/* 优化的CSS变量和根样式 - 高性能版本 */
:root {
    /* 主题核心颜色 - 减少变量数量提高性能 */
    --theme-color: #f1404b;
    --theme-color-rgb: 241, 64, 75;
    --theme-card-bg: #fff;
    --theme-card-header-bg: #f8f9fa;
    --main-bg-color: #fff;
    --main-color: #495057;
    --theme-text-color: #495057;
    --theme-heading-color: #212529;
    --theme-border-color: #e9ecef;
    --muted-bg-a-color: #f8f9fa;
    --theme-border-radius: 8px;
    --theme-border-radius-sm: 4px;
    --dark-message-bg: #2a2c2e;
    --symbol-border-color: #e9ecef;
    --copy-message-z-index: 1050;
    --main-radius: var(--theme-border-radius);
    /* 新增字体设置以确保符号正确显示 */
    --symbol-font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

/* 夜间模式变量定义 - 最小化切换时的计算量 */
.io-black-mode {
    --main-bg-color: #363738;
    --main-color: #bbb;
    --theme-card-bg: #363738;
    --theme-card-header-bg: #2c2e2f;
    --theme-border-color: rgba(68, 68, 68, .1);
    --symbol-border-color: rgba(68, 68, 68, .1);
    --theme-heading-color: #ddd;
    --theme-text-color: #bbb;
    --muted-bg-a-color: #2c2e2f;
}

/* 禁用不必要的CSS过渡，提高主题切换性能 */
*,
*::before,
*::after {
    /* 仅在必要时使用过渡效果 */
    transition-property: none !important;
    transition-delay: 0s !important;
    transition-duration: 0s !important;
}

/* 仅为交互元素启用最小化过渡 */
.symbol-grid-item,
.symbol-list span,
.tool-navi a {
    transition-property: background-color, transform !important;
    transition-duration: 0.15s !important;
    transition-timing-function: ease !important;
}

/* 基础组件样式 */
.tool-form {
    background: var(--main-bg-color);
    border-radius: var(--theme-border-radius);
    padding: 20px;
}

.tool-navi {
    margin-bottom: 20px;
    background: var(--main-bg-color);
    padding: 10px 0;
    z-index: 100;
    border-radius: var(--theme-border-radius);
    transform: translateZ(0);
    /* 硬件加速 */
    position: static !important;
    overflow: visible !important;
    width: 100% !important;
    box-sizing: border-box !important;
}

/* 移除所有可能的固定定位样式 */
.tool-navi.fixed {
    position: static !important;
    box-shadow: none !important;
    padding: 10px 0 !important;
    width: 100% !important;
    margin-left: 0 !important;
    margin-right: 0 !important;
    max-width: none !important;
    z-index: 100 !important;
    overflow: visible !important;
    left: 0 !important;
    right: 0 !important;
}

.tool-navi ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-wrap: nowrap;
    gap: 10px;
    padding-bottom: 10px;
    overflow: visible;
    width: 100%;
    box-sizing: border-box;
    max-width: none;
    white-space: nowrap;
}

.tool-navi li {
    margin: 0;
}

.tool-navi a {
    display: block;
    padding: 8px 16px;
    text-decoration: none;
    color: var(--theme-text-color);
    border-radius: var(--theme-border-radius-sm);
    font-weight: 500;
    background: var(--muted-bg-a-color);
}

.tool-navi a:hover {
    background: var(--theme-color);
    color: white;
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(var(--theme-color-rgb), 0.3);
}

.panel {
    margin-bottom: 25px;
    border: 1px solid var(--theme-border-color);
    border-radius: var(--theme-border-radius);
    overflow: hidden;
    background: var(--theme-card-bg);
    transform: translateZ(0);
}

.panel-heading {
    background: var(--theme-card-header-bg);
    padding: 15px 20px;
    border-bottom: 1px solid var(--theme-border-color);
}

.panel-heading h5 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--theme-heading-color);
}

.panel-body {
    padding: 20px;
    background: var(--theme-card-bg);
}

/* 高性能符号网格布局 - 优化以确保所有符号都能完整显示 */
.symbol-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(55px, 1fr));
    gap: 10px;
    padding: 0;
    margin: 0;
    transform: translateZ(0);
    justify-items: center;
}

.symbol-grid-item {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 12px 15px;
    border: 1px solid var(--symbol-border-color);
    border-radius: var(--theme-border-radius-sm);
    cursor: pointer;
    background: var(--main-bg-color);
    color: var(--main-color);
    font-size: 1.4rem;
    /* 增大字体以确保符号清晰可见 */
    min-height: 60px;
    min-width: 60px;
    text-align: center;
    user-select: none;
    transform: translateZ(0);
    box-sizing: border-box;
    overflow: visible;
    white-space: nowrap;
    font-family: var(--symbol-font-family);
    /* 增加行高以确保垂直居中 */
    line-height: 1.2;
    /* 确保符号不会被截断 */
    flex-shrink: 0;
    word-break: keep-all;
}

.symbol-grid-item:hover {
    background: var(--theme-color);
    color: white;
    border-color: var(--theme-color);
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(var(--theme-color-rgb), 0.3);
}

/* 符号列表样式 - 优化以确保符号完整显示 */
.symbol-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    transform: translateZ(0);
}

.symbol-list li {
    margin: 0;
}

.symbol-list span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 15px;
    border: 1px solid var(--symbol-border-color);
    border-radius: var(--theme-border-radius-sm);
    cursor: pointer;
    background: var(--main-bg-color);
    color: var(--main-color);
    font-size: 1.4rem;
    min-width: 60px;
    min-height: 60px;
    text-align: center;
    user-select: none;
    transform: translateZ(0);
    box-sizing: border-box;
    overflow: visible;
    white-space: nowrap;
    font-family: var(--symbol-font-family);
    line-height: 1.2;
    flex-shrink: 0;
    word-break: keep-all;
}

.symbol-list span:hover {
    background: var(--theme-color);
    color: white;
    border-color: var(--theme-color);
    box-shadow: 0 2px 8px rgba(var(--theme-color-rgb), 0.3);
}

/* 提示和信息样式 */
.tips {
    margin-top: 15px;
    padding: 5px 0;
    background: none;
    background-color: transparent;
    border-left: none;
    border-radius: var(--theme-border-radius-sm);
    font-size: 0.8rem;
}

.symbol-info {
    margin-bottom: 20px;
    transform: translateZ(0);
}

.symbol-info .tips {
    margin: 0;
    padding: 5px 0;
    background: none;
    background-color: transparent;
    border-left: none;
    font-size: 0.8rem;
}

/* 复制成功消息 - 简化动画 */
.copy-message {
    position: fixed;
    top: 20%;
    left: 50%;
    transform: translateX(-50%);
    background: white;
    padding: 12px 20px;
    border-radius: var(--theme-border-radius-sm);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    z-index: var(--copy-message-z-index);
    opacity: 0;
    transition: opacity 0.2s ease;
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 500;
    border: 1px solid #e9ecef;
    max-width: 200px;
    width: auto;
    white-space: nowrap;
}

.copy-message.show {
    opacity: 1;
}

.copy-message::before {
    content: '✓';
    display: inline-block;
    width: 20px;
    height: 20px;
    background: #4CAF50;
    color: white;
    border-radius: 50%;
    text-align: center;
    line-height: 20px;
    font-size: 12px;
    font-weight: bold;
    flex-shrink: 0;
}

.copy-message::after {
    content: none;
}

/* 夜间模式下的复制消息样式 */
.copy-message.dark-theme {
    background: var(--dark-message-bg);
    border-color: rgba(68, 68, 68, .3);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    color: #ddd;
}

/* 导航链接激活状态 */
.nav-link.active {
    background: var(--theme-color);
    color: white;
}

/* 面板标题 */
.panel-header {
    margin-bottom: 8px;
    transform: translateZ(0);
}

.panel-header h1 {
    text-align: center;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--theme-heading-color);
}

/* 夜间模式样式 - 最小化使用 */
.io-black-mode .tool-navi.fixed {
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.3);
}

.io-black-mode .copy-message {
    background: var(--dark-message-bg);
    border-color: rgba(68, 68, 68, .3);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.io-black-mode .tips,
.io-black-mode .symbol-info .tips {
    color: #c5cae9;
}

/* 响应式设计 - 优化性能和符号显示 */
@media (max-width: 768px) {
    .tool-navi {
        position: static !important;
        /* 确保不会在移动设备上固定定位 */
        top: auto !important;
        padding: 8px 0 !important;
        margin-bottom: 10px !important;
        transform: translateZ(0);
        overflow: visible !important;
        width: 100% !important;
        box-sizing: border-box !important;
        margin-left: 0 !important;
        margin-right: 0 !important;
        left: 0 !important;
        right: 0 !important;
    }

    .tool-navi.fixed {
        box-shadow: none !important;
        padding: 8px 0 !important;
        width: 100% !important;
        position: static !important;
        overflow: visible !important;
        margin-left: 0 !important;
        margin-right: 0 !important;
        left: 0 !important;
        right: 0 !important;
        z-index: 100 !important;
    }

    .tool-navi ul {
        gap: 5px !important;
        flex-wrap: nowrap !important;
        overflow-x: auto !important;
        overflow-y: hidden !important;
        padding-bottom: 5px !important;
        justify-content: flex-start !important;
        scrollbar-width: thin !important;
        transform: translateZ(0) !important;
        width: 100% !important;
        box-sizing: border-box !important;
        display: flex !important;
        max-width: none !important;
        white-space: nowrap !important;
        margin: 0 !important;
        padding: 0 !important;
        padding-bottom: 5px !important;
        -webkit-overflow-scrolling: touch !important;
        scroll-behavior: smooth !important;
    }

    .tool-navi ul::-webkit-scrollbar {
        height: 3px;
    }

    .tool-navi ul::-webkit-scrollbar-thumb {
        background: var(--theme-color);
        border-radius: 3px;
    }

    .tool-navi li {
        display: inline-block !important;
        flex-shrink: 0 !important;
        vertical-align: top !important;
        margin: 0 !important;
    }

    .tool-navi a {
        padding: 6px 12px !important;
        font-size: 0.85rem !important;
        white-space: nowrap !important;
        flex-shrink: 0 !important;
        display: block !important;
    }

    .panel-body {
        padding: 15px;
    }

    .symbol-grid {
        gap: 8px;
        grid-template-columns: repeat(auto-fill, minmax(55px, 1fr));
        justify-items: center;
    }

    .symbol-grid-item {
        padding: 12px 10px;
        font-size: 1.3rem;
        min-height: 55px;
        min-width: 55px;
        line-height: 1.2;
        flex-shrink: 0;
        word-break: keep-all;
    }

    .symbol-list {
        gap: 8px;
    }

    .symbol-list span {
        padding: 12px 10px;
        font-size: 1.3rem;
        min-width: 55px;
        min-height: 55px;
        display: flex;
        align-items: center;
        justify-content: center;
        line-height: 1.2;
        flex-shrink: 0;
        word-break: keep-all;
    }

    .copy-message {
        top: 15%;
        padding: 10px 16px;
        font-size: 0.9rem;
        max-width: 90%;
        width: auto;
    }

    .copy-message::before {
        width: 18px;
        height: 18px;
        line-height: 18px;
        font-size: 11px;
    }
}

@media (max-width: 480px) {
    .tool-form {
        padding: 15px;
        margin: 0 -10px;
    }

    .panel {
        margin-bottom: 20px;
        border-radius: 0;
        border-left: none;
        border-right: none;
    }

    .panel-heading {
        padding: 12px 15px;
    }

    .panel-heading h5 {
        font-size: 1rem;
    }

    .symbol-grid {
        grid-template-columns: repeat(auto-fill, minmax(50px, 1fr));
    }

    .symbol-list span {
        padding: 10px 8px;
        font-size: 1.2rem;
        min-width: 50px;
        min-height: 50px;
        line-height: 1.2;
        flex-shrink: 0;
        word-break: keep-all;
    }

    .copy-message {
        padding: 8px 14px;
        font-size: 0.85rem;
    }

    .tool-navi ul {
        justify-content: center;
    }
}

.symbol-info p{
    font-size: 0.8rem; 
    text-align: center;
}