* {
    /* sau này đỡ tính toán width để cộng thêm border padding  */
    box-sizing: border-box;
}

html,
body {
    scroll-behavior: smooth;
    font-family: "Montserrat", sans-serif;
}

html {
    font-size: 62.5%;
    background: #c0392b; /* fallback for old browsers */
    background: -webkit-linear-gradient(
        to right,
        #8e44ad,
        #c0392b
    ); /* Chrome 10-25, Safari 5.1-6 */
    background: linear-gradient(
        to right,
        #8e44ad,
        #c0392b
    ); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
    font-family: "Montserrat", sans-serif;
}

.content {
    /* nếu bình thường mà độ rộng lớn hơn 1110px thì hiện bth */
    width: 1110px;
    /* nếu như nhỏ hơn thì nó sẽ ăn theo max-width */
    max-width: calc(100%-48px);
    margin-left: auto;
    margin-right: auto;
}

a {
    text-decoration: none;
    color: #fff;
}

/* ======= Header ======= */
header {
    padding-top: 110px;
    font-size: 2.75rem;
    display: flex;
    justify-self: center;
}
.navbar {
    display: flex;
    justify-content: center;
    font-family: "Open Sans", sans-serif;
    border-radius: 999px;
    border: 1px solid #fff;
    background-color: rgba(255, 255, 255, 0.2);
    margin-left: auto;
    margin-right: auto;
}

header .content {
    width: 70%;
    min-width: 1110px;
}

.navbar ul {
    justify-content: center;
    width: 100%;
    display: flex;
    gap: 10%;
    padding: 15px 0;
}

.navbar ul a {
    position: relative;
    /* margin-left: 50px; */
    padding: 5px 10px;
    color: #fff;
}

ul > li > a::before {
    content: "";
    position: absolute;
    width: 85%;
    height: 3px;
    background-color: #fff;
    border-radius: 999px;
    transform: scaleX(0);
    transition: all 0.5s ease-in-out;
    bottom: 0;
    left: 10%;
}
.navbar li:hover > a::before {
    transform: scaleX(0.5);
}

/* ============ Hero =========== */

main {
    margin-top: 80px;
}

.title {
    font-size: 5rem;
    color: #fff;
    font-weight: 600;
    letter-spacing: 1;
    text-align: center;
}

.hero {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 130px auto;
    min-height: 100px;
    height: 20vh;
    width: 42vw;
    min-width: 1110px;
    min-width: 1110px;
    padding-bottom: 75px;
}
.hero::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 30px;
    background: radial-gradient(
        ellipse at center,
        rgba(0, 0, 0, 0.2) 0%,
        rgba(0, 0, 0, 0) 70%
    );
    filter: blur(5px);
    z-index: 1;
}

.hero .instruction {
    text-align: right;
    /* margin-left: 120px; */
    font-size: 2.75rem;
    margin-right: 20px;
    max-width: 300px;
    color: #fff;
    line-height: 3.5rem;
}

.hero .logo-apache {
    margin-right: 20px;
    /* max-width: 400px;
    width: 30%; */
    min-height: 150px;
    height: 15vh;
    max-height: 250px;
    align-items: center;
    padding: 0 4%;
    background-color: #fff;
    border-radius: 25px;
}

.banquyen {
    position: absolute;
    bottom: 0.7%;
    left: 50%;
    font-size: 1.75rem;
    color: #fff;
    transform: translateX(-50%);
}

.banquyen strong {
    font-weight: 600;
}
/* ======= scroll ======== */

::-webkit-scrollbar {
    border-radius: 0;
    width: 8px;
}

::-webkit-scrollbar-thumb {
    border-radius: 4px;
    background-color: rgba(22, 24, 35, .2);
}

::-webkit-scrollbar-track {
    border-radius: 0;
    background-color: rgba(0, 0, 0, 0);
}