/* CSS变量，用于主题切换 */
:root {
    --bg-color: #f8f9fa;
    --text-color: #212529;
    --panel-bg: rgba(255, 255, 255, 0.85);
    --button-bg: #e9ecef;
    --button-text: #495057;
    --shadow-color: rgba(0, 0, 0, 0.15);
    --icon-color: #495057;
}

body.dark-mode {
    --bg-color: #121212;
    --text-color: #e0e0e0;
    --panel-bg: rgba(30, 30, 30, 0.85);
    --button-bg: #333;
    --button-text: #e0e0e0;
    --shadow-color: rgba(0, 0, 0, 0.4);
    --icon-color: #e0e0e0;
}

/* 全局样式 */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    margin: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
}

/* 内容区域 */
.content-wrapper {
    height: 100vh;
    overflow-y: scroll;
    -webkit-overflow-scrolling: touch;
}

#content-display {
    padding: 30px;
    margin: 0 auto;
    max-width: 800px;
}

/* 我们现在为每个段落p标签设置样式 */
#content-display p {
    font-family: 'Georgia', 'serif';
    font-size: 18px; /* 默认字体大小, 会被JS修改 */
    line-height: 1.8;
    margin: 0 0 1.2em 0; /* 段落下边距 */
    transition: font-size 0.2s ease-out; /* 字体平滑过渡 */
    white-space: pre-line; /* 保留换行符，合并多个空格 */
}

/* 浮动控件容器 (保持不变) */
.floating-controls-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 100;
    display: flex;
    align-items: center;
}

.menu-toggle-btn {
    width: 48px;
    height: 48px;
    background-color: var(--panel-bg);
    border: none;
    border-radius: 50%;
    box-shadow: 0 4px 12px var(--shadow-color);
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: transform 0.3s ease, opacity 0.3s ease;
    opacity: 0;
    transform: translateY(-20px);
    pointer-events: none;
}
.menu-toggle-btn.visible {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}
.menu-toggle-btn svg {
    fill: var(--icon-color);
    transition: fill 0.3s;
}

/* 菜单面板 (保持不变) */
.menu-panel {
    display: flex;
    gap: 10px;
    background-color: var(--panel-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    padding: 8px;
    border-radius: 24px;
    box-shadow: 0 4px 12px var(--shadow-color);
    margin-right: 15px;
    transform-origin: right center;
    transform: scaleX(0);
    opacity: 0;
    transition: transform 0.3s cubic-bezier(0.165, 0.84, 0.44, 1), opacity 0.2s ease;
    pointer-events: none;
}
.menu-panel.open {
    transform: scaleX(1);
    opacity: 1;
    pointer-events: auto;
}
.menu-panel button {
    background-color: var(--button-bg);
    color: var(--button-text);
    border: none;
    border-radius: 16px;
    padding: 8px 16px;
    font-size: 1em;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
}
.menu-panel button:active {
    transform: scale(0.95);
}