:root {
    --primary-color: #a61c2f;      /* Rojo oscuro, base */
    --primary-light: #d63447;      /* Rojo más claro, para acentos */
    --secondary-color: #0f4c3a;    /* Verde oscuro, institucional */
    --accent-color: #d4af37;       /* Dorado/mostaza, toque elegante */
    --accent-light: #e6c066;       /* Dorado más claro, para fondos suaves */
    --text-dark: #1a1a1a;          /* Texto oscuro */
    --text-light: #666666;         /* Texto gris */
    --background-light: #f9f9f9;   /* Fondo claro y neutro */
    --white: #ffffff;              /* Blanco puro */
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);  /* Sombra estándar */
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    background-color: var(--background-light);
    color: var(--text-dark);
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: #000;
    z-index: 1000;
    padding: 1rem 0;
}

.header-text {
    color: var(--white);
    font-size: 1.2rem;
    font-weight: 500;
    text-align: right;
    padding-right: 2rem;
    letter-spacing: -0.5px;
}

.nav-bar {
    background-color: var(--white);
    padding: 1rem 2rem;
    box-shadow: var(--shadow);
    display: flex;
    gap: 1rem;
    position: sticky;
    top: 3.5rem;
    z-index: 100;
}

.nav-bar a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-bar a:hover {
    color: var(--primary-light);
}

.spreadsheet-button {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: white !important;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.3s ease;
}

.spreadsheet-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(166, 28, 47, 0.2);
    color: white !important;
}

.container {
    max-width: 1200px;
    margin: 6rem auto 2rem;
    padding: 0 2rem;
}

section {
    background: var(--white);
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
}

h1, h2 {
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}

h1 {
    font-size: 2.5rem;
    border-bottom: 3px solid var(--primary-light);
    padding-bottom: 0.5rem;
}

.emphasis-description {
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 2rem;
}

/* Stream Cards */
.streams-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin: 2rem 0;
    perspective: 1000px;
}

.stream-card {
    position: relative;
    min-height: 400px;
    transform-style: preserve-3d;
    transition: transform 0.8s;
    cursor: pointer;
}

.stream-card.flipped {
    transform: rotateY(180deg);
}

.stream-card__front,
.stream-card__back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: 15px;
    padding: 2rem;
}

.stream-card__front {
    background: linear-gradient(145deg, var(--primary-color), var(--primary-light));
    color: var(--white);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.stream-card__back {
    background: linear-gradient(145deg, var(--primary-light), var(--accent-color));
    color: var(--white);
    transform: rotateY(180deg);
    overflow-y: auto;
}

.stream-card__icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
}

.stream-card h3 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    color: var(--white);
}

.stream-card p {
    font-size: 1rem;
    line-height: 1.6;
    margin-bottom: 1rem;
}

.stream-card__back p {
    text-align: justify;
    margin-bottom: 1rem;
}

/* Phases Section */
.phases-container {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
    margin-top: 2rem;
}

.phase {
    background: var(--white);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
    position: relative;
}

.phase-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-light);
    opacity: 0.3;
    position: absolute;
    top: 1rem;
    right: 1rem;
}

/* Methodology Section */
.methodology-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}

.methodology-card {
    background: var(--background-light);
    border-radius: 12px;
    padding: 2rem;
    border-left: 4px solid var(--primary-color);
}

.methodology-card h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* Image Carousel */
.image-carousel {
    margin-top: 4rem;
    padding: 2rem;
    background: var(--white);
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.carousel-container {
    position: relative;
    max-width: 800px;
    margin: 2rem auto;
    overflow: hidden;
}

.carousel-card {
    display: none;
    position: relative;
    width: 100%;
    height: 400px;
    margin: 0 auto;
    perspective: 1000px;
    cursor: pointer;
    transition: transform 0.6s;
}

.carousel-card__front {
    position: absolute;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(145deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    border-radius: 15px;
    backface-visibility: hidden;
    transition: opacity 0.6s;
}

.carousel-card__front h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.carousel-card__content {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 0.6s;
    border-radius: 15px;
    overflow: hidden;
}

.carousel-card__content img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 15px;
}

.carousel-card:hover .carousel-card__front {
    opacity: 0;
}

.carousel-card:hover .carousel-card__content {
    opacity: 1;
}

.carousel-nav {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 2rem;
}

.prev-btn,
.next-btn {
    background: var(--primary-color);
    color: var(--white);
    border: none;
    padding: 1rem 2rem;
    font-size: 1.5rem;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.prev-btn:hover,
.next-btn:hover {
    background: var(--primary-light);
    transform: translateY(-2px);
}

.prev-btn:active,
.next-btn:active {
    transform: translateY(1px);
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem;
    background: #000;
    color: var(--white);
    margin-top: 4rem;
}

.footer-title {
    font-weight: 700;
    color: var(--white);
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

footer p {
    margin: 0.5rem 0;
    color: #86868b;
    font-size: 0.9rem;
    text-align: center;
}

footer a {
    color: var(--accent-light);
    text-decoration: none;
    transition: color 0.3s ease;
}

footer a:hover {
    color: var(--white);
}

/* Responsive Design */
@media (max-width: 1200px) {
    .streams-container {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .phases-container {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }
    
    .streams-container,
    .methodology-grid {
        grid-template-columns: 1fr;
    }
    
    .phases-container {
        grid-template-columns: 1fr;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    .carousel-card {
        height: 300px;
    }
}

.code-container {
    padding-top: 40px;
    height: 100%;
    text-align: center;
}

#code {
    width: 770px;
    height: 350px;
    resize: none;
    background-color: rgb(73, 70, 92);
    border-radius: 5px;
    border: none;
    color: white;
    padding: 10px;
}

#code:focus {
    outline: none !important;
}

.key-point {
    padding: 2rem;
    background: var(--background-light);
    border-radius: 8px;
    transition: transform 0.3s ease;
    border-left: 4px solid var(--primary-color);
}