.placeholder-img {
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #E5E7EB;
    color: #FFFFFF;
    font-size: 0.875rem;
    text-align: center;
    border-radius: 0.5rem;
    overflow: hidden;
}

.placeholder-img::after {
    content: attr(data-text);
    padding: 1rem;
    line-height: 1.5;
}

html {
    scroll-behavior: smooth;
}

.nav-link-active {
    color: #1677FF !important;
    font-weight: 600;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in-up {
    animation: fadeInUp 0.6s ease-out forwards;
}

.animate-delay-1 { animation-delay: 0.1s; }
.animate-delay-2 { animation-delay: 0.2s; }
.animate-delay-3 { animation-delay: 0.3s; }
.animate-delay-4 { animation-delay: 0.4s; }

/* 手机样机样式 */
.phone-mockup {
    background: linear-gradient(180deg, rgba(255,255,255,0.08) 0%, rgba(255,255,255,0.03) 100%);
    backdrop-filter: blur(4px);
    position: relative;
}

.phone-mockup::before {
    content: '';
    position: absolute;
    top: 12px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 24px;
    border-radius: 9999px;
    background-color: rgba(0,0,0,0.25);
}

/* 立即扫码按钮 hover 二维码弹窗 */
.qr-btn-wrapper {
    position: relative;
}

.qr-popup {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    width: 200px;
    padding: 16px;
    background: white;
    border-radius: 14px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.15);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all 0.2s ease;
    z-index: 50;
}

.qr-btn-wrapper:hover .qr-popup,
.qr-popup:hover {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.qr-popup::before {
    content: '';
    position: absolute;
    top: -6px;
    right: 20px;
    width: 12px;
    height: 12px;
    background: white;
    transform: rotate(45deg);
}