:root {
    --concepto-primary: #FF6B00; /* Naranja principal */
    --concepto-secondary: #FFFFFF; /* Blanco */
    --concepto-dark: #2A2A2A; /* Fondo oscuro para tarjetas */
    --concepto-card: #FFFFFF; /* Color de las tarjetas - ahora blanco */
    --concepto-text: #333333; /* Color del texto principal - ahora oscuro */
    --concepto-text-secondary: #666666; /* Color del texto secundario */
    --concepto-border: #E0E0E0; /* Color de los bordes - más claro */
    --concepto-gradient: linear-gradient(135deg, #FF6B00 0%, #FF8533 100%); /* Gradiente naranja */
}

body {
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    min-height: 100vh;
    color: #333333;
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-weight: 400;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
}

h1 {
    font-weight: 700;
    font-size: 2.5rem;
    background: var(--concepto-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.card {
    background: var(--concepto-card);
    border: 1px solid var(--concepto-border);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    border-radius: 20px;
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(255, 107, 0, 0.15);
}

.card-header {
    background: transparent;
    border-bottom: 1px solid var(--concepto-border);
    font-weight: 600;
    font-size: 1.1rem;
    color: var(--concepto-primary);
    padding: 1.5rem;
}

.drop-area {
    border: 2px dashed var(--concepto-primary);
    border-radius: 16px;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: linear-gradient(135deg, rgba(255, 107, 0, 0.05) 0%, rgba(255, 133, 51, 0.02) 100%);
    position: relative;
    overflow: hidden;
    color: var(--concepto-text);
}

.drop-area h5, .drop-area p, .drop-area small {
    color: var(--concepto-text) !important;
}

.drop-area::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--concepto-gradient);
    opacity: 0;
    transition: opacity 0.3s ease;
    z-index: -1;
}

.drop-area:hover::before, .drop-area.dragover::before {
    opacity: 0.1;
}

.drop-area:hover, .drop-area.dragover {
    border-color: #FF8533;
    transform: scale(1.02);
    box-shadow: 0 8px 32px rgba(255, 107, 0, 0.3);
}

#fileSelect {
    color: var(--concepto-primary);
    text-decoration: none;
    font-weight: 600;
}

.btn-primary {
    background: var(--concepto-gradient);
    border: none;
    font-weight: 600;
    padding: 0.75rem 2rem;
    border-radius: 50px;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-size: 0.9rem;
}

.btn-primary:hover {
    background: linear-gradient(135deg, #E55A00 0%, #FF6B00 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 107, 0, 0.4);
}

.btn-secondary {
    background: transparent;
    border: 2px solid var(--concepto-border);
    color: var(--concepto-text);
    font-weight: 600;
    padding: 0.75rem 2rem;
    border-radius: 50px;
    transition: all 0.3s ease;
}

.btn-secondary:hover {
    background: var(--concepto-border);
    color: var(--concepto-text);
    transform: translateY(-2px);
}

.list-group-item {
    background: var(--concepto-card);
    border: 1px solid var(--concepto-border);
    color: var(--concepto-text);
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 15px;
    border-radius: 16px;
    padding: 1.25rem;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.list-group-item:hover {
    transform: translateX(5px);
    box-shadow: 0 4px 20px rgba(255, 107, 0, 0.15);
    border-color: rgba(255, 107, 0, 0.3);
}

.thumbnail {
    width: 80px;
    height: 80px;
    object-fit: cover;
    border-radius: 12px;
    cursor: pointer;
    transition: transform 0.3s ease;
}

.thumbnail:hover {
    transform: scale(1.05);
}

.image-info {
    flex-grow: 1;
    margin-left: 15px;
}

.image-info p {
    margin: 0;
    font-size: 0.9rem;
}

.image-info .filename {
    font-weight: 600;
    color: var(--concepto-text);
}

.image-info .date {
    font-size: 0.8rem;
    color: var(--concepto-text-secondary);
}

.btn-sm {
    margin-left: 5px;
}

.modal-content {
    background: var(--concepto-card);
    color: var(--concepto-text);
    border: 1px solid var(--concepto-border);
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
}

.modal-header, .modal-footer {
    border-color: var(--concepto-border);
}

.btn-close {
    filter: none;
}

.alert-info {
    background: linear-gradient(135deg, rgba(255, 107, 0, 0.15) 0%, rgba(255, 133, 51, 0.1) 100%);
    border: 1px solid rgba(255, 107, 0, 0.3);
    border-radius: 12px;
    color: var(--concepto-text);
    padding: 1rem 1.5rem;
}

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');