/* ==================== 全局变量 ==================== */
:root {
    /* 颜色系统 */
    --bg-white: #FFFFFF;
    --bg-light: #FAFAFA;
    --bg-subtle: #F5F5F5;
    --text-black: #111827;
    --text-dark: #1F2937;
    --text-gray: #4B5563;
    --text-light: #6B7280;
    --text-muted: #9CA3AF;
    --primary-blue: #2563EB;
    --success-green: #10B981;
    --warning-orange: #F59E0B;
    --error-red: #EF4444;
    --border-light: #E5E7EB;
    --phone-bg: #1C1C1E;
    
    /* 手机尺寸变量 */
    --phone-width: 280px;
    --phone-ratio: 2.167;
    --status-bar: 44px;
    --home-indicator: 34px;
    --side-padding: 0px;
    --phone-radius: 36px;
    --screen-radius: 28px;
}

/* ==================== 基础重置 ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    overflow: hidden;
    height: 100%;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-white);
    color: var(--text-dark);
    overflow: hidden;
    height: 100%;
    line-height: 1.6;
}

/* ==================== 页面布局 ==================== */
.page {
    height: 100vh;
    min-height: 100vh;
    max-height: 100vh;
    scroll-snap-align: start;
    scroll-snap-stop: always;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.content {
    max-width: 1200px;
    width: 100%;
    height: 100%;
    padding: 60px 48px;
    display: flex;
    align-items: center;
}

/* 左右分栏布局 */
.page-layout {
    display: flex;
    width: 100%;
    height: 100%;
    align-items: center;
    gap: 60px;
}

.text-column {
    flex: 0 0 36%;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.visual-column {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ==================== 页面导航 ==================== */
.page-nav {
    position: fixed;
    right: 24px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    flex-direction: column;
    gap: 10px;
    z-index: 100;
}

.nav-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--border-light);
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    padding: 0;
}

.nav-dot:hover {
    background: var(--text-muted);
    transform: scale(1.2);
}

.nav-dot.active {
    background: var(--primary-blue);
    transform: scale(1.3);
}

/* ==================== 通用动画 ==================== */
@keyframes fadeInUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes bounce {
    0%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    50% {
        transform: translateX(-50%) translateY(8px);
    }
}

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
    .content {
        padding: 48px 32px;
    }
    
    .page-layout {
        flex-direction: column;
        gap: 40px;
    }
    
    .text-column {
        flex: none;
        width: 100%;
        text-align: center;
    }
    
    :root {
        --phone-width: 240px;
    }
}

@media (max-width: 640px) {
    .content {
        padding: 32px 20px;
    }
    
    :root {
        --phone-width: 200px;
        --phone-radius: 28px;
        --screen-radius: 22px;
    }
}