/* --- ESTILOS GLOBALES Y VARIABLES DE TEMA --- */
:root {
    --bg-color-dark: #121212;
    --surface-color-dark: #1e1e1e;
    --primary-color-dark: #bb86fc;
    --text-color-dark: #e0e0e0;
    --border-color-dark: #333;
    --bg-color-light: #f5f5ff;
    --surface-color-light: #ffffff;
    --primary-color-light: #007bff;
    --text-color-light: #212529;
    --border-color-light: #dee2e6;
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --border-radius: 8px;
    --box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}
[data-theme="dark"] {
    --bg-color: var(--bg-color-dark);
    --surface-color: var(--surface-color-dark);
    --primary-color: var(--primary-color-dark);
    --text-color: var(--text-color-dark);
    --border-color: var(--border-color-dark);
}
[data-theme="light"] {
    --bg-color: var(--bg-color-light);
    --surface-color: var(--surface-color-light);
    --primary-color: var(--primary-color-light);
    --text-color: var(--text-color-light);
    --border-color: var(--border-color-light);
}
body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}
header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 2rem;
    background-color: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--box-shadow);
}
.logo { max-height: 50px; }
h1 { font-size: 1.5rem; margin: 0; color: var(--primary-color); text-align: center; }
.theme-button { background: none; border: none; color: var(--text-color); font-size: 1.5rem; cursor: pointer; }
.main-container {
    display: flex;
    justify-content: center;
    align-items: center;
    flex: 1;
    padding: 2rem;
}
footer { text-align: center; padding: 1rem; background-color: var(--surface-color); border-top: 1px solid var(--border-color); width: 100%; margin-top: auto; }

/* --- ESTILOS GENERALES PARA TARJETAS Y FORMULARIOS --- */
.info-card { background-color: var(--surface-color); padding: 2rem 2.5rem; border-radius: var(--border-radius); box-shadow: var(--box-shadow); border: 1px solid var(--border-color); text-align: center; max-width: 500px; width: 100%; transition: background-color 0.3s, border-color 0.3s; }
.form-group { margin-bottom: 2rem; text-align: left;}
label { display: block; margin-bottom: 0.5rem; font-weight: bold; }
.generate-button { width: 100%; padding: 0.8rem; font-size: 1.2rem; font-weight: bold; color: #fff; background-color: var(--primary-color); border: none; border-radius: var(--border-radius); cursor: pointer; transition: background-color 0.2s; display: flex; align-items: center; justify-content: center; gap: 0.75rem;}
.generate-button:hover { opacity: 0.9; }

/* --- ESTILOS HERRAMIENTA GENERADOR QR --- */
.qr-card { max-width: 500px; }
.tab-container { display: flex; border-bottom: 1px solid var(--border-color); margin-bottom: 1.5rem; }
.tab-button { flex: 1; padding: 0.8rem 1rem; cursor: pointer; background: none; border: none; color: var(--text-color); opacity: 0.6; font-size: 1rem; font-weight: bold; border-bottom: 3px solid transparent; transition: all 0.3s ease; display: flex; align-items: center; justify-content: center; gap: 0.5rem; }
.tab-button:hover { opacity: 1; background-color: var(--bg-color); }
.tab-button.active { opacity: 1; color: var(--primary-color); border-bottom-color: var(--primary-color); }
.tab-content { display: none; }
.tab-content.active { display: block; }
.qr-card input, .qr-card select, .qr-card textarea { width: 100%; padding: 0.7rem; font-size: 1rem; border: 1px solid var(--border-color); border-radius: var(--border-radius); background-color: var(--bg-color); color: var(--text-color); box-sizing: border-box; }
.qr-card textarea { resize: vertical; }
.qr-result-container {
    display: none;
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
}
#qr-canvas {
    border-radius: var(--border-radius);
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}
#download-qr-link { width: auto; padding: 0.6rem 1.5rem; display: inline-flex; }

/* --- SECCIÓN DE RESPONSIVIDAD (Media Queries) --- */
@media (max-width: 550px) {
    .main-container { padding: 1rem; }
    header { display: grid; grid-template-columns: auto 1fr auto; align-items: center; padding: 0.75rem 1rem; gap: 1rem; }
    h1 { font-size: 1.15rem; }
    .info-card, .generator-card, .qr-card { padding: 1.5rem; }
}