*{
    margin : 0;
    padding: 0;
    box-sizing: border-box;
}
:root{
    --bg-color : #000; /* CSS variable */
    --bg-button-color : #1a1a1a;
    --bg-task-color : #2a2a2a;
    --primary-text-color : #f4f4f4;
    --delete-btn-bg-color : #ff4d4d;
    --blur-bg : rgba(50, 50, 50, 0.44);
    /* Padding variables */
    --nav-padding : 1rem 2rem;
    --section-padding : 1rem 2rem;
    --padding-s : 5px;
    --padding-m : 10px ;
    --padding-l :15px;
    --padding-xl : 20px;
    --padding-xxl : 30px;
    /* Margin Variables */
    --margin-s : 5px;
    --margin-m : 10px ;
    --margin-l :15px;
    --margin-xl : 20px;
    --margin-xxl : 30px;
    /* Border radius variables */
    --border-radius-s : 5px;
    --border-radius-m : 10px ;
    --border-radius-l :15px;
    --border-radius-xl : 20px;
    --border-radius-xxl : 30px;

}
html,
body{
    height: 100%;
    width: 100%;
}
html {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
}
body{
    background-color: var(--bg-color);
    color : var(--primary-text-color);
}
main{
    height: 100%;
    display: flex;
    flex-direction: column;
}
nav{
    padding: var(--nav-padding);
    display: flex;
    align-items: center;
    justify-content: space-between;
}
nav button {
    background-color: var(--bg-button-color);
    color: var(--primary-text-color);
    border: none;
    outline: none;
    padding: var(--padding-m) var(--padding-l);
    cursor: pointer;
    border-radius: var(--border-radius-m);
}

section{
    padding: var(--section-padding);
    display: flex;
    justify-content: space-between;
    flex-grow: 1;/* It covers rest empty area of parent element  make sure you have flex your parent element */
    gap: var(--padding-xxl);
}
section .task-column{
    flex-grow: 1;
    background-color: var(--bg-button-color);
    padding: var(--padding-m);
    display: flex;
    flex-direction: column;
    gap: var(--padding-m);
    border-radius: var(--border-radius-m);
    transition: all 0.2s cubic-bezier(0.19, 1, 0.22, 1);
}

section .task-column.hover-over{
    border: 2px dashed var(--primary-text-color);
    scale : 1.05;
    /* or transform : scale(1.05 */
}
section .task-column .heading{
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    
}
section .task-column  .task {
    background-color: var(--bg-task-color);
    border-radius: var(--border-radius-m);
    padding: var(--padding-m);
    display: flex;
    flex-direction: column;
    gap: var(--padding-s);
    cursor: grab;
}

section .task-column  .task button{
    align-self: flex-end;
    cursor: pointer;
    padding: var(--padding-m) var(--padding-l);
    border: none;
    outline: none;
    border-radius: var(--border-radius-m);
    background-color: var(--delete-btn-bg-color);
    color: var(--primary-text-color);
}

.modal {
    position: fixed;
    height: 100vh;
    width: 100vw;
    top: 0;
    left: 0;
    justify-content: center;
    align-items: center;
    display: none;
}

.modal.active{
    display: flex;
}

.modal .bg{
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    background-color:var(--blur-bg);
    backdrop-filter: blur(5px); /* It gives a blurry effect in the background*/
}

.modal .center {
    background-color:var(--bg-button-color);
    padding: var(--padding-xxl);
    border-radius: var(--border-radius-m);
    display: flex;
    flex-direction: column;
    gap: var(--padding-m);
    z-index: 10;
}
.modal .center input , .modal .center textarea {
    background-color: var(--bg-task-color);
    border: none;
    outline: none;
    color: var(--primary-text-color);
    padding: var(--padding-s);
    border-radius: var(--border-radius-s);
    resize: none; /* By using this textarea cannot be resized */
}
.modal .center button{
    background-color: var(--bg-task-color);
    border: none;
    outline: none;
    color: var(--primary-text-color);
    padding: var(--padding-m) var(--padding-xl);
    cursor: pointer;
    border-radius: var(--border-radius-m);
    width: fit-content; /*only takes widht in which it gets fit*/
    align-self: center;
}