.idea-section {
    background-color: var(--cor-fundo-principal);
    padding: 15vh 5vw;
    display: flex;
    align-items: center;
    justify-content: center;
}

.idea-card-container {
    width: 530px;
    height: 265px;
    position: relative;
    perspective: 2000px;
    border-radius: 12px;
}

.idea-card-front,
.idea-card-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden; 
    transition: transform 1s cubic-bezier(0.68, -0.55, 0.27, 1.55), 
                border 1s cubic-bezier(0.68, -0.55, 0.27, 1.55);
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.1); 
    outline: none;
}

/* --- A "Capa" (Visão Fechada) --- */
.idea-card-front {
    background: radial-gradient(circle, var(--cor-borda-sutil), var(--cor-fundo-principal));
    color: var(--cor-texto-principal); 
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-family: var(--fonte-sans, sans-serif);
    cursor: pointer;
    z-index: 2; 
    transform: rotateY(0deg); 
}

.idea-card-front i {
    font-size: 4rem;
    margin-bottom: 1rem;
}
.idea-card-front span {
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.idea-card-back {
    background: var(--cor-fundo-card-claro); 
    color: var(--cor-texto-card-escuro); 
    padding: 35px;
    transform: rotateY(180deg);
}
.content h3 {
    font-family: var(--fonte-serif, serif);
    font-size: 2rem;
    margin-bottom: 1rem;
}
.content p {
    font-family: var(--fonte-sans, sans-serif);
    font-size: 1rem;
    line-height: 1.6;
}

.close-idea-card {
    position: absolute;
    top: 15px;
    right: 15px;
    cursor: pointer;
    width: 25px;
    height: 25px;
    opacity: .6;
    transition: opacity 0.3s ease;
}
.close-idea-card:hover { opacity: 1; }
.close-idea-card::before, .close-idea-card::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--cor-texto-card-escuro); 
}
.close-idea-card::before { transform: rotate(45deg); }
.close-idea-card::after { transform: rotate(-45deg); }

.idea-card-container.is-flipped .idea-card-front {
    transform: rotateY(-180deg);
    border: 1px solid transparent;
}

.idea-card-container.is-flipped .idea-card-back {
    transform: rotateY(0deg); 
}

body.light-theme .idea-card-back .content h3 {
    color: var(--cor-titulo-serif); 
}

body.light-theme .idea-card-back .close-idea-card::before,
body.light-theme .idea-card-back .close-idea-card::after {
    background: var(--cor-texto-principal);
}

body.light-theme .idea-card-front {
    background: var(--cor-fundo-card-claro); 
    color: var(--cor-texto-principal);
    border: 1px solid var(--cor-borda-sutil); 
}

body.light-theme .idea-card-front i,
body.light-theme .idea-card-front span {
    color: var(--cor-texto-principal);
}