.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
    z-index: 10;
    cursor: default;
    /* background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0,0,0,0.05); */
}

/* 英雄区域 */
.hero {
    height: 80vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: radial-gradient(circle at 50% 50%, #f0f4ff 0%, #ffffff 70%);
    text-align: center;
    padding: 4rem 0;
    max-width: 800px;
    margin-bottom: 0.5rem;
    /* margin: 0 auto; */
}

.hero h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    background: linear-gradient(135deg, #4a6cf7 0%, #6a11cb 100%);
    -webkit-background-clip: text;
    background-clip: text;
    /* 为了兼容性，建议加上标准属性 */
    -webkit-text-fill-color: transparent;
    letter-spacing: -1px;
    line-height: 1.3;
    padding-bottom: 0.1em;
    padding-right: 0.1em;
    display: inline-block;
}

.hero p {
    font-size: 1.2rem;
    color: #666;
    max-width: 600px;
    margin: 0 auto;
}


/* --- 占位符样式 (Invisible Placeholders) --- */
/* 这些元素实际上不可见（opacity: 0），但它们占据空间，
       JS 会读取它们的位置和大小，用来指导浮动文字的运动 */

/* 1. 终点：Header 里的文字样式 */
.brand-text-header-placeholder {
    opacity: 0;
    font-size: 2rem;
    font-weight: 600;
    white-space: nowrap;
}

/* 2. 起点：Hero 里的文字样式 */
.brand-text-hero-placeholder {
    opacity: 0;
    font-size: 5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    letter-spacing: -1px;
    line-height: 1.3;
    white-space: nowrap;

}

/* --- 浮动渐变文字 --- */
#floating-text {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 99; 
    pointer-events: none;
    transform-origin: top left;
    will-change: transform;
    font-size: 5rem;
    font-weight: 600; 
    line-height: 1.1; 
    letter-spacing: -0.03em;
    margin: 0;
    padding: 0.1em; 
    white-space: nowrap;
    background: linear-gradient(
        180deg, 
        #ffffff 30%, 
        #a3a3a3 100%
    );
    mix-blend-mode: difference;
    -webkit-background-clip: text;
    background-clip: text;
    color: #fff; 
    -webkit-text-fill-color: transparent;
}