:root{
    /* PALETA DE COLORES */
    --background-color:     #191919;
    --header-color:         #090909;
    --title1-color:         #38b6ff;
    --title2-color:         #5ce1e6;
    --panel-header-color:   #10438b;
    --fieldset-color:       #1e1e1e;
    --subtitle-color:       #d9d9d9;
    --text-color:           #fff;
    --button1-color:        #004aad;
    --button2-color:        #af0c0c;
    --placeholder-color:    #999;
    --text-color:           #fff;
    --text2-color:          #ddd;
    --input-color:          #333;
    --border-color:         #555;
    --row-color:            #252525;
    --footer-color:         #090909;

    /* REDONDEO */
    --corner1-radius:       0.75rem;
    --corner2-radius:       0.35rem;

    /* TAMANO TIPOGRAFIA */
    --main-title-size:      1.75rem;
    --legend-size:          0.85rem;
    --subtitle-size:        0.8rem;
    --text-size:            0.75rem;
}

/* RESETEAR ESPACIADO EN TODOS LOS COMPONENTES */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}    

body {
    background-color: var(--background-color);
    color: var(--text-color);
    font-family: "Roboto", Arial, Helvetica, sans-serif;
    display: flex;
    flex-direction: column;
    min-height: 100dvh;
    overflow-x: hidden;
}

/***************************************
             H E A D E R
***************************************/

header {
    background-color: var(--header-color);
    font-family: "Google Sans", Arial, Helvetica, sans-serif;
    padding: 0.85rem;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}    

h1{ font-size: var(--main-title-size); }

.MainTitle-1{ color: var(--title1-color); }    
.MainTitle-2{ color: var(--title2-color); }    

/***************************************
                M A I N
***************************************/

main {
    flex-grow: 1;
    padding: 0 clamp(2rem, 6vw, 3.5rem);
    width: 100%;
    margin: 0 auto;
}

fieldset {
    background-color: var(--fieldset-color);
    margin: 1.5rem 0;
    padding: 0.35rem 0.75rem 0.75rem 0.75rem;
    border: 0.12rem solid var(--border-color);
    border-radius: var(--corner1-radius);
    min-width: 100%;
}

legend {
    color: var(--title2-color);
    padding: 0 0.3rem;
    font-family: "Roboto", Arial, Helvetica, sans-serif;
    font-weight: 500;
    font-size: var(--legend-size);
}

th,h3,p{
    font-size: var(--subtitle-size);
    color: var(--text-color);
}

p{
    text-align: center;
}

.panel--initialIP{
    display: grid;
    grid-template-columns: 1fr 1rem 5rem;
    gap: 0.45rem;
    align-items: center;
}

.panel--subnets {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    position: relative;
}

.panel-header {
    display: grid;
    grid-template-columns: 1.4rem 11fr 5.2fr 2rem;
    gap: 0.5rem;
    background-color: var(--panel-header-color);
    padding: 0.6rem;
    border-radius: var(--corner2-radius);
}

.subnets-container {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 22.45rem);       
    min-height: 3rem;  
    overflow-y: auto;        
    gap: 0.5rem;
}

.subnets-container:empty {
    display: flex;
    align-items: center;
    justify-content: center;
    border:  0.12rem dashed var(--border-color);
    border-radius: var(--corner2-radius);
}

.subnets-container:empty::after {
    content: "Haz clic en 'Agregar' para crear subredes";
    color: var(--placeholder-color);
    font-size: var(--text-size);
    font-style: italic;
}

.subnets-input{
    display: grid;
    grid-template-columns: 1.6rem 8fr 4fr 2.45rem;
    gap: 0.5rem;
    align-items: center;
    margin-top: 0.35rem;
}

.subnets-input h3 {
    text-align: center;
    color: var(--subtitle-color)
}

.btn-container {
    margin-top: auto;         
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    width: 100%;
}

.radio-group {
    display: flex;
    justify-content: center; 
    gap: 2rem;             
    margin: 0.1rem 0;          
}

.radio-label {
    display: flex;
    align-items: center;     
    gap: 0.3rem;            
    cursor: pointer;        
    font-size: var(--subtitle-size);
    font-family: "Roboto", Arial, Helvetica, sans-serif;
    text-transform: uppercase;
    user-select: none; 
}

.radio-label input[type="radio"] {
    appearance: none;
    -webkit-appearance: none;
    background-color: var(--background-color); 
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid #ffffff;        
    border-radius: 50%;
    display: grid;
    place-content: center;           
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.radio-label input[type="radio"]::before {
    content: "";
    width: 0.65rem;
    height: 0.65rem;
    border-radius: 50%;
    transform: scale(0);
    transition: transform 0.15s ease-in-out;
    background-color: var(--title1-color); 
}

.radio-label input[type="radio"]:checked {
    border-color: var(--title1-color);
}

.radio-label input[type="radio"]:checked::before {
    transform: scale(1);
}

.radio-label:hover input[type="radio"] {
    border-color: var(--title2-color); 
}

.btn-group {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.7rem;
    width: 100%;
}

.subnets-container::-webkit-scrollbar,
.table-container::-webkit-scrollbar {
    width: 6px;
}
.table-container::-webkit-scrollbar:horizontal {
    height: 6px;
}

.subnets-container::-webkit-scrollbar-track, 
.table-container::-webkit-scrollbar-track {
    background: var(--background-color);
    border-radius: 4px;
}

.subnets-container::-webkit-scrollbar-thumb, 
.table-container::-webkit-scrollbar-thumb {
    background: var(--input-color);
    border-radius: 4px;
} 

.subnets-container::-webkit-scrollbar-thumb:hover, 
.table-container::-webkit-scrollbar-thumb:hover {
    background: #555;
}

input[type="text"],
input[type="number"] {
    background-color: var(--input-color);
    border: 1px solid var(--border-color);
    color: #fff;
    padding: 0.5rem;
    border-radius: var(--corner2-radius);
    font-family: "Roboto", Arial, Helvetica, sans-serif;
    font-size: var(--text-size);
    width: 100%;
    height: 2rem;
    transition: border-color 0.2s, box-shadow 0.2s;
}

input[type="text"]:focus,
input[type="number"]:focus {
    outline: none;
    border-color: var(--title1-color);
}

input::placeholder { color: var(--placeholder-color); }

.panel-output {
    display: none; 
    flex-direction: column;
}

.panel-output.visible-on-mobile {
    display: flex !important;
    margin-top: -1.6rem;
}

.panel--table {
    display: flex;
    flex-direction: column;
    overflow: hidden;
    gap: 0.75rem;
}

.txt-center{
    text-align: center !important;
}

.empty-msg{
    padding: 3rem !important;
    color: var(--placeholder-color) !important;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

.panel--table{
    overflow: hidden;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.table-container {
    overflow: auto;
    border-radius: var(--corner2-radius);
    flex-grow: 1;
}

table {
    border-collapse: separate; 
    border-spacing: 0;
    width: 100%;
}

thead {
    position: sticky;
    top: 0;
    z-index: 10;
}

th {
    background-color: var(--panel-header-color);
    color: var(--text-color);
    padding: 0.35rem 0.5rem;
    text-align: center;
    white-space: nowrap;
}

th:first-child { 
    border-top-left-radius: var(--corner2-radius); 
    border-bottom-left-radius: var(--corner2-radius); 
}
th:last-child { 
    border-top-right-radius: var(--corner2-radius); 
    border-bottom-right-radius: var(--corner2-radius); 
}

tbody tr {
    transition: background-color 0.15s;
}

tbody tr:nth-child(even) {
    background-color: var(--row-color);
}

tbody tr:hover {
    background-color: #ffffff0a;
}

td {
    padding: 0.6rem 0.5rem;
    text-align: left;
    border-bottom: 1px solid var(--input-color);
    font-size: var(--text-size);
    color: var(--text2-color);
    white-space: nowrap;
}

tr:last-child td {
    border-bottom: none;
}

button{
    background-color: var(--button1-color);
    font-family: "Google Sans", Arial, Helvetica, sans-serif;
    font-weight: 700;
    font-size: var(--subtitle-size);
    text-transform: uppercase;
    letter-spacing: 0.03rem;
    border: none;
    border-radius: var(--corner2-radius);
    transition: background-color 0.2s ease, transform 0.1s ease, filter 0.2s ease;
    user-select: none;
    color: var(--subtitle-color-color);
    padding: 0.65rem;
    cursor: pointer;
    display: inline-flex;
    justify-content: center;
    align-items: center;
}

button:hover {
    filter: brightness(1.45);
}

button:active {
    transform: scale(0.98);
    filter: brightness(0.75);
}

.btn-erase {
    background-color: var(--button2-color);
    width: 2rem;
    height: 2rem;
    font-size: var(--subtitle-color);
}

/***************************************
              F O O T E R
***************************************/

footer{
    text-align: center;
    background-color: var(--footer-color);
    border-top: 1px solid var(--border-color);
    font-size: var(--subtitle-size);
}

footer a {
    color: var(--title1-color);
    text-decoration: underline;
    font-weight: 500;
}

footer a:hover,
footer a:focus {
    color: var(--title2-color);
    text-decoration: none;
    outline: 2px solid var(--title2-color); 
}

.heart{
    color: var(--button2-color);
    filter: brightness(1.8);
    font-size: 1.1rem;
}

/***************************************
          R E S P O N S I V E 
***************************************/

@media (min-width: 60rem) {

    main {
        display: grid;
        grid-template-columns: 25rem 1fr; 
        gap: 1.85rem;          
        align-items: stretch;
        max-width: 95rem;
        padding: 0 3rem;   
        margin: 0 auto;
        overflow: hidden; 
    }

    .panel-input {
        display: flex;
        flex-direction: column;
        height: 100%;
        overflow: hidden;
    }
    
    .panel-input form {
        display: flex;
        flex-direction: column;
        height: 100%;
        overflow: hidden;
        justify-content: flex-start;
    }
    
    .panel--subnets {
        display: flex;
        flex-direction: column;
        flex-grow: 1; 
        height: auto;    
        margin-top: 0;   
        overflow: hidden;
    }

    .subnets-container {
        flex-grow: 1;         
        height: calc(100dvh - 24.5rem);     
        overflow-y: auto;   
    }

    .panel-output {
        display: flex;
        flex-direction: column;
        width: 100%;
        height: 100%;
        overflow: hidden;
        margin-top: 0rem !important; 
    }

    .panel--table {
        display: flex;
        flex-direction: column;
        height: 100%;
        overflow: hidden;
    }

    .table-container {
        flex-grow: 1;
        overflow-y: auto;  
        overflow-x: auto;   
    }

}