/* =========================================
           0. 全局设置 (保留)
           ========================================= */
:root {
    --bg-core: #050505;
    --text-main: #ffffff;
    --text-muted: #94a3b8;
    --primary: #2997ff;
    --primary-glow: rgba(41, 151, 255, 0.4);
    --border: rgba(255, 255, 255, 0.1);
    --card-bg: rgba(255, 255, 255, 0.03);
    --card-border: rgba(255, 255, 255, 0.08);
    --card-hover-border: rgba(41, 151, 255, 0.3);
}

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

/* 隐藏滚动条但允许滚动 */
::-webkit-scrollbar {
    display: none;
}

html {
    scrollbar-width: none;
    -ms-overflow-style: none;
    scroll-behavior: smooth;
    height: 100%;
}

body {
    background-color: var(--bg-core);
    color: var(--text-main);
    font-family: "SF Pro Display", "SF Pro Text", "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
    width: 100vw;
    height: 100%;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

/* =========================================
           1. 背景动画 (保留)
           ========================================= */
.background-container {
    position: fixed;
    inset: 0;
    z-index: -1;
    overflow: hidden;
    perspective: 1000px;
    background: radial-gradient(circle at 50% 0%, #111827 0%, #000000 80%);
    pointer-events: none;
}

.tech-grid {
    position: absolute;
    width: 200%;
    height: 200%;
    top: -50%;
    left: -50%;
    background-image:
        linear-gradient(rgba(41, 151, 255, 0.07) 1px, transparent 1px),
        linear-gradient(90deg, rgba(41, 151, 255, 0.07) 1px, transparent 1px);
    background-size: 60px 60px;
    transform: rotateX(60deg) translateY(0);
    animation: gridMove 20s linear infinite;
    mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 1) 40%, rgba(0, 0, 0, 0) 90%);
}

@keyframes gridMove {
    0% {
        transform: rotateX(60deg) translateY(0);
    }

    100% {
        transform: rotateX(60deg) translateY(60px);
    }
}

.floating-symbol {
    position: absolute;
    color: var(--primary);
    opacity: 0;
    font-family: "Menlo", monospace;
    font-weight: bold;
    user-select: none;
    animation: floatUp 10s infinite linear;
    text-shadow: 0 0 10px var(--primary-glow);
}

@keyframes floatUp {
    0% {
        transform: translateY(100vh) scale(0.5);
        opacity: 0;
    }

    20% {
        opacity: 0.4;
    }

    80% {
        opacity: 0.4;
    }

    100% {
        transform: translateY(-10vh) scale(1.2);
        opacity: 0;
    }
}

/* =========================================
           2. 导航栏 (保留)
           ========================================= */
nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 64px;
    z-index: 100;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 32px;
    background: rgba(5, 5, 5, 0.6);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
}

.logo {
    font-weight: 700;
    font-size: 1.2rem;
    letter-spacing: -0.5px;
    color: #fff;
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-center-title {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.05);
    padding: 4px 12px;
    border-radius: 99px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    display: flex;
    align-items: center;
    gap: 6px;
}

.nav-center-title::before {
    content: '';
    width: 6px;
    height: 6px;
    background: var(--success, #30d158);
    border-radius: 50%;
    display: block;
    box-shadow: 0 0 8px var(--success, #30d158);
}

.nav-right {
    display: flex;
    gap: 20px;
    align-items: center;
}

.nav-link {
    color: #888;
    font-size: 0.9rem;
    transition: color 0.3s;
    cursor: pointer;
}

.nav-link:hover {
    color: #fff;
}

.mobile-menu-btn {
    display: none;
    cursor: pointer;
}

/* 移动端菜单样式 */
.mobile-menu-overlay {
    position: fixed;
    inset: 0;
    background: rgba(5, 5, 5, 0.98);
    z-index: 99;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 30px;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
    backdrop-filter: blur(10px);
}

.mobile-menu-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.mobile-nav-link {
    font-size: 1.5rem;
    color: #fff;
    font-weight: 600;
}

@media (max-width: 768px) {
    .nav-right {
        display: none;
    }

    .mobile-menu-btn {
        display: block;
    }

    .nav-center-title {
        display: none;
    }
}

/* =========================================
           3. 通用组件 (保留基础按钮)
           ========================================= */
.btn {
    padding: 0 24px;
    height: 44px;
    border-radius: 99px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    white-space: nowrap;
}

.btn-primary {
    background: #fff;
    color: #000;
    border: 1px solid #fff;
}

.btn-primary:hover {
    background: #e2e2e2;
    transform: translateY(-2px);
}

.btn-outline {
    background: rgba(255, 255, 255, 0.05);
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(5px);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: #fff;
    transform: translateY(-2px);
}

/* =========================================
           4. 页面容器 (新内容写在这里)
           ========================================= */
.main-container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 100px 20px 40px 20px;
    /* 顶部留出导航栏高度 */
    min-height: 100vh;
}

/* 示例内容样式 */
.placeholder-content {
    text-align: center;
    margin-top: 100px;
}

.page-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 20px;
    background: linear-gradient(110deg, #fff 0%, #888 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* =========================================
   Pricing grid / cards (追加样式)
   ========================================= */
.pricing-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
        gap: 30px;
        margin-top: 50px;
    }
    .pricing-card {
        background: var(--card-bg);
        border: 1px solid var(--card-border);
        border-radius: 20px;
        padding: 40px 30px;
        position: relative;
        transition: all 0.3s ease;
        display: flex;
        flex-direction: column;
    }
    .pricing-card:hover {
        border-color: var(--card-hover-border);
        transform: translateY(-5px);
        box-shadow: 0 10px 30px -10px rgba(0,0,0,0.5);
    }
    .pricing-card.featured {
        background: rgba(41, 151, 255, 0.08); /* 轻微的蓝色背景 */
        border-color: rgba(41, 151, 255, 0.3);
    }
    .pricing-header h3 { font-size: 1.5rem; margin-bottom: 10px; color: #fff; }
    .pricing-price { font-size: 2.5rem; font-weight: 700; margin-bottom: 20px; color: #fff; }
    .pricing-price span { font-size: 1rem; color: var(--text-muted); font-weight: 400; }
    .pricing-features { list-style: none; margin-bottom: 30px; flex-grow: 1; }
    .pricing-features li { margin-bottom: 12px; color: var(--text-muted); display: flex; align-items: center; gap: 10px; }
    .pricing-features li svg { color: var(--success, #30d158); flex-shrink: 0; }

    .donation-container {
        max-width: 500px;
        margin: 60px auto;
        background: rgba(20, 20, 20, 0.6);
        border: 1px solid var(--border);
        border-radius: 24px;
        padding: 40px;
        backdrop-filter: blur(20px);
        text-align: center;
    }
    .input-group {
        position: relative;
        margin: 30px 0;
    }
    .currency-symbol {
        position: absolute;
        left: 20px;
        top: 50%;
        transform: translateY(-50%);
        font-size: 1.5rem;
        color: #fff;
    }
    .amount-input {
        width: 100%;
        background: transparent;
        border: 2px solid var(--border);
        border-radius: 12px;
        padding: 15px 15px 15px 50px;
        font-size: 2rem;
        color: #fff;
        font-weight: bold;
        outline: none;
        transition: border-color 0.3s;
    }
    .amount-input:focus {
        border-color: var(--primary);
    }
    .quick-amounts {
        display: flex;
        gap: 10px;
        justify-content: center;
        margin-bottom: 30px;
    }
    .amount-chip {
        background: rgba(255,255,255,0.1);
        border: 1px solid transparent;
        border-radius: 8px;
        padding: 8px 16px;
        color: #fff;
        cursor: pointer;
        transition: all 0.2s;
    }
    .amount-chip:hover { background: rgba(255,255,255,0.2); }
    .amount-chip.active { background: var(--primary); }

    .checkout-layout {
        display: flex;
        flex-wrap: wrap;
        gap: 40px;
        margin-top: 60px;
        align-items: flex-start;
    }
    .order-details {
        flex: 2;
        min-width: 300px;
    }
    .order-summary {
        flex: 1;
        min-width: 280px;
        background: var(--card-bg);
        border: 1px solid var(--card-border);
        border-radius: 16px;
        padding: 30px;
    }
    .item-row {
        display: flex;
        gap: 20px;
        padding: 20px 0;
        border-bottom: 1px solid var(--border);
    }
    .item-img {
        width: 80px;
        height: 80px;
        background: linear-gradient(135deg, #333, #111);
        border-radius: 12px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 2rem;
    }
    .summary-row {
        display: flex;
        justify-content: space-between;
        margin-bottom: 15px;
        color: var(--text-muted);
    }
    .summary-total {
        display: flex;
        justify-content: space-between;
        margin-top: 20px;
        padding-top: 20px;
        border-top: 1px solid var(--border);
        font-size: 1.2rem;
        font-weight: bold;
        color: #fff;
    }