*{
    padding: 0;
    margin: 0;
    box-sizing: border-box;
}

body {
    overflow-x: hidden;
}

/* ---------- nav ---------- */
.nav {
    position: fixed;
    top: 0;
    z-index: 100;
}

.nav ul {
    background-color: black;
    opacity: 0.7;
    list-style-type: none;
    display: flex;
    width: 100vw;
    justify-content: center;
    align-items: center;
}

.nav li a{
    color: #fff;
    display: block;
    text-decoration: none;
    padding: 20px;
}

.nav li a:hover {
    background-color: white;
    color: black;
}

/* -------- basis page setting --------- */

.page {
    width: 100%;
    min-height: 100vh;
    padding: 65px 12%;
    background-color: #CED4DA;
    border-bottom: 3px solid transparent;
    border-image: linear-gradient(to left, lightcyan, #87CEEB, #4682B4, #33ccff , #3366ff) 1;
}

#course {
    border-bottom: none;
}

.page-title {
    font-size: 70px;
    text-align: center;
}

/* -------- homepage --------- */

.home-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
}

.home-content h1 {
    margin-bottom: 20px;
    font-size: 75px;
}

.home-content h3 {
    font-size: 35px;
    margin-bottom: 15px;
}

.homepage-link {
    display: flex;
    justify-content: center;
    height: 50px;
    gap: 40px;
}

.home-content img {
    width: 40px;
    transition: width 0.5s;
}

.home-content img:hover {
    width: 50px;
}

/* ----------- About me --------- */

#about {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.about-row {
    flex: 1;
    display: flex;
    align-items: center;
    height: 100%;
}

.text-col {
    flex-basis: 50%;
    font-size: 24px;
    text-align: justify;
}

.img-col {
    flex-basis: 50%;
}

.img-col img {
    display: block;
    margin: auto;
}

.text-col h2 {
    font-size: 50px;
}

/* --------- Skilla ----------- */

#skills {
    display: flex;
    flex-direction: column;
}

.skill-content {
    display: flex;
    flex-wrap: wrap;
    align-content: center;
    justify-content: center;
    flex: 1;
    gap: 20px;
}

.skill-block {
    background-color: rgba(152, 156, 154, 0.1);
    color:#1E3A8A;
    border: 1px solid black;
    padding: 10px 20px;
    font-size: 30px;
    border-radius: 30px;
    font-weight: 600;
    transition: background-color 0.3s color 0.3s;
    user-select: none;
}

.skill-block:hover {
    background-color: lightcoral;
}

/* -------------- courses --------------- */

#courses {
    display: flex;
    flex-direction: column;
}

#courses table {
    border: 1px solid black;
    border-spacing: 0;
    border-radius: 15px;
    overflow: hidden;
    flex: 1;
}

#courses th, #courses td {
    border: 1px solid black;
    padding: 10px 20px;
}