/* --- Variables de Color y Tipografía --- */
:root {
    --font-primary: 'Lato', sans-serif;
    --font-headings: 'Poppins', sans-serif;
    
    /* Modo Claro (Default) */
    --color-bg: #f4f7f9;
    --color-text: #333;
    --color-card-bg: #ffffff;
    --color-primary: #0056b3;
    --color-primary-light: #e6f0ff;
    --color-border: #e0e0e0;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

/* --- Estilos para el Modo Oscuro --- */
body.dark-mode {
    --color-bg: #1a1a1a;
    --color-text: #e0e0e0;
    --color-card-bg: #2c2c2c;
    --color-primary: #4dabf7;
    --color-primary-light: #2c3e50;
    --color-border: #444;
    --shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

/* --- Reset y Estilos Base --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

body {
    font-family: var(--font-primary);
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
}

.container {
    max-width: 900px;
    margin: 40px auto;
    padding: 20px;
    background-color: var(--color-card-bg);
    border-radius: 12px;
    box-shadow: var(--shadow);
    border: 1px solid var(--color-border);
}

/* --- Header y Contacto --- */
header {
    text-align: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid var(--color-primary);
}

header h1 {
    font-family: var(--font-headings);
    font-size: 2.5em;
    color: var(--color-primary);
    margin-bottom: 10px;
}

.contact-info {
    font-size: 1.1em;
}

.contact-info a {
    color: var(--color-text);
    text-decoration: none;
    font-weight: bold;
    transition: color 0.2s ease;
}

.contact-info a:hover {
    color: var(--color-primary);
}

.contact-info i {
    margin-right: 8px;
    color: var(--color-primary);
}

.contact-info .separator {
    margin: 0 10px;
    color: var(--color-border);
}

/* --- Secciones --- */
.section {
    margin-bottom: 25px;
    padding: 20px;
    background-color: var(--color-bg);
    border-radius: 8px;
    border: 1px solid var(--color-border);
}

.section-title {
    font-family: var(--font-headings);
    font-size: 1.5em;
    color: var(--color-primary);
    margin-bottom: 15px;
    padding-bottom: 5px;
    border-bottom: 1px solid var(--color-primary-light);
}

.section-title i {
    margin-right: 12px;
}

ul {
    list-style: none;
    padding-left: 0;
}

li {
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
}

li::before {
    content: '•';
    color: var(--color-primary);
    font-weight: bold;
    position: absolute;
    left: 0;
    top: 0;
}

/* --- Estructuras de Grid para Habilidades --- */
.tech-stack-grid, .skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.tech-category h3, .skills-grid h3 {
    font-family: var(--font-headings);
    color: var(--color-text);
    margin-bottom: 10px;
    font-size: 1.1em;
}
.tech-category i {
    margin-right: 8px;
}

/* --- Interruptor de Modo Oscuro --- */
.theme-switch-wrapper {
    display: flex;
    align-items: center;
    gap: 10px;
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 100;
    padding: 8px;
    background: var(--color-card-bg);
    border-radius: 20px;
    box-shadow: var(--shadow);
}
.theme-switch {
    display: inline-block;
    height: 24px;
    position: relative;
    width: 48px;
}
.theme-switch input {
    display: none;
}
.slider {
    background-color: #ccc;
    bottom: 0;
    cursor: pointer;
    left: 0;
    position: absolute;
    right: 0;
    top: 0;
    transition: .4s;
}
.slider:before {
    background-color: #fff;
    bottom: 3px;
    content: "";
    height: 18px;
    left: 3px;
    position: absolute;
    transition: .4s;
    width: 18px;
}
input:checked + .slider {
    background-color: var(--color-primary);
}
input:checked + .slider:before {
    transform: translateX(24px);
}
.slider.round {
    border-radius: 24px;
}
.slider.round:before {
    border-radius: 50%;
}