/* === 1. 核心变量与重置 === */
:root {
    --bg-color: #ffffff;
    --text-main: #1a1a1a;
    --text-light: #666666;
    --primary-color: #ffb700; 
    --accent-color: #ffe169;  
    --dark-bg: #0a0e17;
    --dark-card: #141a26;
    --radius-unified: 12px;
    --container-width: 1320px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
    font-family: 'Alibaba PuHuiTi 3.0', 'Alibaba PuHuiTi', 'Inter', 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-main);
    background-color: var(--bg-color);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}
a { text-decoration: none; color: inherit; transition: opacity 0.3s; }
img { width: 100%; height: 100%; display: block; object-fit: cover; }
.container { max-width: var(--container-width); margin: 0 auto; padding: 0 24px; }

/* === 3. 主内容区 (Construction) === */
.construction-section {
    flex: 1; /* 撑满剩余高度 */
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    background-color: #f9fafb; position: relative; overflow: hidden;
    text-align: center; padding: 40px 20px;
}

/* 装饰背景圆 */
.bg-circle {
    position: absolute; border-radius: 50%; opacity: 0.05;
    background: var(--primary-color); z-index: 0;
}
.c1 { width: 600px; height: 600px; top: -100px; right: -100px; }
.c2 { width: 400px; height: 400px; bottom: -50px; left: -50px; }

.content-box { position: relative; z-index: 1; max-width: 600px; }

.status-code {
    margin-bottom: 18px; color: var(--primary-color);
    font-size: clamp(72px, 12vw, 128px); font-weight: 900;
    line-height: 0.9; letter-spacing: -0.08em;
}

.icon-box {
    font-size: 80px; margin-bottom: 30px; color: #ddd;
    animation: float 3s ease-in-out infinite;
}
@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-15px); }
    100% { transform: translateY(0px); }
}

h1 { font-size: 36px; margin-bottom: 16px; color: var(--text-main); }
p { font-size: 16px; color: var(--text-light); margin-bottom: 40px; }

.progress-bar {
    width: 200px; height: 6px; background: #eee; border-radius: 10px; margin: 0 auto 40px;
    overflow: hidden; position: relative;
}
.progress-fill {
    height: 100%; background: var(--primary-color); width: 60%;
    border-radius: 10px; position: absolute; top: 0; left: 0;
    animation: loading 2s infinite ease-in-out;
}
@keyframes loading {
    0% { left: -100%; }
    100% { left: 100%; }
}

.btn-back:hover { background: var(--text-main); color: white; }

.content-box .btn + .btn { margin-left: 10px; }

@media (max-width: 520px) {
    .content-box .btn { display: flex; width: 100%; }
    .content-box .btn + .btn { margin: 12px 0 0; }
}

@media (prefers-reduced-motion: reduce) {
    .icon-box,
    .progress-fill { animation: none; }
}