:root {
    --cor-texto: #1C2B39;
    --texto-suave: #445264;
    --cor-fundo: #EEF0F2;
    --cor-cartao: #FCFCFB;
    --cor-rascunho: #F5F3EE;
    --line: #D7DBE0;
    --borda-suave: #E4E7EA;
    --cor-principal: #1F5C4F;
    --principal-suave: rgba(31, 92, 79, 0.10);
    --cor-aviso: #8A5A3B;
    --radius: 3px;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    background: var(--cor-fundo);
    color: var(--cor-texto);
    font-family: 'IBM Plex Sans', sans-serif;
    -webkit-font-smoothing: antialiased;
}

.cabecalho {
    display: flex;
    align-items: center;
    padding: 18px 32px;
    border-bottom: 1px solid var(--cor-borda);
    background: var(--cor-cartao);
}

.logo-texto {
    margin: 0;
    font-family: 'Fraunces', serif;
    font-weight: 500;
    font-size: 22px;
    letter-spacing: 0.01em;
    color: var(--cor-texto);
}

.logo-texto span {
    color: var(--cor-principal);
    font-weight: bold;
}

.logo-icone {
    width: 26px;
    height: 26px;
    border: 1.5px solid var(--cor-texto);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Fraunces', serif;
    font-weight: 600;
    font-size: 14px;
}

.logo-texto {
    font-family: 'Fraunces', serif;
    font-weight: 500;
    font-size: 17px;
    letter-spacing: 0.01em;
}

.apresentacao {
    max-width: 760px;
    margin: 0 auto;
    padding: 64px 24px 8px;
    text-align: center;
 }

.apresentacao h1 {
    font-family: 'Fraunces', serif;
    font-weight: 500;
    font-size: clamp(30px, 4vw, 42px);
    line-height: 1.15;
    margin: 0 0 12px;
}

.apresentacao h1 em {
    font-style: italic;
    color: var(--cor-principal);
}

.apresentacao p {
    color: var(--texto-suave);
    font-size: 15.5px;
    margin: 0;
}

 /* controles */
.controles {
    max-width: 900px;
    margin: 40px auto 18px;
    padding: 0 24px;

    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.campo-select {
    position: relative;
    flex: 1;
    min-width: 220px;
}

.campo-select select {
    width: 100%;
}
select {
    appearance: none;
    -webkit-appearance: none;
    background: var(--cor-cartao);
    border: 1px solid var(--cor-texto);
    border-radius: var(--radius);
    padding: 9px 34px 9px 14px;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 13px;
    letter-spacing: 0.02em;
    color: var(--cor-texto);
    cursor: pointer;
}

.campo-select::after {
    content: "▾";
    position: absolute;
    right: 13px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 11px;
    pointer-events: none;
    color: var(--texto-suave);
}

/* paineis */
.paineis {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 24px;
    position: relative;
}

.grade-paineis {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0;
    border: 1px solid var(--cor-texto);
    background: var(--cor-cartao);
}

.painel {
    position: relative;
    padding: 20px 20px 16px;
    min-height: 260px;
    display: flex;
    flex-direction: column;
}

.painel-rascunho {
    background: var(--cor-rascunho);
    border-right: 1px dashed var(--line);
 }

.titulo-painel {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 10.5px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--texto-suave);
    margin-bottom: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.btn-icone {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--texto-suave);
    padding: 2px 4px;
    font-size: 14px;
    line-height: 1;
    transition: color .15s, opacity .15s;
}

.btn-icone:hover {
    color: var(--cor-texto);
}

#btnLimpar {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

#btnLimpar.visivel {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
}

.btn-icone:focus-visible,
select:focus-visible,
.btn-principal:focus-visible,
.btn-alteracoes:focus-visible {
    outline: 2px solid var(--cor-principal);
    outline-offset: 2px;
}

textarea {
    flex: 1;
    resize: none;
    border: none;
    background: transparent;
    width: 100%;
    min-height: 150px;
    font-size: 15px;
    line-height: 1.55;
    color: var(--cor-texto);
    padding: 0;
}

textarea:focus {
    outline: none;
}

#txtRascunho {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 14px;
}

#txtResultado {
    font-family: 'Fraunces', serif;
    font-size: 16.5px;
    color: var(--cor-texto);
}

#txtResultado.erro {
    color: var(--cor-aviso);
    font-family: 'IBM Plex Sans', sans-serif;
    font-style: italic;
}

textarea::placeholder {
    color: #9AA3AC;
}

.rodape-painel {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 14px;
}

.contador-char {
    font-family: 'IBM Plex Mono', monospace;
    font-size: 11.5px;
    color: var(--texto-suave);
}

.btn-principal {
    background: var(--cor-texto);
    color: var(--cor-cartao);
    border: none;
    border-radius: var(--radius);
    padding: 10px 20px;
    font-family: 'IBM Plex Sans', sans-serif;
    font-weight: 500;
    font-size: 13.5px;
    letter-spacing: 0.01em;
    cursor: pointer;
    transition: background .15s;
}

.btn-principal:hover {
    background: var(--cor-principal);
}

.btn-principal:disabled {
    background: #B7BEC5;
    cursor: not-allowed;
}

 /* alteracoes */
.alteracoes {
    max-width: 900px;
    margin: 0 auto;
    padding: 14px 24px 0;
    min-height: 20px;
}

 .btn-alteracoes {
    background: none;
    border: none;
    cursor: pointer;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 12.5px;
    color: var(--texto-suave);
    display: none;
    align-items: center;
    gap: 6px;
    padding: 4px 0;
}

.btn-alteracoes.visivel {
    display: flex;
}

.btn-alteracoes .seta {
    transition: transform .2s;
    display: inline-block;
}

.btn-alteracoes.aberto .seta {
    transform: rotate(90deg);
}

.lista-alteracoes {
    max-height: 0;
    overflow: hidden;
    transition: max-height .25s ease;
}

.lista-alteracoes.aberto {
    max-height: 200px;
}

.lista-alteracoes ul {
    margin: 10px 0 0;
    padding-left: 18px;
    font-size: 13.5px;
    color: var(--texto-suave);
    line-height: 1.8;
}

 /* about + footer */
.sobre {
    max-width: 900px;
    margin: 64px auto 0;
    padding: 24px 24px 0;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.sobre h2 {
    font-family: 'Fraunces', serif;
    font-weight: 500;
    font-size: 16px;
    margin: 20px 0 6px;
}

.sobre p {
    color: var(--texto-suave);
    font-size: 14px;
    line-height: 1.6;
    max-width: 560px;
}

footer {
    margin-top: 60px;
    padding: 20px 24px 40px;
    text-align: center;
    font-family: 'IBM Plex Mono', monospace;
    font-size: 11px;
    letter-spacing: .04em;
    color: var(--texto-suave);
}

footer a {
    color: inherit;
    text-decoration: none;
    border-bottom: 1px dotted currentColor;
    transition: opacity .2s;
}

footer a:hover {
    opacity: .7;
}

/* responsividade */

@media (max-width:720px) {
    .painel-rascunho {
        border-right: none;
        border-bottom: 1px dashed var(--line);
    }

    .controles {
        flex-direction: column;
    }

    .campo-select {
        width: 100%;
    }

    .grade-paineis {
        grid-template-columns: 1fr;
    }

}