/* ===============================
   CORE CSS – NỀN TOÀN HỆ THỐNG
   =============================== */

* {
    box-sizing: border-box;
}

html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}

body {
    background: #f4f8fb;
    font-family: 'Roboto', 'DM Sans', Arial, sans-serif;
    color: #333;
    line-height: 1.6;
}

/* ===============================
   TYPOGRAPHY
   =============================== */

h1, h2, h3, h4, h5 {
    color: #333;
    font-weight: 600;
}

h2 {
    letter-spacing: 1px;
    border-bottom: 3px solid #007bff;
    display: inline-block;
    padding-bottom: 5px;
    margin-bottom: 30px;
}

/* ===============================
   CONTAINER
   =============================== */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 15px;
}

/* ===============================
   GLOBAL FORM RESET
   =============================== */

input, button, select, textarea {
    font-family: inherit;
    font-size: 14px;
}

/* ===============================
   GLOBAL LINK
   =============================== */

a {
    color: #007bff;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}