/* 宏观架构 */
.container {
    width: 100%;
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-3);
}

/* 留白比阴影重要，大间距 section */
.section {
    padding: var(--spacing-6) 0;
    position: relative;
    overflow: hidden;
}

@media (max-width: 768px) {
    .section {
        padding: var(--spacing-4) 0;
    }
}

/* 导航栏 */
.app-header {
    height: var(--header-height);
    display: flex;
    align-items: center;
    position: sticky;
    top: 0;
    background-color: rgba(253, 251, 247, 0.85); /* 暖白半透明 */
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    z-index: 100;
    border-bottom: 1px solid transparent;
    transition: var(--transition-slow);
}

.app-header.scrolled {
    border-bottom: 1px solid var(--color-border);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.nav-links {
    display: flex;
    gap: var(--spacing-3);
    align-items: center;
}

.nav-item {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-text-dim);
    transition: var(--transition-fast);
}

.nav-item:hover {
    color: var(--color-text-main);
}

@media (max-width: 768px) {
    .nav-links {
        display: none; /* 移动端极其克制，暂隐导航，只留品牌 */
    }
}

/* Footer Layout */
.app-footer {
    padding: var(--spacing-4) 0;
    border-top: 1px solid var(--color-border);
    margin-top: var(--spacing-2);
}

.footer-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

@media (max-width: 768px) {
    .footer-container {
        flex-direction: column;
        gap: var(--spacing-2);
        text-align: center;
    }
}

/* Grid Layouts to give cards stable rhythm */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-4);
}

.grid-auto {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: var(--spacing-3);
}

@media (max-width: 768px) {
    .grid-2 {
        grid-template-columns: 1fr;
    }

    /* 英雄区：标题缩小，按钮转垂直占满 */
    .hero-title {
        font-size: 3rem;
        word-break: break-word;
    }

    .action-group {
        flex-direction: column;
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
    }

    .action-group .btn {
        width: 100%;
    }
}