:root {
    --primary-color: #007DFF; /* 华为蓝 */
    --accent-color: #52C41A;  /* 健康绿 */
    --bg-color: #f5f5f7;
    --text-main: #1d1d1f;
    --card-bg: rgba(255, 255, 255, 0.8);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "HarmonyOS Sans SC", "SF Pro SC", "PingFang SC", sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏毛玻璃 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    height: 70px;
    display: flex;
    align-items: center;
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    z-index: 1000;
    border-bottom: 1px solid rgba(0,0,0,0.05);
}

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

.logo {
    font-size: 1.4rem;
    font-weight: 700;
}

.logo span {
    color: var(--primary-color);
    font-weight: 400;
    font-size: 0.9rem;
}

.nav-links {
    list-style: none;
    display: flex;
    align-items: center;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-main);
    font-size: 0.95rem;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    padding-top: 150px;
    padding-bottom: 100px;
    background: radial-gradient(circle at 90% 10%, #e3f2fd 0%, #f5f5f7 50%);
}

.hero .container {
    display: flex;
    align-items: center;
    gap: 50px;
}

.hero-content h1 {
    font-size: 3.5rem;
    line-height: 1.2;
    margin-bottom: 20px;
}

.hero-content p {
    font-size: 1.2rem;
    color: #86868b;
    margin-bottom: 35px;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    padding: 12px 28px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 500;
    transition: transform 0.2s;
    display: inline-block;
}

.btn-secondary {
    margin-left: 15px;
    color: var(--primary-color);
    text-decoration: none;
}

/* Mockup 演示 */
.mockup {
    width: 280px;
    height: 560px;
    background: #000;
    border: 8px solid #333;
    border-radius: 40px;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: 0 25px 50px rgba(0,0,0,0.1);
}

.screen-content {
    width: 92%;
    height: 96%;
    background: #fff;
    border-radius: 32px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.bmi-circle {
    width: 120px;
    height: 120px;
    border: 8px solid var(--accent-color);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--accent-color);
    margin-bottom: 20px;
}

/* Card Section */
.features {
    padding: 100px 0;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 60px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.card {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 24px;
    transition: 0.3s ease;
    border: 1px solid transparent;
}

.card:hover {
    transform: translateY(-10px);
    border: 1px solid var(--primary-color);
    background: #fff;
}

.card .icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

/* 动画类 */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease-out;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

footer {
    text-align: center;
    padding: 50px;
    color: #86868b;
    font-size: 0.9rem;
}

/* 移动端适配 */
@media (max-width: 768px) {
    .hero .container { flex-direction: column; text-align: center; }
    .hero-content h1 { font-size: 2.5rem; }
    .nav-links { display: none; } /* 移动端可隐藏或改为汉堡菜单 */
}