/* ============================================
   BMI CALCULATOR - CON SELECTORES DE UNIDADES
   ============================================ */

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

/* VARIABLES GLOBALES */
:root {
    --bg-light: #F0F4FA;
    --bg-dark: #121212;
    --card-light: #FFFFFF;
    --card-dark: #1E1E1E;
    --accent: #667eea;
    --accent-dark: #764ba2;
    --text-light: #333333;
    --text-dark: #EAEAEA;
    --border-light: #e0e0e0;
    --border-dark: #333333;
}

body {
    font-family: 'Inter', sans-serif;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    line-height: 1.5;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* MODO CLARO (por defecto) */
body.light-mode {
    background: var(--bg-light);
    color: var(--text-light);
}

body.light-mode .container {
    background: var(--card-light);
    border: 2px solid var(--accent);
    box-shadow: 0 20px 35px -10px rgba(102, 126, 234, 0.2);
}

body.light-mode .calculator-card {
    background: #f8f9fa;
    border: 1px solid var(--border-light);
}

body.light-mode input {
    border: 2px solid var(--border-light);
    color: var(--text-light);
    background: white;
}

body.light-mode .unit-select {
    border: 2px solid var(--border-light);
    background: white;
    color: var(--text-light);
}

body.light-mode .info-section {
    background: #e8f4fd;
}

/* MODO OSCURO - CORREGIDO (colores vibrantes) */
body.dark-mode {
    background: var(--bg-dark);
    color: var(--text-dark);
}

body.dark-mode .container {
    background: var(--card-dark);
    border: 2px solid #2A2A2A;
    box-shadow: 0 20px 35px -10px rgba(0, 0, 0, 0.5);
}

body.dark-mode .calculator-card {
    background: #2A2A2A;
    border: 1px solid #3A3A3A;
}

body.dark-mode input {
    background: #1A1A1A;
    border: 2px solid #3A3A3A;
    color: var(--text-dark);
}

body.dark-mode .unit-select {
    background: #1A1A1A;
    border: 2px solid #3A3A3A;
    color: var(--text-dark);
}

body.dark-mode input::placeholder {
    color: #888;
}

body.dark-mode .info-section {
    background: #2A2A2A;
}

body.dark-mode .info-section h3 {
    color: var(--text-dark);
}

body.dark-mode footer {
    background: #0A0A0A;
}

/* ===== RESULTADO EN MODO OSCURO - CORREGIDO ===== */
body.dark-mode .result-card {
    background: #2A2A2A;
    border: 2px solid #8A9EFF;  /* Borde azul más brillante */
}

body.dark-mode .bmi-number {
    color: #8A9EFF;  /* Azul claro vibrante */
    font-weight: 800;
    text-shadow: 0 2px 5px rgba(138, 158, 255, 0.2);
}

body.dark-mode .bmi-category {
    font-size: 1.5rem;
    margin: 12px 0;
    font-weight: 700;
}

/* COLORES BRILLANTES PARA CATEGORÍAS EN MODO OSCURO */
body.dark-mode .bmi-category.underweight { 
    color: #FFB347;  /* Naranja brillante */
}

body.dark-mode .bmi-category.normal { 
    color: #6FCF97;  /* Verde brillante */
}

body.dark-mode .bmi-category.overweight { 
    color: #FF8A5C;  /* Naranja-rojo brillante */
}

body.dark-mode .bmi-category.obese { 
    color: #FF6B6B;  /* Rojo brillante */
}

body.dark-mode .bmi-detail {
    color: #CCCCCC;  /* Gris claro visible */
    line-height: 1.6;
    font-size: 1rem;
}

body.dark-mode .ad-space {
    background: #1E1E1E;
    border: 1px dashed #8A9EFF;
}

body.dark-mode .ad-space a {
    color: #8A9EFF;
}

/* MODO CLARO (se mantiene igual) */
body.light-mode .bmi-number {
    color: #667eea;
}

/* ELEMENTOS COMUNES */
.page-wrapper {
    width: 100%;
    max-width: 750px;
    display: flex;
    justify-content: center;
}

.container {
    border-radius: 28px;
    width: 100%;
    max-width: 650px;
    overflow: hidden;
    transition: all 0.3s ease;
}

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 30px 30px 20px;
    text-align: center;
}

.header-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.language-selector {
    display: flex;
    gap: 8px;
}

.lang-btn {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 6px 14px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    transition: all 0.2s;
}

.lang-btn.active {
    background: white;
    color: #667eea;
    border-color: white;
}

.dark-mode-btn {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 6px 14px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    transition: all 0.2s;
}

.dark-mode-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

h1 {
    font-size: 2.4rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: white;
    letter-spacing: -0.5px;
}

.subtitle {
    font-size: 1rem;
    opacity: 0.95;
    color: white;
}

main {
    padding: 30px;
}

.calculator-card {
    border-radius: 20px;
    padding: 25px;
    margin-bottom: 25px;
    box-shadow: 0 10px 20px -8px rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s ease;
}

.input-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    font-size: 0.95rem;
}

/* INPUT CON SELECTOR */
.input-with-select {
    display: flex;
    align-items: center;
    gap: 10px;
}

.input-with-select input {
    flex: 2;
    width: 100%;
    padding: 14px 16px;
    border-radius: 12px;
    font-size: 1rem;
    transition: all 0.2s;
    font-family: 'Inter', sans-serif;
}

.input-with-select input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
}

/* SELECTOR DE UNIDADES */
.unit-select {
    flex: 1;
    padding: 14px 16px;
    border-radius: 12px;
    font-size: 1rem;
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%23667eea' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'><polyline points='6 9 12 15 18 9'/></svg>");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 14px;
    transition: all 0.2s;
    font-family: 'Inter', sans-serif;
}

.unit-select:focus {
    outline: none;
    border-color: #667eea;
}

.calculate-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 16px;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    width: 100%;
    transition: all 0.2s;
    margin-top: 10px;
    box-shadow: 0 8px 16px -6px rgba(102, 126, 234, 0.3);
}

.calculate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 20px -8px rgba(102, 126, 234, 0.4);
}

.result-card {
    background: #f8f9fa;
    border-radius: 20px;
    padding: 25px;
    margin-bottom: 25px;
    text-align: center;
    border: 2px solid #667eea;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.hidden {
    display: none;
}

.bmi-number {
    color: #667eea;
    font-weight: 800;
    font-size: 3rem;
    line-height: 1.2;
}

.bmi-category {
    font-size: 1.5rem;
    margin: 12px 0;
    font-weight: 700;
}

.bmi-detail {
    line-height: 1.6;
    font-size: 1rem;
    max-width: 450px;
    margin: 0 auto;
}

/* COLORES PARA CATEGORÍAS EN RESULTADO */
.bmi-category.underweight { color: #b45309; }
.bmi-category.normal { color: #0b5e42; }
.bmi-category.overweight { color: #c2410c; }
.bmi-category.obese { color: #b91c1c; }

.ad-space {
    margin-top: 20px;
    padding: 15px;
    background: white;
    border-radius: 12px;
    border: 1px dashed #667eea;
}

.ad-space a {
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
}

.info-section {
    border-radius: 15px;
    padding: 20px;
    transition: background-color 0.3s ease;
}

.info-section h3 {
    margin-bottom: 15px;
    text-align: center;
    font-size: 1.2rem;
    font-weight: 600;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.category-item {
    padding: 12px;
    border-radius: 10px;
    text-align: center;
    color: white;
    font-weight: 500;
    box-shadow: 0 4px 6px -2px rgba(0, 0, 0, 0.2);
}

.underweight { background: #ffc107; color: #333; }
.normal { background: #28a745; }
.overweight { background: #fd7e14; }
.obese { background: #dc3545; }

.category-item .range {
    display: block;
    font-size: 0.85rem;
    opacity: 0.9;
    margin-bottom: 5px;
}

.category-item .label {
    display: block;
    font-weight: 600;
    font-size: 1.1rem;
}

footer {
    padding: 15px;
    text-align: center;
    font-size: 0.9rem;
    transition: background-color 0.3s ease;
}

footer p {
    opacity: 0.9;
}

/* RESPONSIVE */
@media (max-width: 480px) {
    h1 { font-size: 2rem; }
    
    .input-with-select {
        flex-direction: column;
        gap: 8px;
    }
    
    .input-with-select input,
    .unit-select {
        width: 100%;
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
    }
    
    .bmi-number {
        font-size: 2.5rem;
    }
    
    .bmi-category {
        font-size: 1.3rem;
    }
}