/* Reset and Base Styles */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Paleta temática energia */
    --color-primary: #3bb273; /* Verde energia */
    --color-primary-light: #7ee8fa; /* Azul claro energia */
    --color-primary-dark: #1e6f5c; /* Verde escuro */
    --color-secondary: #2b90d9; /* Azul tecnologia */
    --color-secondary-light: #b2f7ef; /* Azul pastel */
    --color-accent: #ffd166; /* Amarelo destaque */
    --color-accent-light: #fff3cd;
    --color-consumption-low: #3bb273; /* Verde para baixo consumo */
    --color-consumption-high: #ff6b6b; /* Vermelho para alto consumo */
    --color-background: #f4f9f9;
    --color-surface: #ffffff;
    --color-surface-hover: #eaf6f6;
    --color-border: #d0e2e7;
    --color-border-focus: #2b90d9;
    --color-text: #1e293b;
    --color-text-light: #5c7080;
    --color-text-muted: #8da1b9;
    --color-text-inverse: #ffffff;
    --font-family: 'Rubik', 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    
    /* Neutral Colors */
    --color-background: #f6f7fa;        /* Fundo levemente acinzentado/quente */
    --color-surface: #ffffff;
    --color-surface-hover: #f3f5f9;
    --color-border: #e3e7ef;
    --color-border-focus: #cfd8e6;
    
    /* Text Colors */
    --color-text: #26324b;              /* Cinza escuro suave */
    --color-text-light: #6b7a99;
    --color-text-muted: #a0aec0;
    --color-text-inverse: #ffffff;
    
    /* Status Colors */
    --color-success: #5fc9a4;
    --color-success-light: #e6f9f1;
    --color-error: #e57373;
    --color-error-light: #ffeaea;
    --color-warning: #ffd580;
    --color-warning-light: #fff8e1;
    --color-info: #7ec3e6;
    --color-info-light: #eaf6fb;
    
    /* Dark Mode Colors */
    --color-dark-background: #181f2e;
    --color-dark-surface: #232c3e;
    --color-dark-surface-hover: #2e3950;
    --color-dark-border: #3a4661;
    --color-dark-text: #e6eaf3;
    --color-dark-text-light: #bfc8db;
    --color-dark-text-muted: #8a97b5;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    
    /* Spacing */
    --spacing-1: 0.25rem;
    --spacing-2: 0.5rem;
    --spacing-3: 0.75rem;
    --spacing-4: 1rem;
    --spacing-5: 1.25rem;
    --spacing-6: 1.5rem;
    --spacing-8: 2rem;
    --spacing-10: 2.5rem;
    --spacing-12: 3rem;
    --spacing-16: 4rem;
    --spacing-20: 5rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-focus: 0 0 0 3px rgba(37, 99, 235, 0.1);
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Z-index */
    --z-dropdown: 1000;
    --z-sticky: 1020;
    --z-fixed: 1030;
    --z-modal: 1040;
    --z-popover: 1050;
    --z-tooltip: 1060;
    --z-toast: 1070;
}

/* Dark Mode */
@media (prefers-color-scheme: dark) {
    :root {
        --color-background: var(--color-dark-background);
        --color-surface: var(--color-dark-surface);
        --color-surface-hover: var(--color-dark-surface-hover);
        --color-border: var(--color-dark-border);
        --color-text: var(--color-dark-text);
        --color-text-light: var(--color-dark-text-light);
        --color-text-muted: var(--color-dark-text-muted);
    }
}

/* Base Typography */
html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    
    background-color:var(--color-primary-dark);
    
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--color-text);
    background: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-secondary-light) 100%) fixed;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.header__icon {
    width: 60px;
    height: 60px;
    vertical-align: middle;
    display: inline-block;
    object-fit: contain;
    margin-right: 0.25em;
}

/* Skip Link for Accessibility */
.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--color-primary);
    color: var(--color-text-inverse);
    padding: var(--spacing-2) var(--spacing-4);
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 600;
    z-index: var(--z-tooltip);
    transition: var(--transition-fast);
}

.skip-link:focus {
    top: 6px;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-4);
    width: 100%;
}

/* Header */
.header {
    background: linear-gradient(120deg, var(--color-primary) 0%, var(--color-secondary) 100%) !important;
    color: var(--color-text-inverse);
    padding: var(--spacing-12) 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    box-shadow: 0 6px 24px 0 rgba(43, 144, 217, 0.08);
    border-bottom-left-radius: 2.5rem;
    border-bottom-right-radius: 2.5rem;
}

.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: radial-gradient(circle at 20% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
                      radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
    animation: headerFloat 6s ease-in-out infinite;
}

@keyframes headerFloat {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
}

.header__title {
   
    align-items: center;
    gap: 0.25em;
    font-size: var(--font-size-4xl);
    font-weight: 800;
    margin-bottom: var(--spacing-3);
    position: relative;
    z-index: 1;
    line-height: var(--line-height-tight);
}

.header__icon {
    display: inline-block;
    margin-right: var(--spacing-3);
    font-size: 1.2em;
    animation: iconPulse 2s ease-in-out infinite;
}

@keyframes iconPulse {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

.header__subtitle {
    font-size: var(--font-size-lg);
    opacity: 0.95;
    position: relative;
    z-index: 1;
    font-weight: 400;
    max-width: 600px;
    margin: 0 auto;
}

/* Main Content */
.main {
    flex: 1;
    padding: var(--spacing-16) 0;
}

/* Calculator Section */
.calculator {
    background: var(--color-surface);
    border-radius: 2rem;
    box-shadow: 0 8px 32px 0 rgba(59, 178, 115, 0.10), 0 1.5px 6px 0 rgba(43, 144, 217, 0.06);
    border: 2px solid var(--color-border);
    padding: var(--spacing-10);
    margin-bottom: var(--spacing-12);
    transition: var(--transition-normal);
}

.calculator:hover {
    box-shadow: var(--shadow-xl);
}

.calculator__title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-8);
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
}

.calculator__icon {
    font-size: 1.2em;
}

/* Form Styles */
.form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-6);
}

.form__description {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-4);
}

.form__row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-6);
}

.form__group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-2);
}

.form__label {
    font-weight: 600;
    color: var(--color-text);
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    font-size: var(--font-size-sm);
}

.form__required {
    color: var(--color-error);
    font-weight: 700;
}

.form__label-icon {
    font-size: 1em;
}

.form__input-group {
    display: flex;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: var(--transition-fast);
    background: var(--color-surface);
    position: relative;
}

.form__input-group:focus-within {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-focus);
}

.form__input {
    flex: 1;
    padding: var(--spacing-4);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-base);
    transition: var(--transition-fast);
    background: var(--color-surface);
    color: var(--color-text);
    font-family: inherit;
}

.form__input:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: var(--shadow-focus);
}

.form__input:invalid:not(:placeholder-shown) {
    border-color: var(--color-error);
}

.form__input.error {
    border-color: var(--color-error);
    background-color: var(--color-error-light);
}

.form__input-group .form__input {
    border: none;
    border-radius: 0;
    box-shadow: none;
}

.form__select {
    padding: var(--spacing-4);
    border: none;
    background: var(--color-primary);
    color: var(--color-text-inverse);
    font-size: var(--font-size-base);
    cursor: pointer;
    min-width: 80px;
    font-weight: 600;
    transition: var(--transition-fast);
}

.form__select:hover {
    background: var(--color-primary-dark);
}

.form__help {
    color: var(--color-text-muted);
    font-size: var(--font-size-xs);
    line-height: var(--line-height-normal);
}

.form__error {
    color: var(--color-error);
    font-size: var(--font-size-sm);
    font-weight: 500;
    min-height: 1.2em;
    display: block;
    margin-top: var(--spacing-1);
}

/* Button Styles */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    padding: var(--spacing-4) var(--spacing-6);
    border: none;
    border-radius: 2rem;
    font-size: 1.1rem;
    font-weight: 700;
    letter-spacing: 0.02em;
    box-shadow: 0 2px 8px 0 rgba(43, 144, 217, 0.10);
    background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    color: var(--color-text-inverse);
    transition: box-shadow 0.2s, transform 0.2s, background 0.2s;
    position: relative;
    overflow: hidden;
    white-space: nowrap;
    min-height: 44px; /* Accessibility: minimum touch target */
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.btn:hover:not(:disabled)::before {
    left: 100%;
}

.btn--primary {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%) !important;
    color: var(--color-text-inverse);
    box-shadow: var(--shadow-md);
}

.btn--primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn--primary:active {
    transform: translateY(0);
}

.btn--secondary {
    background: var(--color-surface);
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
    box-shadow: var(--shadow-sm);
}

.btn--secondary:hover:not(:disabled) {
    background: var(--color-primary);
    color: var(--color-text-inverse);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn--danger {
    background: linear-gradient(135deg, var(--color-error) 0%, #f7b2b2 100%) !important;
    color: var(--color-text-inverse);
    box-shadow: var(--shadow-md);
}

.btn--danger:hover:not(:disabled) {
    background: linear-gradient(135deg, #b91c1c 0%, var(--color-error) 100%);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn--small {
    padding: var(--spacing-2) var(--spacing-4);
    font-size: var(--font-size-sm);
    min-height: 36px;
}

.btn__icon {
    font-size: 1.5em;
}

.btn__loading {
    display: none;
    width: 16px;
    height: 16px;
    border: 2px solid transparent;
    border-top: 2px solid currentColor;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.btn.loading .btn__text {
    opacity: 0;
}

.btn.loading .btn__loading {
    display: block;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Results Section */
.results {
    margin-top: var(--spacing-10);
    padding-top: var(--spacing-10);
    border-top: 2px solid var(--color-border);
    animation: fadeInUp 0.5s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.results__title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-8);
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
}

.results__icon {
    font-size: 1.2em;
}

/* Device List */
.device-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-4);
    margin-bottom: var(--spacing-10);
}

.device-item {
    background: var(--color-surface-hover);
    border: 2px solid var(--color-border);
    border-radius: 1.5rem;
    box-shadow: 0 2px 8px 0 rgba(43, 144, 217, 0.06);
    padding: var(--spacing-6);
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: var(--spacing-4);
    align-items: center;
    transition: box-shadow 0.3s, border 0.3s;
    position: relative;
    overflow: hidden;
}

.device-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 6px;
    background: linear-gradient(180deg, var(--color-primary) 0%, var(--color-secondary) 100%) !important;
    border-radius: 6px;
    transition: background 0.3s;
}

.device-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.device-item:hover::before {
    transform: scaleY(1);
}

.device-info h3 {
    color: var(--color-primary);
    margin-bottom: var(--spacing-2);
    font-size: var(--font-size-lg);
    font-weight: 600;
}

.device-info p {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-1);
    line-height: var(--line-height-normal);
}

.device-results {
    text-align: right;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-1);
}

.device-consumption {
    color: var(--color-secondary);
    font-weight: 600;
    font-size: var(--font-size-base);
}

.device-cost {
    color: var(--color-primary);
    font-weight: 700;
    font-size: var(--font-size-lg);
}

.device-remove {
    background: var(--color-error);
    color: var(--color-text-inverse);
    border: none;
    border-radius: var(--radius-full);
    width: 40px;
    height: 40px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-fast);
    font-size: var(--font-size-lg);
    font-weight: 700;
}

.device-remove:hover {
    background: #b91c1c;
    transform: scale(1.1);
}

.device-remove:active {
    transform: scale(0.95);
}

.device-item[data-consumption='low'] .device-consumption {
    color: var(--color-consumption-low);
    font-weight: 700;
}
.device-item[data-consumption='high'] .device-consumption {
    color: var(--color-consumption-high);
    font-weight: 700;
}

/* Summary */
.summary {
    background: linear-gradient(120deg, var(--color-primary-light) 0%, var(--color-secondary-light) 100%) !important;
    color: var(--color-text);
    border-radius: 2rem;
    box-shadow: 0 4px 16px 0 rgba(59, 178, 115, 0.10);
    padding: var(--spacing-8);
    margin-bottom: var(--spacing-10);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-8);
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
}

.summary::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 30% 70%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
}

.summary__item {
    display: flex;
    align-items: center;
    gap: var(--spacing-4);
    position: relative;
    z-index: 1;
}

.summary__icon {
    font-size: var(--font-size-3xl);
    opacity: 0.9;
}

.summary__content {
    display: flex;
    flex-direction: column;
}

.summary__label {
    font-size: var(--font-size-sm);
    opacity: 0.9;
    margin-bottom: var(--spacing-1);
    font-weight: 500;
}

.summary__value {
    font-size: var(--font-size-2xl);
    font-weight: 800;
    line-height: var(--line-height-tight);
}

/* Actions */
.actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-4);
    justify-content: center;
}

/* History Section */
.history {
    background: var(--color-surface);
    border-radius: 2rem;
    box-shadow: 0 8px 32px 0 rgba(59, 178, 115, 0.10), 0 1.5px 6px 0 rgba(43, 144, 217, 0.06);
    border: 2px solid var(--color-border);
    padding: var(--spacing-10);
    margin-bottom: var(--spacing-12);
    animation: fadeInUp 0.5s ease-out 0.2s both;
}

.history__title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-8);
    display: flex;
    align-items: center;
    gap: var(--spacing-3);
}

.history__icon {
    font-size: 1.2em;
}

.history__list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-4);
    margin-bottom: var(--spacing-8);
}

.history-item {
    background: var(--color-surface-hover);
    border: 2px solid var(--color-border);
    border-radius: 1.5rem;
    box-shadow: 0 2px 8px 0 rgba(43, 144, 217, 0.06);
    padding: var(--spacing-6);
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: var(--spacing-4);
    align-items: center;
    transition: var(--transition-normal);
}

.history-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.history-info h4 {
    color: var(--color-primary);
    margin-bottom: var(--spacing-2);
    font-weight: 600;
}

.history-info p {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    line-height: var(--line-height-normal);
}

.history-results {
    text-align: right;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-1);
}

.history-load {
    background: var(--color-accent);
    color: var(--color-text);
    border: none;
    border-radius: var(--radius-lg);
    padding: var(--spacing-3) var(--spacing-4);
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition-fast);
    font-size: var(--font-size-sm);
}

.history-load:hover {
    background: var(--color-accent-light);
    transform: scale(1.05);
}

/* FAQ Section */
.faq {
    background: var(--color-surface);
    border-radius: 2rem;
    box-shadow: 0 8px 32px 0 rgba(59, 178, 115, 0.10), 0 1.5px 6px 0 rgba(43, 144, 217, 0.06);
    border: 2px solid var(--color-border);
    padding: var(--spacing-10);
    margin-bottom: var(--spacing-12);
    animation: fadeInUp 0.5s ease-out 0.4s both;
}

.faq__title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-8);
    text-align: center;
}

.faq__list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-4);
}

.faq__item {
    border: 1px solid var(--color-border);
    border-radius: var(--radius-xl);
    overflow: hidden;
    transition: var(--transition-normal);
}

.faq__item:hover {
    box-shadow: var(--shadow-md);
}

.faq__question {
    background: var(--color-surface-hover);
    padding: var(--spacing-6);
    cursor: pointer;
    font-weight: 600;
    color: var(--color-primary);
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: var(--transition-fast);
    font-size: var(--font-size-base);
}

.faq__question:hover {
    background: var(--color-border);
}

.faq__question::after {
    content: '+';
    font-size: var(--font-size-xl);
    font-weight: 700;
    transition: var(--transition-fast);
    color: var(--color-primary);
}

.faq__item[open] .faq__question::after {
    transform: rotate(45deg);
}

.faq__answer {
    padding: var(--spacing-6);
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
}

.faq__answer p {
    color: var(--color-text);
    line-height: var(--line-height-relaxed);
}

/* Footer */
.footer {
    background: var(--color-primary);
    color: var(--color-text-inverse);
    text-align: center;
    padding: var(--spacing-8) 0;
    margin-top: auto;
}

.footer__text {
    font-size: var(--font-size-sm);
    opacity: 0.95;
    font-weight: 500;
}

/* Toast Notifications */
.toast {
    position: fixed;
    top: var(--spacing-6);
    right: var(--spacing-6);
    background: var(--color-success);
    color: var(--color-text-inverse);
    padding: var(--spacing-4) var(--spacing-6);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    z-index: var(--z-toast);
    transform: translateX(400px);
    transition: var(--transition-normal);
    font-weight: 600;
    min-width: 280px;
    max-width: 400px;
}

.toast.show {
    transform: translateX(0);
}

.toast.error {
    background: var(--color-error);
}

.toast.warning {
    background: var(--color-warning);
}

.toast.info {
    background: var(--color-info);
}

/* Loading Overlay */
.loading {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(4px);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: var(--z-modal);
}

.loading__spinner {
    width: 60px;
    height: 60px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid var(--color-text-inverse);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: var(--spacing-4);
}

.loading__text {
    color: var(--color-text-inverse);
    font-size: var(--font-size-lg);
    font-weight: 600;
}

/* Install PWA Button */
.install-btn {
    position: fixed;
    bottom: var(--spacing-6);
    right: var(--spacing-6);
    background: var(--color-primary);
    color: var(--color-text-inverse);
    border: none;
    border-radius: var(--radius-full);
    padding: var(--spacing-4) var(--spacing-6);
    box-shadow: var(--shadow-lg);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: var(--spacing-2);
    font-weight: 600;
    transition: var(--transition-fast);
    z-index: var(--z-fixed);
    animation: slideInUp 0.5s ease-out;
}

.install-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

@keyframes slideInUp {
    from {
        transform: translateY(100px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.install-btn__icon {
    font-size: 1.2em;
}

/* Screen Reader Only */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Focus Styles for Accessibility */
*:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

.btn:focus-visible,
.form__input:focus-visible,
.form__select:focus-visible {
    box-shadow: var(--shadow-focus);
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-4);
    }
    
    .header {
        padding: var(--spacing-8) 0;
    }
    
    .header__title {
        font-size: var(--font-size-3xl);
    }
    
    .header__subtitle {
        font-size: var(--font-size-base);
    }
    
    .main {
        padding: var(--spacing-8) 0;
    }
    
    .calculator,
    .history,
    .faq {
        padding: var(--spacing-6);
    }
    
    .form__row {
        grid-template-columns: 1fr;
        gap: var(--spacing-4);
    }
    
    .summary {
        grid-template-columns: 1fr;
        gap: var(--spacing-6);
        padding: var(--spacing-6);
    }
    
    .summary__value {
        font-size: var(--font-size-xl);
    }
    
    .device-item {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--spacing-3);
    }
    
    .device-results {
        text-align: center;
    }
    
    .history-item {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--spacing-3);
    }
    
    .history-results {
        text-align: center;
    }
    
    .actions {
        flex-direction: column;
        gap: var(--spacing-3);
    }
    
    .toast {
        right: var(--spacing-4);
        left: var(--spacing-4);
        transform: translateY(-100px);
        min-width: auto;
    }
    
    .toast.show {
        transform: translateY(0);
    }
    
    .install-btn {
        bottom: var(--spacing-4);
        right: var(--spacing-4);
    }
}

@media (max-width: 480px) {
    .header__title {
        font-size: var(--font-size-2xl);
    }
    
    .calculator__title,
    .results__title,
    .history__title,
    .faq__title {
        font-size: var(--font-size-xl);
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .summary__item {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-2);
    }
    
    .summary__icon {
        font-size: var(--font-size-2xl);
    }
}

/* Print Styles */
@media print {
    .header,
    .footer,
    .actions,
    .btn,
    .install-btn,
    .toast,
    .loading {
        display: none !important;
    }
    
    .calculator,
    .results,
    .history {
        box-shadow: none;
        border: 1px solid #000;
        break-inside: avoid;
    }
    
    body {
        background: white;
        color: black;
        font-size: 12pt;
    }
    
    .summary {
        background: #f5f5f5 !important;
        color: black !important;
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --color-primary: #000080;
        --color-secondary: #006400;
        --color-accent: #ff6600;
        --color-background: #ffffff;
        --color-surface: #ffffff;
        --color-text: #000000;
        --color-border: #000000;
        --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
        --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
    }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* Large Screens */
@media (min-width: 1200px) {
    .container {
        padding: 0 var(--spacing-8);
    }
    
    .form__row {
        grid-template-columns: 1fr 1fr;
        gap: var(--spacing-8);
    }
    
    .calculator,
    .history,
    .faq {
        padding: var(--spacing-12);
    }
}

/* Hover Effects (only for devices that support hover) */
@media (hover: hover) {
    .device-item:hover,
    .history-item:hover,
    .faq__item:hover {
        transform: translateY(-2px);
    }
    
    .btn:hover:not(:disabled) {
        transform: translateY(-2px);
    }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-border);
    border-radius: var(--radius-md);
}

::-webkit-scrollbar-thumb {
    background: var(--color-primary);
    border-radius: var(--radius-md);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-primary-dark);
}

/* Selection */
::selection {
    background: var(--color-primary);
    color: var(--color-text-inverse);
}

/* Tooltip custom */
.form__label[title] {
    position: relative;
    cursor: help;
}
.form__label[title]:hover::after {
    content: attr(title);
    position: absolute;
    left: 0;
    top: 120%;
    background: var(--color-secondary);
    color: var(--color-text-inverse);
    padding: 0.4em 0.8em;
    border-radius: 0.5em;
    font-size: 0.95em;
    white-space: nowrap;
    z-index: 10;
    box-shadow: 0 2px 8px 0 rgba(43, 144, 217, 0.10);
}

/* Pequenos ícones de energia nos títulos */
.calculator__title::before, .results__title::before, .history__title::before, .faq__title::before {
    content: '⚡ ';
    font-size: 1.2em;
    margin-right: 0.3em;
    color: var(--color-primary);
}