html {
    scroll-behavior: smooth;
}

body {
    font-size: 18px;
    line-height: 1.8em;
    color: #515151;
    font-family: Arial, '微軟正黑體', '新細明體', Helvetica, sans-serif;

}

section {
    padding: 2em 1.5em;
}


.jumbotron {
    height: 50vh;
    background: url(../img/kvbg.jpg) center no-repeat;
    background-size: cover;
    margin-bottom: 0;
}

.kv-main-title {
    font-size: 3.6rem;
    font-weight: 600;
    color: #fff;
    text-shadow: rgba(0, 0, 0, 0.8) 0px 3px 8px;
    margin-top: 8%;
    text-align: center;
}

.kv-sub-title {
    font-size: 2.7rem;
    font-weight: 600;
    color: #81ba2f;
    text-shadow: rgba(0, 0, 0, 0.8) 0px 3px 8px;
    margin-top: 1em;
    text-align: center;
    
}


nav {
    font-weight: 800;
    box-shadow: 0 0 3px rgb(0 0 0 / 20%);
    letter-spacing: 4px;
    color: #3ec430;

}

.navbar {
    padding: 0px 5vw;
    margin: 0px;
}

.navbar-brand img {
    max-width: 75%;
}

.navbar-nav {
    width: 100%;
}



.nav-link {
    padding: 20px 40px;
    transition: transform 0.2s ease, color 0.2s ease;
    border-radius: 8px;
}

.nav-link:hover {
    transform: translate(2px, 1px);

}

h1 {
    font-size: 3.2em;
    font-weight: 600;
    text-align: center;
    color: #fff;
    text-shadow: rgba(0, 0, 0, 0.8) 0px 3px 8px;
    margin-top: 2em;
}

.txt-green {
    color: #76b900;

}

a {
    color: #EC6604;
}

a:hover {
    color: #FEA82F;
    text-decoration: none;
}

.btn-main {
    background-color: #76b900;
    border-color: #76b900;
    padding: 15px 20px;
    border-radius: 30px;
    margin-bottom: 10px;
}

.btn-main:hover {
    background-color: #4B8500;
    border-color: #4B8500;
}


.section-foreword {
    color: #fff;
    background-color: #16161a;
}

.foreword-title {
    color: #e04010;
    font-weight: 700;
    margin-bottom: 2rem;
    line-height: 1.8;
    text-align: center;
    font-size: 2.2em;
}


.foreword-info {
    background-color: #fff;
    padding: 10px;
    margin-bottom: 30px;
    color: #121212;
    font-size: 20px;
}


.main-title {
    font-size: 2.8rem;
    color: #242629;
    text-align: center;
    font-weight: 700;
    margin-bottom: 2rem;
}


.four-box {
    padding: 20px;
    border-radius: 10px;
    background-color: #74b71b;
    margin-bottom: 25px;
}



.section-agenda {
    background-color: #f1f1f1;
}

.section-agenda ul li {
    font-size: 15px;
    line-height: 1.8;
}

.sp-info {
    border-left: 2px solid #76b900;
    padding-left: 10px;
    margin: 15px 0;
}

.sp-name {
    color: #16161a;
    font-size: 1.5rem;
}

.sp-desc {
    color: #94a1b2;
}

.read-more {
    color: #ec9b01;
}

.read-more:hover {
    color: #EC6604;
    text-decoration: none;
}

.collapse-txt {
    font-size: 16px;
}

.collapse-title {
    font-weight: 700;
    color: #000;
}

.section-tech {
    background-color: #16161a;
}



.section-date {
    padding: 5em 0;
    background-size: cover;
    background: url(../img/background.jpg);
    background-attachment: fixed;

}



.date-box {
    background-color: rgba(255, 255, 255, 0.8);
    padding: 30px 40px;
    text-align: center;
    color: #121212;
    /* border: 3px solid #ff6a00; */
}


.date-box h3 {
    font-size: 1.8em;
    font-weight: 700;
    line-height: 1.5;
}

.date-box p {
    margin: 20px 0 0;
    font-size: 20px;
}





/*sponsor*/

.level-block-title {
    color: #333;
    font-weight: 700;
    text-align: center;
    margin: 20px 0 10px;
}

.level-block img {
    max-width: 250px;
}

footer {
    color: #fff;
    background-color: #121212;
    font-size: 16px;
    padding: 1% 0;
    line-height: 1.4em;
}



/*sidebar*/
#sidebarReg .register {
    background-color: #74b71b;
    color: #fff;
    position: fixed;
    bottom: 15%;
    right: 0;
    border: none;
    display: block;
    font-weight: bold;
    font-size: 20px;
    writing-mode: vertical-lr;
    padding: 25px 10px;
    z-index: 10;
    border-radius: 10px 0 0 10px;
    box-shadow: 2px 3px 8px 0px rgba(58, 15, 228, 0.32);
}

#sidebarReg .register:hover {
    background-color: #C0E972;
}

#gotopBtn {
    display: none;
    /* Hidden by default */
    position: fixed;
    /* Fixed/sticky position */
    bottom: 20px;
    /* Place the button at the bottom of the page */
    right: 30px;
    /* Place the button 30px from the right */
    z-index: 99;
    /* Make sure it does not overlap */
    border: none;
    /* Remove borders */
    outline: none;
    /* Remove outline */
    background-color: rgba(121, 182, 0, 0.5);
    color: #fff;
    cursor: pointer;
    /* Add a mouse pointer on hover */
    padding: 10px 20px;
    border-radius: 50px;
    font-size: 18px;
}

#gotopBtn:hover {
    background-color: rgba(121, 182, 0, 0.8);
}

:target:before {
    content: "";
    display: block;
    height: 72px;
    /* fixed header height*/
    margin: -72px 0 0;
    /* negative fixed header height */
}




/* form */

help-block {
    display: block;
    margin-top: 5px;
    margin-bottom: 10px;
    color: #737373;
}