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

body{
    font-family: Arial, Helvetica, sans-serif;
    background: var(--background-color);
    color: var(--text-color);
}

/* HEADER */

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

    padding:20px 60px;

    background: var(--secondary-color);
    color:var(--white);
}

.logo img{
    height:50px;
    width:auto;
}

nav a{
    margin-left:20px;
    text-decoration:none;
    color:var(--white);
    font-weight:500;
}

nav a:hover{
    color:var(--primary-color);
}


/* BANNER */

.banner img{
    width:100%;
    height:auto;
    display:block;
}


/* PRODUCTS */

.products{
    max-width:var(--container-width);
    margin:auto;
    padding:60px 20px;
}

.products h2{
    text-align:center;
    margin-bottom:40px;
}

.product-list{
    display:grid;

    grid-template-columns:repeat(3,1fr);

    gap:30px;
}

/* PRODUCT CARD */

.product{
    background:var(--white);
    padding:20px;
    border-radius:var(--border-radius);
    text-align:center;

    box-shadow:0 2px 10px rgba(0,0,0,0.08);

    transition:var(--transition);
}

.product:hover{
    transform:translateY(-5px);
}

.product img{
    width:100%;
    height:220px;
    object-fit:cover;
    margin-bottom:15px;
}

.product h3{
    margin-bottom:10px;
}

.product p{
    font-weight:bold;
    color:var(--primary-color);
    margin-bottom:15px;
}

/* BUTTON */

button{
    padding:10px 20px;
    border:none;
    background:var(--primary-color);
    color:var(--white);
    border-radius:var(--border-radius);

    cursor:pointer;

    transition:var(--transition);
}

button:hover{
    background:#3b866f;
}


/* FOOTER */

.footer{
    background:#111;
    color:white;
    margin-top:40px;
}

.footer-container{
    max-width:1200px;
    margin:auto;
    padding:40px 20px;

    display:flex;
    justify-content:space-between;
    flex-wrap:wrap;
    gap:30px;
}

.footer-col h3{
    margin-bottom:10px;
}

.footer-col h4{
    margin-bottom:10px;
}

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

.slogan{
    font-style:italic;
}

.footer-bottom{
    text-align:center;
    padding:15px;
    border-top:1px solid #333;
    font-size:14px;
}

/* ================= AUTH (LOGIN / REGISTER) ================= */

.auth{
    width:350px;
    margin:100px auto;
    background:var(--white);
    padding:40px 30px;

    border-radius:var(--border-radius);

    box-shadow:0 5px 20px rgba(0,0,0,0.1);

    text-align:center;
}

.auth h2{
    margin-bottom:25px;
}

.auth input{
    width:100%;
    padding:12px;
    margin-bottom:15px;

    border:1px solid #ddd;
    border-radius:var(--border-radius);

    font-size:14px;
}

.auth input:focus{
    outline:none;
    border-color:var(--primary-color);
}

.auth button{
    width:100%;
    margin-top:5px;
}

.auth p{
    margin-top:15px;
    font-size:14px;
}

.auth a{
    color:var(--primary-color);
    text-decoration:none;
    font-weight:500;
}

.auth a:hover{
    text-decoration:underline;
}

/* ================= CART ================= */

.cart{
    max-width:900px;
    margin:60px auto;
    padding:20px;
}

#cart-items{
    margin-bottom:30px;
}

/* mỗi sản phẩm trong giỏ */
.cart-item{
    display:flex;
    align-items:center;
    justify-content:space-between;

    background:var(--white);
    padding:15px;
    margin-bottom:15px;

    border-radius:var(--border-radius);

    box-shadow:0 2px 8px rgba(0,0,0,0.08);
}

.cart-item img{
    width:80px;
    height:80px;
    object-fit:cover;
    border-radius:6px;
}

.cart-info{
    flex:1;
    margin-left:20px;
}

.cart-info h4{
    margin-bottom:5px;
}

.cart-info p{
    color:var(--primary-color);
    font-weight:bold;
}

.cart-remove{
    background:#e74c3c;
}

.cart-remove:hover{
    background:#c0392b;
}

.cart h3{
    margin-bottom:15px;
}

/* ================= CHECKOUT ================= */

.checkout{
    width:400px;
    margin:80px auto;

    background:var(--white);
    padding:40px;

    border-radius:var(--border-radius);

    box-shadow:0 5px 20px rgba(0,0,0,0.1);
}

.checkout h2{
    text-align:center;
    margin-bottom:25px;
}

.checkout input{
    width:100%;
    padding:12px;
    margin-bottom:15px;

    border:1px solid #ddd;
    border-radius:var(--border-radius);
}

.checkout input:focus{
    outline:none;
    border-color:var(--primary-color);
}

.checkout button{
    width:100%;
}

.product-detail{
    max-width:1000px;
    margin:60px auto;
    display:flex;
    gap:40px;
    padding:20px;
}
    
.product-detail img{ 
    width:400px;
    border-radius:8px;   
}
    
.detail-info{  
    flex:1; 
}
    
.detail-info h2{
    margin-bottom:15px;
}
    
.detail-info p{
    margin-bottom:15px;
}
    
.detail-info button{
    margin-top:10px;
}

.cart-item{

    display:flex;
    justify-content:space-between;
    align-items:center;
    
    background:white;
    padding:15px;
    margin-bottom:10px;
    
    border-radius:6px;
    box-shadow:0 2px 6px rgba(0,0,0,0.1);
    
    }
    
    .qty{
    
    display:flex;
    align-items:center;
    gap:10px;
    
    }
    
    .qty button{
    
    width:30px;
    height:30px;
    
    border:none;
    background:#333;
    color:white;
    
    border-radius:4px;
    
    cursor:pointer;
    
    }
    
    .cart-item button{
    
    border:none;
    background:rgb(125, 191, 211);
    color:white;
    
    padding:5px 10px;
    
    border-radius:4px;
    
    cursor:pointer;
    
    }