* {margin:0; padding:0; box-sizing:border-box;}
        body {font-family: Arial, sans-serif; line-height:1.6; color:#333; padding-top: 100px;}
        a {text-decoration:none;}
        ul {list-style:none;}

        html {scroll-behavior: smooth;}
                                              /* ==== Header ==== */
header {
    background: #fff; box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05); position: fixed; top: 0; left: 0; width: 100%; z-index: 1000;}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 20px 60px;
}

/* LOGO */

.logo img {
    height: 60px;
    display: block;
}

/* DESKTOP MENU */

.nav-links {
    display: flex;
    align-items: center;
    gap: 40px;

    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-links a {
    color: #1a2036;
    font-weight: 500;
    text-decoration: none;

    transition: color 0.3s;
}

.nav-links a:hover {
    color: #c07d56;
}

/* HAMBURGER BUTTON - DESKTOP ДЭЭР НУУНА */

.hamburger {
    display: none;

    width: 44px;
    height: 44px;

    padding: 10px;

    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 6px;

    background: transparent;
    border: none;
    cursor: pointer;
}

.hamburger span {
    display: block;

    width: 25px;
    height: 2px;

    background: #1a2036;
    border-radius: 2px;

    transition: transform 0.3s ease,
                opacity 0.3s ease;
}

/* SECTION SCROLL OFFSET */

section {
    scroll-margin-top: 120px;
}


/* =========================
   MOBILE VERSION
========================= */

@media screen and (max-width: 768px) {

    /* HEADER SIZE */

    .navbar {
        padding: 12px 20px;
    }

    .logo img {
        height: 45px;
    }

    /* HAMBURGER ХАРУУЛНА */

    .hamburger {
        display: flex;
        position: relative;
        z-index: 1002;
    }

    /* MOBILE MENU */

    .nav-links {
        position: fixed;

        top: 0;
        right: 0;

        width: 300px;
        max-width: 85vw;
        height: 100vh;
        height: 100dvh;

        padding: 100px 30px 40px;

        background: #fff;
        box-shadow: -5px 0 25px rgba(0, 0, 0, 0.08);

        display: flex;
        flex-direction: column;
        align-items: flex-start;
        justify-content: flex-start;

        gap: 0;

        overflow-y: auto;

        transform: translateX(100%);
        visibility: hidden;

        transition: transform 0.35s ease,
                    visibility 0.35s ease;

        z-index: 1001;
    }

    /* MENU LINKS */

    .nav-links li {
        width: 100%;

        border-bottom: 1px solid #eeeeee;
    }

    .nav-links a {
        display: block;
        width: 100%;

        padding: 17px 0;

        font-size: 16px;
    }

    .nav-links a:hover {
        color: #c07d56;
    }

    /* MENU OPEN */

    .nav-links.active {
        transform: translateX(0);
        visibility: visible;
    }

    /* HAMBURGER -> X */

    .hamburger.active span:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    /* BACKGROUND SCROLL LOCK */

    body.menu-open {
        overflow: hidden;
    }

}

                                                      /* ==== Hero ==== */
#hero{
position:relative;
height:100vh;
display:flex;
align-items:center;
justify-content:center;
text-align:center;
overflow:hidden;
color:#fff;
}

/* background layer */

.hero-bg{
position:absolute;
top:0;
left:0;
width:100%;
height:120%;
background-image:url('hero-bg.png');
background-size:cover;
background-position:center;
z-index:-3;
}

/* gradient overlay */

.hero-overlay{
position:absolute;
top:0;
left:0;
width:100%;
height:100%;

z-index:-2;
}

/* text */

.hero-content{
position:relative;
z-index:2;
}

.hero-content h1{
font-size:3em;
margin-bottom:20px;
text-shadow:
0 2px 4px rgba(0,0,0,0.4),
0 6px 20px rgba(0,0,0,0.4);
}

.hero-content p{
margin-bottom:30px;
text-shadow:
0 2px 4px rgba(0,0,0,0.4),
0 6px 20px rgba(0,0,0,0.4);
}

.hero-btn{
display:inline-block;
padding:12px 30px;
background:#fff;
color:#3480e2;
font-weight:bold;
border-radius:30px;
transition:0.3s;
}

.hero-btn:hover{
background:#3480e2;
color:#fff;
}

                                   /* ==== Organization Section ==== */
#index-organization {
    padding: 200px 20px;
    background: #f9f9f9;
}
.org-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    align-items: center; 
    gap: 40px;
}
.org-image img {
    width: 100%;
    max-width: 500px; 
    border-radius: 10px;
}
.org-text {
    flex: 1;
}
.org-text h2 {
    font-size: 2em;
    margin-bottom: 20px;
}
.org-text p {
    font-size: 1.1em;
    line-height: 1.6;
}
/* Organization Button */
.org-btn {
    display: inline-block;
    margin-top: 20px;
    padding: 12px 25px;
    background: #3480e2;
    color: #fff;
    font-weight: bold;
    border-radius: 30px;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: none;
}
.org-btn:hover {
    background: #3480e2; 
    color: #fff;
    transform: translateY(2px);
    box-shadow: inset 0 4px 6px rgba(0,0,0,0.3);
}

                                          /* ==== Lessons ==== */
        #lessons{
            padding:80px 20px;
            max-width:1400px;
            margin:0 auto;
        }
        #lessons h2{
            text-align:center;
            margin-bottom:60px;
            font-size:2em;
        }

        .lesson-grid{
            display:grid;
            grid-template-columns:repeat(auto-fit,minmax(200px,1fr));
            gap:30px;
        }

        .lesson-card{
            background:#fff;
            border-radius:15px;
            overflow:hidden;
            box-shadow:0 10px 30px rgba(0,0,0,0.08);
            transition:0.3s;
        }

        .lesson-card:hover{
            transform: scale(1.05);
            box-shadow:0 15px 40px rgba(0,0,0,0.3);
        }
        .lesson-card:hover img{
            transform:scale(1.1);
        }

        .lesson-card img{
            width:100%;
            height: auto;
            object-fit:contain;
            transition: transform 0.3s;
        }

        .lesson-content{
            padding:20px;
            text-align:center;
            position:relative;
        }

        .lesson-content h3{
            margin-bottom:10px;
            color:#1a2036;
        }

        .lesson-content p{
            font-size:0.9em;
            color:#666;
        }
        
        /* текст */

        .lesson-text{
transition:opacity 0.3s ease;
}

/* button */

.lesson-btn{
position:absolute;
left:50%;
top:60%;
transform:translate(-50%,-50%);
padding:2px 20px;
border-radius:25px;
color:#fff;
font-size:14px;
font-weight:600;
background:#3480e2;
opacity:0;
pointer-events:none;
transition:all 0.3s ease;
}
.lesson-btn:hover {
    box-shadow: inset 0 4px 6px rgba(0,0,0,0.3);
}

/* hover effect */

.lesson-card:hover .lesson-text{
opacity:0;
}

.lesson-card:hover .lesson-btn{
opacity:1;
pointer-events:auto;
}

                                            /* ==== Peace Letters ==== */
#letters {
    padding: 200px 20px;
    max-width: 1500px;
    margin: 0 auto;
}
#letters h2 {
    text-align: center;
    margin-bottom: 40px;
}

.letter-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px,1fr));
    gap: 20px;
}

.letter-card {
    cursor: pointer;
    overflow: hidden;
    border-radius: 15px;
    transition: transform 0.3s, box-shadow 0.3s;
}
.letter-card img {
    width: 100%;
    height: auto;
    display: block;
    object-fit: cover;
    transition: transform 0.3s;
}
.letter-card:hover {
    transform: scale(1.05);
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
}
.letter-card:hover img{
transform:scale(1.1);
}

/* ==== Lightbox ==== */
#lightbox {
    position: fixed;
    top:0; left:0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.8);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
}
#lightbox.show {
    opacity: 1;
    pointer-events: auto;
}
#lightbox img {
    max-width: 90%;
    max-height: 90%;
    border-radius: 15px;
    transition: transform 0.3s ease;
}
#close {
    position: absolute;
    top: 20px;
    right: 40px;
    font-size: 40px;
    color: #fff;
    cursor: pointer;
}

                                         /* ==== Footer ==== */
footer{
background:#1a2036;
color: #fff;
padding:60px 20px 20px;
}

.footer-container{
max-width:1200px;
margin:auto;
display:grid;
grid-template-columns:repeat(auto-fit,minmax(250px,1fr));
gap:40px;
}

.footer-col h3{
margin-bottom:20px;
}

.footer-col p{
line-height:1.6;
color:#ccc;
}

.footer-col ul li{
margin-bottom:10px;
}

.footer-col ul li a{
color:#ccc;
transition:0.3s;
}

.footer-col ul li a:hover{
color:#f06f24;
}

.social-icons{
display:flex;
gap:15px;
margin-top:10px;
}

.social-icons a{
width:40px;
height:40px;
display:flex;
align-items:center;
justify-content:center;
background:#2b3155;
color:#fff;
border-radius:50%;
font-size:18px;
transition:0.3s;
}

.social-icons a:hover{
background:#f06f24;
transform:translateY(-3px);
box-shadow: 0 10px 10px rgba(0,0,0,0.3);
}

.footer-bottom{
text-align:center;
margin-top:40px;
padding-top:20px;
border-top:1px solid rgba(48, 48, 48, 0.38);
color:#aaa;
}
                                       /* ==== Reveal ==== */
/* SECTION animation */

.reveal-fade{
opacity:0;
transition:all 0.5s ease;
}

.reveal-fade.active{
opacity:1;
}

.reveal-up {
  opacity: 0;
  transform: translateY(50px);
  transition: all 1s ease;
}
.reveal-up.active {
  opacity: 1;
  transform: translateY(0);
}

.reveal-down {
  opacity: 0;
  transform: translateY(-50px);
  transition: all 1s ease;
}
.reveal-down.active {
  opacity: 1;
  transform: translateY(0);
}

.reveal-herotext {
  opacity: 0;
  transform: translateY(50px);
  transition: all 2s ease;
}
.reveal-herotext.active {
  opacity: 1;
  transform: translateY(0);
}

/* CARD animation */

.lesson-card,
.letter-card{
opacity:0;
transform:translateY(-30px);
transition:all 0.6s ease;
}

.lesson-card.active,
.letter-card.active{
opacity:1;
transform:translateY(0);
}



                                              /* ==== Responsive ==== */
        @media (max-width:1024px){

    .lesson-grid{
        grid-template-columns: repeat(2,1fr);
    }

    .letter-grid{
        grid-template-columns: repeat(2,1fr);
    }

    .org-container{
        flex-direction: column;
        text-align: center;
    }

    .org-image img{
        max-width: 80%;
    }

}

@media (max-width:768px){

header{
    flex-direction: column;
    padding:15px;
}

.nav-menu{
    flex-direction: column;
    gap:10px;
    margin-top:10px;
}

.hero{
    padding:100px 20px;
    text-align:center;
}

.hero h1{
    font-size:28px;
}

.hero p{
    font-size:16px;
}

.lesson-grid{
    grid-template-columns:1fr;
}

.letter-grid{
    grid-template-columns:1fr;
}

.lesson-card img{
    width:100%;
    height:auto;
}

}

@media (max-width:480px){

.hero h1{
    font-size:24px;
}

.hero p{
    font-size:14px;
}

.org-btn{
    padding:10px 18px;
    font-size:14px;
}

.lesson-card{
    padding:10px;
}

}