*{
margin:0;
padding:0;
box-sizing:border-box;
font-family:'Segoe UI',sans-serif;
scroll-behavior:smooth;
}

body{
background:linear-gradient(135deg,#c40000,#0a7d2c);
color:#fff;
overflow-x:hidden;
}

/* HERO HEADER CHUNG */
.hero{
height:100vh;
display:flex;
justify-content:center;
align-items:center;
flex-direction:column;
text-align:center;
background-size:cover;
background-position:center;
position:relative;
}

.hero::after{
content:"";
position:absolute;
top:0;
left:0;
width:100%;
height:100%;
background:rgba(0,0,0,0.5);
}

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

.hero h1{
font-size:77px;
text-shadow:2px 2px 10px black;
}

.hero p{
font-size:20px;
margin-top:10px;
}

/* Navbar */
nav{
position:fixed;
top:0;
width:100%;
background:rgba(0,0,0,0.7);
backdrop-filter:blur(10px);
padding:15px;
text-align:center;
z-index:1000;
}

nav a{
color:white;
margin:0 15px;
text-decoration:none;
font-weight:bold;
transition:0.3s;
}

nav a:hover{
color:yellow;
}

/* Header */
header{
height:100vh;
display:flex;
justify-content:center;
align-items:center;
flex-direction:column;
text-align:center;
}

header h1{
font-size:55px;
text-shadow:2px 2px 8px black;
}

.section{
padding:100px 10%;
background:rgba(255,255,255,0.1);
margin:40px 0;
border-radius:15px;
backdrop-filter:blur(15px);
opacity:0;
transform:translateY(50px);
transition:1s;
}

.section.show{
opacity:1;
transform:translateY(0);
}

.card{
margin:20px 0;
}

/* Gallery */
.gallery{
display:grid;
grid-template-columns:repeat(auto-fit,minmax(250px,1fr));
gap:20px;
}

.gallery img{
width:100%;
border-radius:15px;
cursor:pointer;
transition:0.4s;
}

.gallery img:hover{
transform:scale(1.05);
}

/* Button */
.btn{
background:#ffcc00;
color:black;
padding:10px 20px;
border:none;
border-radius:8px;
cursor:pointer;
font-weight:bold;
}

#topBtn{
position:fixed;
bottom:30px;
right:30px;
display:none;
}

/* Falling flowers */
.flower{
position:fixed;
top:-10px;
font-size:20px;
animation:fall linear infinite;
}

@keyframes fall{
to{
transform:translateY(100vh);
}
}

footer{
text-align:center;
padding:30px;
}

.hinh-truoctet{
    display:flex;
    gap:15px;              /* khoảng cách giữa hình */
    margin:15px 0;
}

.hinh-truoctet img{
    width:33.33%;          /* chia đều 3 hình */
    height:180px;
    object-fit:cover;      /* không méo ảnh */
    border-radius:10px;
    box-shadow:0 4px 8px rgba(0,0,0,0.2);
    transition:0.3s;
}

/* hiệu ứng hover */
.hinh-truoctet img:hover{
    transform:scale(1.05);
}

.hinh-sautet{
    margin:15px 0;
}

.hinh-sautet img{
    width:100%;
    height:750px;
    object-fit:cover;
    border-radius:12px;
    box-shadow:0 4px 10px rgba(0,0,0,0.2);
}

.amthuc{
    margin:40px 0;
}

.amthuc-item{
    display:flex;
    align-items:center;
    gap:25px;
    background:#fff;
    padding:20px;
    border-radius:15px;
    box-shadow:0 4px 10px rgba(0,0,0,0.1);
}

.amthuc-item img{
    width:200px;
    height:200px;
    object-fit:cover;   /* giữ hình không méo */
    border-radius:15px;
}

.amthuc-text h3{
    color:#c62828;
    margin-bottom:10px;
}

.amthuc-text p{
    font-size:16px;
    color:#555;
    line-height:1.6;
}

.amthuc-item img{
    transition:0.3s;
}

.amthuc-item img:hover{
    transform:scale(1.05);
}