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

:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --bg-color: #f9fafb;
    --card-bg: #ffffff;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部 */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 60px 0;
    margin-bottom: 40px;
    border-radius: 0 0 20px 20px;
    box-shadow: var(--shadow-md);
}

.header-content h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* 搜索栏 */
.search-container {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
    justify-content: center;
}

.search-box {
    flex: 1;
    max-width: 500px;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.search-box:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.search-btn {
    padding: 12px 24px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
}

.search-btn:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* 分类导航 */
.categories {
    display: flex;
    gap: 10px;
    margin-bottom: 40px;
    flex-wrap: wrap;
    justify-content: center;
}

.category-btn {
    padding: 10px 20px;
    border: 2px solid var(--border-color);
    background-color: white;
    border-radius: 25px;
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 600;
    transition: all 0.3s ease;
    color: var(--text-secondary);
}

.category-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
}

.category-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

/* 工具网格 */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
    margin-bottom: 60px;
}

.tool-card {
    background-color: var(--card-bg);
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    cursor: pointer;
    border: 2px solid transparent;
    display: flex;
    flex-direction: column;
    position: relative;
}

.tool-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.tool-card.is-favorite {
    border-color: rgba(245, 158, 11, 0.45);
    background: linear-gradient(180deg, #fffbeb 0%, #ffffff 42%);
}

.favorite-btn {
    position: absolute;
    top: 12px;
    right: 12px;
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 999px;
    background-color: rgba(249, 250, 251, 0.95);
    color: #d1d5db;
    font-size: 1.2rem;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    z-index: 2;
    box-shadow: var(--shadow);
}

.favorite-btn:hover {
    color: var(--warning-color);
    transform: scale(1.08);
}

.favorite-btn.active {
    color: var(--warning-color);
    background-color: #fff7ed;
}

.tool-icon {
    font-size: 2.5rem;
    margin-bottom: 12px;
    padding-right: 36px;
}

.tool-name {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.tool-description {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 16px;
    flex: 1;
}

.tool-category {
    display: inline-block;
    background-color: var(--bg-color);
    color: var(--primary-color);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
}

.tool-card.converter .tool-category {
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
}

.tool-card.generator .tool-category {
    background-color: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

.tool-card.calculator .tool-category {
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--danger-color);
}

.tool-card.utility .tool-category {
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--primary-color);
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* 打赏菜单按钮 */
.donation-menu-btn {
    background: linear-gradient(135deg, #f472b6, #ec4899);
    color: white;
    border-color: transparent;
}

.donation-menu-btn:hover,
.donation-menu-btn.active {
    background: linear-gradient(135deg, #ec4899, #db2777);
    color: white;
    border-color: transparent;
    transform: translateY(-2px);
}

/* 打赏弹层 */
.donation-overlay {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    background-color: rgba(17, 24, 39, 0.45);
    backdrop-filter: blur(2px);
}

.donation-overlay.hidden {
    display: none;
}

.donation-card {
    background-color: var(--card-bg);
    border-radius: 12px;
    padding: 20px;
    box-shadow: var(--shadow-md);
    border-left: 4px solid var(--secondary-color);
    max-width: 280px;
    width: 100%;
    animation: slideInRight 0.35s ease;
    position: relative;
    transition: all 0.3s ease;
}

.donation-close-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: all 0.3s ease;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
}

.donation-close-btn:hover {
    color: var(--text-primary);
    transform: scale(1.2);
}

.donation-card h3 {
    font-size: 1.1rem;
    margin-bottom: 8px;
    color: var(--text-primary);
    padding-right: 20px;
}

.donation-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 12px;
}

.qr-code-container {
    display: flex;
    justify-content: center;
    margin-bottom: 12px;
}

.qr-code-placeholder {
    width: 160px;
    height: 160px;
    background-color: var(--bg-color);
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--text-secondary);
}

.qr-code-placeholder p {
    margin: 4px 0;
}

.qr-text {
    font-size: 0.8rem !important;
    font-style: italic;
}

.qr-code-image {
    width: 180px;
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    display: block;
    box-shadow: var(--shadow-sm);
}

.donation-tips {
    font-size: 0.8rem !important;
    text-align: center;
    color: var(--text-secondary);
}

/* 页脚 */
.footer {
    background-color: var(--text-primary);
    color: white;
    text-align: center;
    padding: 30px 20px;
    margin-top: 60px;
    border-radius: 12px 12px 0 0;
}

/* 动画 */
@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* 工具页面返回链接 */
.back-link {
    display: inline-block;
    margin-bottom: 30px;
    padding: 8px 16px;
    background-color: var(--bg-color);
    color: var(--primary-color);
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s ease;
}

.back-link:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateX(-5px);
}

/* 工具页面内容样式 */
.tool-content {
    background-color: var(--card-bg);
    border-radius: 12px;
    padding: 40px;
    box-shadow: var(--shadow-md);
    margin-bottom: 60px;
}

.tool-content h1 {
    font-size: 2rem;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.tool-content h2 {
    font-size: 1.3rem;
    margin-top: 30px;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.tool-content p {
    margin-bottom: 15px;
    line-height: 1.8;
}

.tool-content input,
.tool-content textarea,
.tool-content select {
    width: 100%;
    padding: 12px;
    margin-bottom: 15px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
}

.tool-content input:focus,
.tool-content textarea:focus,
.tool-content select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.tool-content input[type="checkbox"] {
    width: auto;
    padding: 0;
    margin: 0;
    border: none;
    box-shadow: none;
}

.tool-content button {
    padding: 12px 24px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
}

.tool-content button:hover {
    background-color: var(--secondary-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.result-box {
    background-color: var(--bg-color);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    margin-top: 20px;
    word-break: break-all;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header-content h1 {
        font-size: 2rem;
    }

    .search-container {
        flex-direction: column;
    }

    .search-box {
        max-width: 100%;
    }

    .tools-grid {
        grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
        gap: 16px;
    }

    .donation-menu-btn {
        width: auto;
    }

    .donation-card {
        max-width: 100%;
    }

    .tool-content {
        padding: 20px;
    }

    .tool-content h1 {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .header-content h1 {
        font-size: 1.5rem;
    }

    .subtitle {
        font-size: 1rem;
    }

    .categories {
        gap: 8px;
    }

    .category-btn {
        padding: 8px 16px;
        font-size: 0.85rem;
    }

    .tools-grid {
        grid-template-columns: 1fr;
    }

    .tool-card {
        padding: 16px;
    }

    .tool-icon {
        font-size: 2rem;
    }
}