* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Roboto', sans-serif;
}

body {
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    min-height: 100vh;
    padding: 30px;
    color: #f0f0f0;
}

body > * {
    animation: aparecer 0.8s ease-out;
}

@keyframes aparecer {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

h2 {
    font-size: 18px;
    color: #00e5ff;
    margin-bottom: 25px;
    padding: 12px 18px;
    background: rgba(0, 229, 255, 0.1);
    border-left: 4px solid #00e5ff;
    border-radius: 8px;
    box-shadow: 0 0 15px rgba(0, 229, 255, 0.2);
    letter-spacing: 1px;
}

table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    margin: 30px 0;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease;
}

table:hover {
    transform: scale(1.01);
}

th {
    background: linear-gradient(90deg, #00b4d8, #0077b6);
    color: white;
    font-weight: bold;
    padding: 16px;
    text-transform: uppercase;
    letter-spacing: 1.2px;
    font-size: 15px;
}

td {
    padding: 15px;
    text-align: center;
    background: rgba(255, 255, 255, 0.95);
    color: #1a1a1a;
    border-bottom: 1px solid #e0e0e0;
    transition: all 0.3s ease;
}

tr:hover td {
    background: #caf0f8;
    color: #023e8a;
    transform: scale(1.02);
    font-weight: 500;
}

tr:nth-child(even) td {
    background: #f8fdff;
}

/* 3. Estilo para el ID mi-id: tamaño 20px, diseño destacado */
#mi-id {
    font-size: 20px;
    color: #ffd60a;
    font-weight: 600;
    margin: 25px 0;
    padding: 12px 20px;
    background: rgba(255, 214, 10, 0.12);
    border-radius: 30px;
    display: inline-block;
    box-shadow: 0 0 20px rgba(255, 214, 10, 0.3);
    border: 1px solid rgba(255, 214, 10, 0.4);
}

/* Botón con transición CORRECTA y efectos espectaculares */
.boton {
    background: linear-gradient(45deg, #ff0054, #ff5400);
    color: white;
    border: none;
    padding: 14px 30px;
    font-size: 17px;
    font-weight: 500;
    border-radius: 50px;
    cursor: pointer;
    box-shadow: 0 6px 18px rgba(255, 0, 84, 0.4);
    /* Transición en estado base ✅ */
    transition: all 0.5s ease;
    letter-spacing: 1px;
}

.boton:hover {
    background: linear-gradient(45deg, #7209b7, #3a0ca3);
    transform: translateY(-4px) scale(1.08);
    box-shadow: 0 10px 25px rgba(114, 9, 183, 0.5);
}

/* Flexbox para encabezado y pie ✅ */
header, footer {
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(90deg, #0077b6, #023e8a);
    color: white;
    padding: 20px;
    margin: 30px 0;
    border-radius: 12px;
    box-shadow: 0 6px 20px rgba(0, 119, 182, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.15);
}

header h1 {
    font-size: 26px;
    letter-spacing: 2px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

footer {
    background: linear-gradient(90deg, #1b263b, #0d1b2a);
    font-size: 15px;
    margin-top: 40px;
}

/* Grid para contenido principal ✅ */
main {
    display: grid;
    grid-template-columns: 3fr 1fr;
    gap: 25px;
    margin: 30px 0;
}

.contenido-principal {
    background: rgba(255, 255, 255, 0.95);
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.25);
    border-top: 5px solid #00b4d8;
    color: #1a1a1a;
    transition: transform 0.3s ease;
}

.contenido-principal:hover {
    transform: translateY(-3px);
}

.contenido-principal h3 {
    color: #023e8a;
    margin-bottom: 15px;
    font-size: 20px;
}

.barra-lateral {
    background: rgba(255, 255, 255, 0.9);
    padding: 22px;
    border-radius: 12px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.25);
    border-top: 5px solid #ffb703;
    color: #1a1a1a;
    transition: transform 0.3s ease;
}

.barra-lateral:hover {
    transform: translateY(-3px);
}

.barra-lateral h3 {
    color: #e67700;
    margin-bottom: 15px;
    font-size: 19px;
}