/* ==================== CSS 变量定义 ==================== */
:root {
    /* 颜色系统 - 浅色主题 */
    --color-bg-base: #fbfbfa;
    --color-bg-elevated: #ffffff;
    --color-bg-hover: #efefef;
    --color-bg-input: #f8f8f8;
    --color-text-primary: #242424;
    --color-text-secondary: #6b6b6b;
    --color-border-default: #e5e5e5;
    --color-accent-primary: #d97757;
    --color-accent-hover: #c56a4c;
    --color-danger: #d14d4d;
    --color-success: #2d8a56;
    --color-warning: #d9a157;

    /* 阴影系统 */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.08);

    /* 字体系统 */
    --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
    --font-family-mono: "Menlo", "Monaco", "Consolas", monospace;

    /* 固定尺寸布局 - 针对 14 寸 MacBook (1440x900) 优化 */
    --layout-app-width: 1400px;
    --layout-app-height: 860px;
    --layout-header-height: 56px;
    --layout-footer-height: 40px;
    --layout-tab-nav-height: 44px;
    --layout-page-header-height: 60px;
    --layout-content-padding: 20px;

    /* 账号卡片尺寸 */
    --card-width: 280px;
    --card-height: 220px;
    --card-gap: 14px;
    --card-columns: 4;

    /* Chat 尺寸 */
    --chat-sidebar-width: 220px;
    --chat-header-height: 52px;
    --chat-input-min-height: 40px;
}

/* 深色主题 */
[data-theme="dark"] {
    --color-bg-base: #0f0f0f;
    --color-bg-elevated: #1e1e1e;
    --color-bg-hover: #2a2a2a;
    --color-bg-input: #252525;
    --color-text-primary: #f0f0f0;
    --color-text-secondary: #b8b8b8;
    --color-border-default: #2d2d2d;
    --color-accent-primary: #e88b6a;
    --color-accent-hover: #f09d7e;
    --color-danger: #ef5350;
    --color-success: #66bb6a;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.4);
}