/* ========== 全局样式 ========== */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color var(--transition-duration) var(--transition-timing),
        color var(--transition-duration) var(--transition-timing);
    line-height: 1.6;
}

/* ========== 主内容区 ========== */

.main-content {
    min-height: calc(100vh - 70px - 200px);
    max-width: 1400px;
    margin: 0 auto;
}

.page {
    display: none;
    opacity: 0;
    animation: fadeIn 0.6s var(--transition-timing) forwards;
}

.page.active {
    display: block;
    opacity: 1;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ========== 占位图 ========== */

.placeholder-image {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--accent-color) 0%, #7c3aed 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    position: relative;
    overflow: hidden;
}

.placeholder-image::before {
    content: '🖼️';
    font-size: 3rem;
    opacity: 0.7;
}