/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 1200px;
}

/* 16:9 海报区域 */
.banner-wrapper {
    width: 100%;
    aspect-ratio: 16 / 9;
    position: relative;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4);
    margin-bottom: 40px;
}

.banner-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.banner-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(to bottom, transparent 60%, rgba(0,0,0,0.6) 100%);
    pointer-events: none;
}

/* 功能按钮区域 */
.buttons-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    max-width: 900px;
    margin: 0 auto;
}

.function-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 30px 20px;
    background: rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    color: #fff;
}

.function-btn:hover {
    transform: translateY(-8px);
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.3);
}

/* 按钮图标 - 白色圆形底色 */
.btn-icon {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
    font-size: 28px;
    /* 增强对比度的阴影 */
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.35), inset 0 0 0 1px rgba(0, 0, 0, 0.06);
}

.btn-icon img {
    width: 36px;
    height: 36px;
    object-fit: contain;
}

.btn-name {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: 1px;
}

/* 响应式 */
@media (max-width: 768px) {
    .buttons-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }

    .btn-icon {
        width: 56px;
        height: 56px;
        font-size: 24px;
    }
    
    .btn-icon img {
        width: 32px;
        height: 32px;
    }

    .btn-name {
        font-size: 16px;
    }
}

@media (max-width: 480px) {
    .buttons-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }

    .function-btn {
        padding: 20px 16px;
    }

    .btn-icon {
        width: 48px;
        height: 48px;
        margin-bottom: 12px;
    }
    
    .btn-icon img {
        width: 28px;
        height: 28px;
    }

    .btn-name {
        font-size: 14px;
    }
}