/* ============================================================
   EduHelp — CSS Variables (Swiss Banknote × Japanese Aesthetics)
   ============================================================ */

:root {
  /* === 骨架色（不随主题切换）=== */
  --bg-page: #F7F5F2;
  --bg-card: #FFFFFF;
  --bg-sidebar: #F0EDE8;
  --bg-input: #FFFFFF;
  --bg-hover: #E8E4DE;
  --bg-overlay: rgba(0, 0, 0, 0.04);

  --text-primary: #1A1A1A;
  --text-secondary: #5C5C5C;
  --text-tertiary: #8A8A8A;
  --text-disabled: #BDBDBD;
  --text-inverse: #FFFFFF;

  --border-default: #E0DCD6;
  --border-divider: #E8E4DE;
  --border-focus: #1E6BA8;

  /* === 品牌色（默认 Swiss Blue，随主题切换）=== */
  --brand-primary: #1E6BA8;
  --brand-hover: #0F4C81;
  --brand-light: #D6EAF8;
  --brand-lighter: #EBF4FA;

  /* === 语义色 === */
  --semantic-success: #2E8B57;
  --semantic-warning: #D4A017;
  --semantic-error: #C41E3A;
  --semantic-info: #1E6BA8;

  /* === 代码块（日间）=== */
  --code-bg: #F5F2EE;
  --code-text: #2D2D2D;
  --code-keyword: #6B2D8F;
  --code-string: #2E8B57;
  --code-comment: #8A8A8A;
  --code-function: #C41E3A;
  --code-number: #1E6BA8;

  /* === 布局变量 === */
  --sidebar-width: 260px;
  --header-height: 56px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --transition-fast: 0.15s ease;
  --transition-base: 0.3s ease;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04), 0 1px 3px rgba(0,0,0,0.03);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06), 0 2px 4px rgba(0,0,0,0.04);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.04);
  --shadow-glass: 0 8px 32px rgba(0,0,0,0.06);

  /* === 字体 === */
  --font-sans: "PingFang SC", -apple-system, BlinkMacSystemFont, "Hiragino Sans GB", "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
  --font-mono: "SF Mono", "JetBrains Mono", "Fira Code", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

/* === 夜间模式 === */
[data-theme="dark"] {
  --bg-page: #121212;
  --bg-card: #1E1E1E;
  --bg-sidebar: #181818;
  --bg-input: #252525;
  --bg-hover: #2A2A2A;
  --bg-overlay: rgba(255, 255, 255, 0.04);

  --text-primary: #E8E4DE;
  --text-secondary: #A8A4A0;
  --text-tertiary: #7A7672;
  --text-disabled: #555555;
  --text-inverse: #121212;

  --border-default: #333333;
  --border-divider: #2A2A2A;
  --border-focus: #4A9FD8;

  --brand-primary: #4A9FD8;
  --brand-hover: #6BB3E0;
  --brand-light: #1A3A52;
  --brand-lighter: #142536;

  --semantic-success: #4CAF7A;
  --semantic-warning: #E8C547;
  --semantic-error: #E85D70;
  --semantic-info: #4A9FD8;

  --code-bg: #1A1A1A;
  --code-text: #D4D0CC;
  --code-keyword: #B085D8;
  --code-string: #4CAF7A;
  --code-comment: #7A7672;
  --code-function: #E85D70;
  --code-number: #4A9FD8;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.2), 0 1px 3px rgba(0,0,0,0.15);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.3), 0 2px 4px rgba(0,0,0,0.2);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.4), 0 4px 12px rgba(0,0,0,0.25);
  --shadow-glass: 0 8px 32px rgba(0,0,0,0.3);
}

/* === 8套主题色切换 === */
[data-accent="purple"] {
  --brand-primary: #6B2D8F;
  --brand-hover: #4A1A6B;
  --brand-light: #E8D5F2;
  --brand-lighter: #F5EDFA;
  --border-focus: #6B2D8F;
}
[data-theme="dark"][data-accent="purple"] {
  --brand-primary: #B085D8;
  --brand-hover: #C49AE6;
  --brand-light: #2D1A40;
  --brand-lighter: #1E1028;
  --border-focus: #B085D8;
}

[data-accent="green"] {
  --brand-primary: #2E8B57;
  --brand-hover: #1A5F3C;
  --brand-light: #D4F1D4;
  --brand-lighter: #EDFAED;
  --border-focus: #2E8B57;
}
[data-theme="dark"][data-accent="green"] {
  --brand-primary: #4CAF7A;
  --brand-hover: #5EC98A;
  --brand-light: #1A3A28;
  --brand-lighter: #0F2218;
  --border-focus: #4CAF7A;
}

[data-accent="red"] {
  --brand-primary: #C41E3A;
  --brand-hover: #8B0A1A;
  --brand-light: #FADADD;
  --brand-lighter: #FDF2F3;
  --border-focus: #C41E3A;
}
[data-theme="dark"][data-accent="red"] {
  --brand-primary: #E85D70;
  --brand-hover: #F07080;
  --brand-light: #3A1A20;
  --brand-lighter: #281015;
  --border-focus: #E85D70;
}

[data-accent="brown"] {
  --brand-primary: #8B5A2B;
  --brand-hover: #5C3A1E;
  --brand-light: #F5E6D3;
  --brand-lighter: #FCF6EF;
  --border-focus: #8B5A2B;
}
[data-theme="dark"][data-accent="brown"] {
  --brand-primary: #C49A6C;
  --brand-hover: #D4AA7C;
  --brand-light: #3A2818;
  --brand-lighter: #281A0F;
  --border-focus: #C49A6C;
}

[data-accent="yellow"] {
  --brand-primary: #D4A017;
  --brand-hover: #8B6914;
  --brand-light: #FFF4CC;
  --brand-lighter: #FFFBE8;
  --border-focus: #D4A017;
}
[data-theme="dark"][data-accent="yellow"] {
  --brand-primary: #E8C547;
  --brand-hover: #F0D060;
  --brand-light: #3A3218;
  --brand-lighter: #28220F;
  --border-focus: #E8C547;
}

[data-accent="navy"] {
  --brand-primary: #10206B;
  --brand-hover: #0A1440;
  --brand-light: #C5D1E8;
  --brand-lighter: #E8ECF5;
  --border-focus: #10206B;
}
[data-theme="dark"][data-accent="navy"] {
  --brand-primary: #5A7FD4;
  --brand-hover: #7090E0;
  --brand-light: #1A2040;
  --brand-lighter: #0F1428;
  --border-focus: #5A7FD4;
}

[data-accent="mint"] {
  --brand-primary: #5E8B7E;
  --brand-hover: #3D5E55;
  --brand-light: #D5E8E3;
  --brand-lighter: #EDF5F2;
  --border-focus: #5E8B7E;
}
[data-theme="dark"][data-accent="mint"] {
  --brand-primary: #7AB8A8;
  --brand-hover: #8EC8B8;
  --brand-light: #1A3028;
  --brand-lighter: #0F2018;
  --border-focus: #7AB8A8;
}