/* ==========================================================================
   MHENT STUDY - CORE THEME & DESIGN TOKENS
   Đồng bộ tiêu chuẩn MHEnt Universe (Dark/Light Glassmorphism & Cyber Modern)
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800;900&family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=Noto+Sans+KR:wght@400;500;700&family=Noto+Sans+JP:wght@400;500;700&family=Noto+Sans+SC:wght@400;500;700&display=swap');

:root {
    /* ☀️ Light Mode */
    --bg-primary: #f8fafc;
    --bg-surface: #ffffff;
    --bg-glass: rgba(255, 255, 255, 0.85);
    --bg-glass-strong: rgba(255, 255, 255, 0.96);
    --bg-subtle: #f1f5f9;

    --border-color: rgba(226, 232, 240, 0.8);
    --border-glass: rgba(255, 255, 255, 0.6);

    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;

    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.07);
    --shadow-glass: 0 8px 32px rgba(14, 165, 233, 0.08);

    /* MHEnt Accent Colors */
    --accent-edu: #0ea5e9;
    --accent-edu-glow: rgba(14, 165, 233, 0.35);
    --accent-korea: #ec4899;
    --accent-japan: #ef4444;
    --accent-china: #f59e0b;
    --accent-english: #6366f1;

    --success: #10b981;
    --success-bg: rgba(16, 185, 129, 0.12);
    --error: #ef4444;
    --error-bg: rgba(239, 68, 68, 0.12);
    --warning: #f59e0b;

    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-full: 9999px;

    --transition-fast: 0.2s cubic-bezier(0.16, 1, 0.3, 1);
    --transition-normal: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

/* 🌙 Dark Mode (Default MHEnt aesthetic) */
body.dark-mode {
    --bg-primary: #07090e;
    --bg-surface: #0f172a;
    --bg-glass: rgba(15, 23, 42, 0.82);
    --bg-glass-strong: rgba(15, 23, 42, 0.95);
    --bg-subtle: #1e293b;

    --border-color: rgba(51, 65, 85, 0.7);
    --border-glass: rgba(255, 255, 255, 0.08);

    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;

    --shadow-sm: 0 2px 10px rgba(0, 0, 0, 0.5);
    --shadow-md: 0 12px 40px rgba(0, 0, 0, 0.6);
    --shadow-glass: 0 10px 40px rgba(0, 0, 0, 0.7);
}

/* Base Reset */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Plus Jakarta Sans', 'Noto Sans KR', 'Noto Sans JP', 'Noto Sans SC', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Outfit', sans-serif;
    font-weight: 700;
    line-height: 1.25;
}

a {
    color: inherit;
    text-decoration: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
    outline: none;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--accent-edu);
}