/* =========================================
   1. VARIABLES GLOBALES (Design System)
   ========================================= */
:root {
    /* Paleta de Colores */
    --surface-container-lowest: #0e0e0f;
    --surface-container-high: #2a2a2b;
    --surface-container-highest: #353436;
    --surface-variant: #353436;
    --on-surface: #e5e2e3;
    --on-surface-variant: #bbc9cf;
    
    --primary: #a4e6ff;
    --primary-container: #00d1ff;
    --on-primary-fixed: #001f28;
    --on-primary-container: #00566a;
    
    --secondary-container: #7701d0;
    --secondary-fixed-dim: #dcb8ff;
    
    --outline: #859399;
    --outline-variant: #3c494e;
    
    /* Espaciados */
    --spacing-xs: 4px;
    --spacing-base: 8px;
    --spacing-sm: 12px;
    --spacing-gutter: 24px;
    --spacing-md: 24px;
    --spacing-lg: 48px;
    --spacing-xl: 80px;

    /* Tipografías */
    --font-headline: 'Space Grotesk', sans-serif;
    --font-body: 'Manrope', sans-serif;
}

/* =========================================
   2. RESET Y BASE
   ========================================= */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background-color: var(--surface-container-lowest);
    color: var(--on-surface);
    font-family: var(--font-body);
    font-size: 16px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* Colores de selección de texto */
::selection {
    background-color: var(--primary-container);
    color: var(--on-primary-container);
}

a {
    text-decoration: none;
    color: inherit;
}

.hidden {
    display: none !important;
}

/* =========================================
   3. EFECTOS DE FONDO (Blobs)
   ========================================= */
.bg-blobs {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}

.blob-primary, .blob-secondary {
    position: absolute;
    width: 50%;
    height: 50%;
    border-radius: 50%;
    filter: blur(120px);
}

.blob-primary {
    top: -10%;
    left: -10%;
    background-color: rgba(164, 230, 255, 0.1); /* primary/10 */
}

.blob-secondary {
    bottom: -10%;
    right: -10%;
    background-color: rgba(119, 1, 208, 0.1); /* secondary-container/10 */
}

/* =========================================
   4. LAYOUT PRINCIPAL (Grid)
   ========================================= */
.main-layout {
    position: relative;
    z-index: 10;
    width: 100%;
    max-width: 80rem; /* 1280px */
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-gutter);
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    align-items: center;
    flex-grow: 1;
}

/* Media Query para pantallas grandes (lg en Tailwind) */
@media (min-width: 1024px) {
    .main-layout {
        grid-template-columns: repeat(12, 1fr);
    }
    
    .hero-section {
        grid-column: span 7;
        display: flex;
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .login-section {
        grid-column: span 5;
        display: flex;
        justify-content: center;
    }
}

/* Ocultar el hero en móviles */
@media (max-width: 1023px) {
    .hero-section {
        display: none;
    }
}

/* =========================================
   5. COMPONENTES Y UTILIDADES
   ========================================= */
/* Glassmorphism */
.glass-panel {
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: inset 0 1px 1px rgba(255, 255, 255, 0.05), 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    border-radius: 12px;
}

/* Tipografía y Textos */
.text-gradient {
    background: linear-gradient(to right, var(--primary), var(--secondary-fixed-dim));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.text-gradient-brand {
    background: linear-gradient(to right, var(--primary-container), var(--secondary-container));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.heading-xl {
    font-family: var(--font-headline);
    font-size: 48px;
    font-weight: 700;
    line-height: 56px;
    letter-spacing: -0.02em;
}

.heading-lg {
    font-family: var(--font-headline);
    font-size: 32px;
    font-weight: 600;
}

.text-muted { color: var(--on-surface-variant); }
.text-small { font-size: 12px; font-weight: 600; letter-spacing: 0.05em; text-transform: uppercase; }

/* Botones */
.btn {
    display: flex;
    background-color: transparent;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm);
    border-radius: 8px;
    font-family: var(--font-body);
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    width: 100%;
}

.btn:active { transform: scale(0.95); }

.btn-social {
    background-color: var(--surface-container-high);
    border: 1px solid var(--outline-variant);
    color: var(--on-surface);
}

.btn-social:hover {
    background-color: var(--surface-container-highest);
}

.btn-social img { filter: grayscale(100%); transition: filter 0.2s; width: 20px; }
.btn-social:hover img { filter: grayscale(0%); }

.btn-login {
    background: linear-gradient(135deg, var(--primary-container) 0%, var(--secondary-container) 100%);
    color: var(--on-primary-fixed);
    font-family: var(--font-headline);
    font-size: 24px;
    box-shadow: 0 0 12px rgba(0, 209, 255, 0.3);
}

.btn-login:hover {
    box-shadow: 0 0 20px rgba(0, 209, 255, 0.5);
    transform: scale(1.01);
}

/* Formularios */
.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.input-wrapper {
    position: relative;
}

.input-icon {
    position: absolute;
    left: var(--spacing-md);
    top: 50%;
    transform: translateY(-50%);
    color: var(--outline);
}

.form-input {
    width: 100%;
    background-color: var(--surface-container-lowest);
    border: 1px solid var(--outline-variant);
    border-radius: 8px;
    padding: var(--spacing-sm) var(--spacing-md) var(--spacing-sm) var(--spacing-xl);
    color: var(--on-surface);
    font-family: var(--font-body);
    transition: all 0.2s;
}

.form-input:focus {
    outline: none;
    border-color: var(--primary-container);
    box-shadow: 0 0 0 1px var(--primary-container);
}

/* Separador (Divider) */
.divider {
    display: flex;
    align-items: center;
    margin-bottom: var(--spacing-lg);
}

.divider::before, .divider::after {
    content: "";
    flex-grow: 1;
    border-top: 1px solid var(--outline-variant);
}

.divider span {
    margin: 0 var(--spacing-md);
    color: var(--outline);
}

/* Footer */
.site-footer {
    width: 100%;
    padding: var(--spacing-lg) 0;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    margin-top: auto;
    position: relative;
    z-index: 60;
}

.footer-content {
    max-width: 80rem;
    margin: 0 auto;
    padding: 0 var(--spacing-gutter);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-links {
    display: flex;
    gap: var(--spacing-lg);
}

.footer-links a:hover { color: var(--primary-container); }

@media (max-width: 768px) {
    .footer-content { flex-direction: column; gap: var(--spacing-md); text-align: center; }
}
/* =========================================
   6. NAVEGACIÓN Y LAYOUT DE APLICACIÓN
   ========================================= */
.top-nav {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 50;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    background: rgba(10, 10, 11, 0.6);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 var(--spacing-md);
    height: 64px;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1);
}

.side-nav {
    position: fixed;
    left: 0;
    top: 64px;
    height: calc(100vh - 64px);
    width: 256px; 
    display: flex;
    flex-direction: column;
    padding: var(--spacing-md) var(--spacing-sm);
    background: rgba(10, 10, 11, 0.8);
    backdrop-filter: blur(40px);
    -webkit-backdrop-filter: blur(40px);
    border-right: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 40;
    box-shadow: 25px 0 50px -12px rgba(0, 0, 0, 0.25);
}

.nav-link {
    padding: var(--spacing-xs) var(--spacing-sm);
    color: var(--outline);
    transition: all 0.3s;
    font-weight: 500;
}

.nav-link:hover {
    color: var(--on-surface);
    background: rgba(255, 255, 255, 0.05);
    border-radius: 4px;
}

.nav-link.active {
    color: var(--primary-container);
    border-bottom: 2px solid var(--primary-container);
}

.side-nav-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm);
    border-radius: 8px;
    color: var(--outline);
    font-weight: 500;
    transition: all 0.2s;
    background: transparent;
    background-color: transparent;
    border: none;
    cursor: pointer;
    text-align: left;
    font-family: var(--font-headline);
}

.side-nav-btn:hover {
    color: var(--on-surface);
    background: rgba(255, 255, 255, 0.05);
}

.side-nav-btn.active {
    background: rgba(0, 209, 255, 0.1);
    color: var(--primary-container);
    border-right: 2px solid var(--primary-container);
}

/* Offset para el contenido cuando hay barra lateral */
.app-content {
    padding-top: 120px;
    padding-bottom: 80px;
}

/* CONTROL DE LAYOUT GLOBAL*/

/* Pantallas grandes (Escritorio) */
@media (min-width: 768px) {
    .app-content { 
        margin-left: 256px; 
    }
    .top-nav { 
        padding-left: calc(256px + var(--spacing-md)); 
    }
    .site-footer { 
        margin-left: 256px;
        width: calc(100% - 256px);
        z-index: 30;
    }
}

/* Pantallas pequeñas/ dispositivos moviles*/
@media (max-width: 767px) {
    .side-nav {
        display: none; /* Oculta la barra lateral en moviles */
    }
}

/* =========================================
   7. COMPONENTES ESPECÍFICOS DE LA PRÁCTICA
   ========================================= */
.upload-zone {
    border: 2px dashed var(--outline-variant);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    overflow: hidden;
    transition: border-color 0.3s;
}

.upload-zone:hover {
    border-color: var(--primary-container);
}

/* Progress Bar */
.progress-container {
    height: 4px;
    width: 100%;
    background-color: var(--surface-container-highest);
    border-radius: 99px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-container) 0%, var(--secondary-container) 100%);
    box-shadow: 0 0 8px var(--primary-fixed-dim);
}

/* Radio Buttons Nativos Estilizados */
.radio-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-xs);
}

.radio-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    cursor: pointer;
    color: var(--on-surface);
    font-size: 14px;
    font-weight: 500;
}

.radio-label input[type="radio"] {
    appearance: none; /* Oculta el radio nativo del navegador */
    width: 18px;
    height: 18px;
    border: 2px solid var(--outline-variant);
    border-radius: 50%;
    background-color: transparent;
    cursor: pointer;
    position: relative;
    transition: all 0.2s;
}

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

.radio-label input[type="radio"]:checked::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: var(--primary-container);
}

/* Custom Select */
.custom-select {
    width: 100%;
    background-color: transparent;
    color: var(--on-surface);
    border: none;
    font-family: var(--font-body);
    font-weight: 500;
    outline: none;
    cursor: pointer;
}

.custom-select option {
    background-color: var(--surface-container-high);
}

/* Waveform Bars */
.waveform {
    display: flex;
    align-items: flex-end;
    gap: 4px;
    height: 120px;
}

.wave-bar {
    flex: 1;
    border-radius: 99px;
}
/* =========================================
   8. ESTADOS DINÁMICOS Y ANIMACIONES (JSP)
   ========================================= */
/* Estado Deshabilitado (Antes de subir la canción) */
.disabled-panel {
    opacity: 0.3;
    pointer-events: none; /* Evita clics */
    filter: grayscale(100%);
    transition: all 0.5s ease;
}

/* Rueda de carga (Spinner) */
.loader {
    border: 4px solid rgba(255, 255, 255, 0.1);
    border-top: 4px solid var(--primary-container);
    border-radius: 50%;
    width: 48px;
    height: 48px;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-sm) auto;
}
@keyframes spin { 
    0% { transform: rotate(0deg); } 
    100% { transform: rotate(360deg); } 
}

/* Botón de Preview (Estilo Spotify) */
.preview-btn {
    background: transparent;
    border: none;
    color: var(--primary);
    cursor: pointer;
    transition: transform 0.2s, color 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}
.preview-btn:hover {
    transform: scale(1.2);
    color: var(--primary-container);
}

/* Mosaico Iniciar Práctica (Estilo Hyprland) */
.tile-btn {
    border: 1px solid rgba(255, 255, 255, 0.1);
    background: linear-gradient(135deg, rgba(0, 209, 255, 0.05) 0%, rgba(119, 1, 208, 0.05) 100%);
    transition: all 0.3s ease;
}
.tile-btn:hover:not(.disabled-panel) {
    background: linear-gradient(135deg, rgba(0, 209, 255, 0.15) 0%, rgba(119, 1, 208, 0.15) 100%);
    border-color: var(--primary-container);
    transform: translateY(-2px);
    box-shadow: 0 10px 30px -10px rgba(0, 209, 255, 0.3);
}

/* =========================================
   10. PÁGINA DE BIENVENIDA (LANDING)
   ========================================= */

/* Hero Section */
.hero-container {
    position: relative;
    min-height: 90vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 var(--spacing-md);
    overflow: hidden;
}

.hero-content {
    position: relative;
    z-index: 10;
    max-width: 64rem;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.hero-title {
    font-size: clamp(3rem, 5vw, 4rem);
    line-height: 1.1;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    font-family: var(--font-headline);
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--on-surface-variant);
    max-width: 42rem;
    margin-bottom: var(--spacing-lg);
    line-height: 1.6;
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 4px 16px;
    border-radius: 99px;
    border: 1px solid rgba(164, 230, 255, 0.2);
    color: var(--primary);
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    background: rgba(255, 255, 255, 0.03);
}

.btn-group {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
    justify-content: center;
}

.btn-large {
    padding: 16px 32px;
    font-size: 18px;
    border-radius: 12px;
}

.btn-outline {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--on-surface);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.05);
}

.btn-white {
    background: var(--on-surface);
    color: var(--surface-container-lowest);
    border-radius: 99px;
}

.btn-white:hover {
    background: var(--primary);
}

/* Bento Grid */
.bento-section {
    padding: var(--spacing-xl) var(--spacing-md);
    background: var(--surface-container-lowest);
}

.bento-container {
    max-width: 80rem;
    margin: 0 auto;
}

.bento-header {
    margin-bottom: var(--spacing-lg);
}

.bento-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

@media (min-width: 768px) {
    .bento-grid {
        grid-template-columns: repeat(12, 1fr);
    }
}

.bento-card {
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: 24px;
    padding: var(--spacing-md);
    transition: border-color 0.3s;
    overflow: hidden;
}

.bento-card:hover {
    border-color: rgba(164, 230, 255, 0.3);
}

.bento-span-8 { grid-column: span 8; }
.bento-span-4 { grid-column: span 4; }
.bento-span-5 { grid-column: span 5; }
.bento-span-7 { grid-column: span 7; }

.bento-flex-row {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

@media (min-width: 768px) {
    .bento-flex-row {
        flex-direction: row;
    }
}

/* CTA Section */
.cta-section {
    padding: var(--spacing-xl) var(--spacing-md);
    position: relative;
}

.cta-card {
    max-width: 56rem;
    margin: 0 auto;
    padding: var(--spacing-xl);
    border-radius: 32px;
    border: 1px solid rgba(0, 209, 255, 0.2);
    text-align: center;
    position: relative;
    overflow: hidden;
}

/* =========================================
   11. TARJETAS DE PRÁCTICA (myPractices.jsp)
   ========================================= */

/* Grid Responsivo */
.practice-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    margin-top: var(--spacing-md);
}

@media (min-width: 640px) { .practice-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .practice-grid { grid-template-columns: repeat(3, 1fr); } }
@media (min-width: 1536px) { .practice-grid { grid-template-columns: repeat(4, 1fr); } }

/* Tarjeta Individual */
.practice-card {
    position: relative;
    display: flex;
    flex-direction: column;
    padding: 16px;
    transition: all 0.4s ease;
    cursor: pointer;
}

.practice-card:hover {
    border-color: rgba(0, 209, 255, 0.4);
    transform: translateY(-4px);
    box-shadow: 0 10px 30px -10px rgba(0, 209, 255, 0.15);
}

/* =========================================
   ANIMACIÓN DEL BOTÓN ELIMINAR (TARJETAS)
   ========================================= */

/* Cambiamos a Flexbox para que la animación de empuje fluya a 60 FPS */
.card-stats-grid {
    display: flex;
    gap: 16px;
    align-items: center;
    width: 100%;
}

.stat-box {
    flex: 1; /* Esto hace que los recuadros se encojan automáticamente al ser empujados */
    /* Tus estilos de fondo y bordes actuales se mantienen intactos */
}

/* El contenedor nace con ancho 0 y oculto para que los recuadros ocupen el 100% */
.delete-action-wrapper {
    width: 0;
    opacity: 0;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1); /* Curva suave de animación */
}

/* Al hacer hover en toda la tarjeta, el contenedor crece a la derecha y empuja la UI */
.practice-card:hover .delete-action-wrapper {
    width: 48px; /* El tamaño exacto del botón */
    opacity: 1;
    margin-left: 8px; /* Un pequeño respiro visual para separarlo de la precisión */
}

/* Diseño moderno del botón basurero */
.btn-delete {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    border: 1px solid rgba(255, 74, 74, 0.3);
    background: rgba(255, 74, 74, 0.1);
    color: #ff4a4a;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-delete:hover {
    background: rgba(255, 74, 74, 0.2);
    border-color: #ff4a4a;
    transform: scale(1.05);
}

/* Imagen y Overlay */
.card-image-wrapper {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 9;
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: var(--spacing-sm);
}

.card-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.7s ease;
}

.practice-card:hover .card-image {
    transform: scale(1.1);
}

.card-gradient-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
}

.card-badge {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 4px 8px;
    border-radius: 4px;
    background: rgba(0, 209, 255, 0.9);
    color: #000;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.card-play-btn {
    position: absolute;
    bottom: 12px;
    left: 12px;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(12px);
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Meta y Estadísticas */
.card-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-sm);
}

.card-tag {
    background: rgba(255, 255, 255, 0.05);
    padding: 2px 8px;
    border-radius: 4px;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.card-stats-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin-bottom: var(--spacing-sm);
}

.stat-box {
    background: rgba(14, 14, 15, 0.5);
    border-radius: 8px;
    padding: 8px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    text-align: center;
}

/* Nueva Práctica (Placeholder) */
.new-practice-card {
    border: 2px dashed rgba(255, 255, 255, 0.15);
    border-radius: 16px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--outline);
    cursor: pointer;
    transition: all 0.3s;
    min-height: 280px;
}

.new-practice-card:hover {
    border-color: var(--primary-container);
    color: var(--primary-container);
    background: rgba(0, 209, 255, 0.05);
}

/* Efectos visuales */
.wave-gradient {
    background: linear-gradient(90deg, #00d1ff 0%, #7701d0 100%);
}

.progress-container-small {
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 99px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    border-radius: 99px;
}

/* Botones Superiores */
.filter-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    border-radius: 8px;
    background: var(--surface-container-high);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--on-surface-variant);
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
}

.filter-btn:hover {
    border-color: var(--primary-container);
    color: var(--on-surface);
}

.heading-md {
    font-family: var(--font-headline);
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* =========================================
   NUEVOS ESTILOS PARA LA BATERÍA 3D
   ========================================= */
:root {
    --tertiary: #ffcdfa;
    --primary-container: #00d1ff;
}

.perspective-view {
    perspective: 1000px;
}

.highway-track {
    transform: rotateX(45deg);
    transform-origin: bottom;
    border-left: 1px solid rgba(255,255,255,0.05);
    border-right: 1px solid rgba(255,255,255,0.05);
    background: linear-gradient(to top, rgba(164, 230, 255, 0.05), transparent);
}

.glow-cyan { box-shadow: 0 0 20px rgba(76, 214, 255, 0.4); }
.glow-purple { box-shadow: 0 0 20px rgba(220, 184, 255, 0.4); }

/* Animación de golpe en los tambores */
.drum-pad {
    transition: all 0.05s ease-out; /* Súper rápido para que se sienta responsivo */
}
.drum-pad.active {
    transform: scale(1.15) translateY(-10px);
    filter: brightness(1.5);
}
.drum-pad.active-kick { box-shadow: 0 0 40px var(--tertiary); border-color: var(--tertiary); }
.drum-pad.active-snare { box-shadow: 0 0 40px var(--secondary); border-color: var(--secondary); }
.drum-pad.active-hihat { box-shadow: 0 0 40px var(--primary); border-color: var(--primary); }

/* Lógica de navegación colapsable */
.side-nav {
    transition: transform 0.3s ease-in-out;
}
.side-nav.collapsed {
    transform: translateX(-100%);
}
.practice-arena {
    transition: all 0.3s ease-in-out;
}
.practice-arena.expanded {
    left: 0 !important;
    width: 100vw !important;
}