min-width: auto;
    height: auto;
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.94rem;
    font-weight: 700;
    letter-spacing: 0.02em;
    transition: color 0.25s ease, opacity 0.25s ease;
}

.site-language-switch .lang-btn:hover,
.site-language-switch .lang-btn.is-active {
    color: var(--htic-gold);
}

.site-contact-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 3.1rem;
    padding: 0 1.5rem;
    color: #fff;
    font-weight: 800;
    font-size: 1.04rem;
    background: linear-gradient(135deg, #a61f20 0%, #ce6418 58%, #f7ae12 100%);
    border: 0;
    border-radius: 2px;
    box-shadow: 0 10px 22px rgba(154, 29, 31, 0.18);
    transition: transform 0.25s ease, box-shadow 0.25s ease, filter 0.25s ease;
}

.site-contact-btn:hover {
    transform: translateY(-1px);
    filter: saturate(1.03);
    box-shadow: 0 14px 28px rgba(154, 29, 31, 0.24);
}

.site-menu-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.6rem;
    height: 2.6rem;
    color: #fff;
    background: rgba(255, 255, 255, 0.12);
    border: 1px solid rgba(255, 255, 255, 0.22);
    backdrop-filter: blur(12px);
    transition: background 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}

.site-mobile-panel {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    border-top: 1px solid rgba(226, 232, 240, 0.9);
    box-shadow: 0 24px 44px rgba(15, 23, 42, 0.14);
}

.mobile-nav-link {
    display: block;
    padding: 0.85rem 0.9rem;
    color: #1e293b;
    font-weight: 700;
    border-left: 3px solid transparent;
    transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.mobile-nav-link:hover,
.mobile-nav-link.is-active {
    color: var(--htic-red);
    background: #f8fafc;
    border-left-color: var(--htic-bronze);
}

.site-mobile-actions {
    display: flex;
    align-items: center;
    gap: 1.15rem;
    margin-top: 0.75rem;
    padding: 1rem 0.9rem 0;
    border-top: 1px solid #e2e8f0;
}

.site-mobile-actions .lang-btn {
    color: #475569;
    border: 0;
    font-size: 0.96rem;
}

.site-mobile-actions .lang-btn:hover,
.site-mobile-actions .lang-btn.is-active {
    color: var(--htic-red);
}

.site-mobile-contact {
    display: flex;
    justify-content: center;
    margin: 0.9rem 0.9rem 0;
    padding: 0.82rem 1rem;
    color: #fff;
    font-weight: 800;
    background: var(--htic-gradient);
    border-radius: 2px;
}

.header-scrolled .logo-text { color: #0f172a; }
.header-scrolled .logo-desc p,
.header-scrolled .logo-desc span { color: #475569; }
.header-scrolled .border-l { border-color: #cbd5e1; }
.header-scrolled .nav-link { color: #334155; }
.header-scrolled .nav-link:hover { color: #9A1D1F; }
.header-scrolled .site-nav-link.is-active { color: #9A1D1F; }
.header-scrolled .site-language-switch {
    border-color: transparent;
    background: transparent;
}
.header-scrolled .site-language-switch .lang-btn {
    color: #475569;
}
.header-scrolled .site-language-switch .lang-btn:hover,
.header-scrolled .site-language-switch .lang-btn.is-active {
    color: var(--htic-red);
}
.header-scrolled .site-menu-btn {
    color: #0f172a;
    background: #f8fafc;
    border-color: #e2e8f0;
}

.site-footer {
    color: rgba(255, 255, 255, 0.76);
    background:
        linear-gradient(145deg, rgba(154, 29, 31, 0.16), rgba(15, 23, 42, 0) 36%),
        radial-gradient(circle at 88% 12%, rgba(248, 175, 18, 0.12), transparent 30%),
        #0f172a;
    border-top: 1px solid rgba(248, 175, 18, 0.18);
}

.site-footer-rule {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--htic-gradient);
}

.site-footer-title {
    margin-bottom: 1.25rem;
    color: #fff;
    font-size: 0.78rem;
    font-weight: 800;
    letter-spacing: 0.16em;
    text-transform: uppercase;
}

.site-footer-list {
    display: grid;
    gap: 0.75rem;
}

.site-footer-list a,
.site-footer-bottom a,
.site-footer-contact {
    color: rgba(255, 255, 255, 0.62);
    transition: color 0.22s ease;
}

.site-footer-list a:hover,
.site-footer-bottom a:hover,
.site-footer-contact:hover {
    color: var(--htic-gold);
}

.site-footer-contact {
    display: inline-flex;
    align-items: center;
    gap: 0.7rem;
}

.site-footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding: 1.5rem 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.42);
    font-size: 0.875rem;
}

::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: #f1f1f1; }
::-webkit-scrollbar-thumb { background: #C96619; border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #9A1D1F; }

.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
.fade-up.visible { opacity: 1; transform: translateY(0); }

@media (max-width: 767px) {
    .site-footer-bottom {
        align-items: flex-start;
        flex-direction: column;
    }
}