:root {
    --primary: #667eea;
    --primary-dark: #764ba2;
    --secondary: #f093fb;
    --success: #4ade80;
    --warning: #fbbf24;
    --danger: #ef4444;
    --info: #3b82f6;
    
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    
    --text-primary: #333333;
    --text-secondary: #6c757d;
    --text-light: #adb5bd;
    
    --border-color: #e9ecef;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.3);
    
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

[data-theme="dark"] {
    --bg-primary: #1a1a2e;
    --bg-secondary: #16213e;
    --bg-tertiary: #0f3460;
    
    --text-primary: #eaeaea;
    --text-secondary: #a8b2d1;
    --text-light: #8892b0;
    
    --border-color: #2d3561;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.5);
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    position: relative;
    overflow-x: hidden;
    transition: background 0.5s ease;
}

/* Particules Canvas */
#particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

/* Theme Toggle */
.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: var(--bg-primary);
    border: 3px solid var(--primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    z-index: 1001;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-md);
}

.theme-toggle:hover {
    transform: scale(1.1) rotate(15deg);
    box-shadow: var(--shadow-lg);
}

.theme-toggle .moon-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .sun-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .moon-icon {
    display: block;
}

/* Back Button */
.back-button {
    position: fixed;
    top: 20px;
    left: 20px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    padding: 12px 24px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: bold;
    z-index: 1000;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
}

.back-button:hover {
    transform: scale(1.05) translateX(-5px);
    box-shadow: var(--shadow-lg);
}

/* Container */
.container {
    background: var(--bg-primary);
    border-radius: 20px;
    box-shadow: var(--shadow-lg);
    width: 100%;
    max-width: 600px;
    overflow: hidden;
    position: relative;
    z-index: 1;
    transition: background var(--transition-slow);
}

/* Header animé */
.header-animated {
    padding: 30px 30px 20px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.header-animated::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: pulse 3s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 0.5; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

.glitch {
    font-size: 32px;
    font-weight: 900;
    color: white;
    text-transform: uppercase;
    position: relative;
    letter-spacing: 2px;
    animation: glitch-anim 5s infinite;
}

@keyframes glitch-anim {
    0%, 90%, 100% { transform: translate(0); }
    92% { transform: translate(-2px, 2px); }
    94% { transform: translate(2px, -2px); }
    96% { transform: translate(-2px, -2px); }
    98% { transform: translate(2px, 2px); }
}

.subtitle {
    color: rgba(255, 255, 255, 0.9);
    font-size: 14px;
    margin-top: 8px;
    font-weight: 300;
    letter-spacing: 1px;
}

/* Tabs */
.tabs {
    display: flex;
    background: var(--bg-secondary);
    border-bottom: 2px solid var(--border-color);
    position: relative;
    overflow-x: auto;
    scrollbar-width: none;
}

.tabs::-webkit-scrollbar {
    display: none;
}

.tab {
    flex: 1;
    min-width: 100px;
    padding: 16px 12px;
    text-align: center;
    cursor: pointer;
    background: transparent;
    border: none;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    transition: all var(--transition-normal);
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.tab-icon {
    font-size: 20px;
    transition: transform var(--transition-normal);
}

.tab-text {
    font-size: 12px;
}

.tab:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.tab:hover .tab-icon {
    transform: scale(1.2) rotate(5deg);
}

.tab.active {
    color: var(--primary);
    background: var(--bg-primary);
}

.tab.active .tab-icon {
    animation: bounce 0.5s ease;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.tab.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--primary-dark));
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from { transform: scaleX(0); }
    to { transform: scaleX(1); }
}

/* Tooltips */
.tab[data-tooltip]:hover::before {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(-10px);
    background: var(--text-primary);
    color: var(--bg-primary);
    padding: 8px 12px;
    border-radius: 8px;
    font-size: 11px;
    white-space: nowrap;
    z-index: 10;
    animation: fadeInUp 0.3s ease;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateX(-50%) translateY(0); }
    to { opacity: 1; transform: translateX(-50%) translateY(-10px); }
}

/* Content */
.content {
    padding: 30px;
    min-height: 400px;
}

.calculator {
    display: none;
}

.calculator.active {
    display: block;
    animation: fadeInScale 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes fadeInScale {
    from {
        opacity: 0;
        transform: scale(0.95) translateY(20px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

h2 {
    color: var(--text-primary);
    margin-bottom: 25px;
    font-size: 24px;
    text-align: center;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Floating Labels */
.input-group {
    margin-bottom: 25px;
    position: relative;
}

.floating-label {
    position: relative;
}

.floating-label input {
    width: 100%;
    padding: 16px 45px 16px 15px;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 16px;
    transition: all var(--transition-normal);
    background: var(--bg-primary);
    color: var(--text-primary);
}

.floating-label label {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    font-size: 16px;
    font-weight: 500;
    pointer-events: none;
    transition: all var(--transition-normal);
    background: var(--bg-primary);
    padding: 0 5px;
}

.floating-label input:focus,
.floating-label input:not(:placeholder-shown) {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.floating-label input:focus + label,
.floating-label input:not(:placeholder-shown) + label {
    top: 0;
    font-size: 12px;
    color: var(--primary);
    font-weight: 600;
}

.input-icon {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 20px;
    pointer-events: none;
    transition: transform var(--transition-normal);
}

.floating-label input:focus ~ .input-icon {
    transform: translateY(-50%) scale(1.2);
}

label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 14px;
}

input,
select {
    width: 100%;
    padding: 14px 15px;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 16px;
    transition: all var(--transition-normal);
    background: var(--bg-primary);
    color: var(--text-primary);
}

input:focus,
select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* Buttons */
.btn-primary,
.btn-secondary {
    width: 100%;
    padding: 16px;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    box-shadow: var(--shadow-sm);
    margin-top: 10px;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}

.btn-primary:active {
    transform: translateY(-1px);
}

.btn-secondary {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    margin-top: 15px;
}

.btn-secondary:hover {
    background: var(--bg-tertiary);
    border-color: var(--primary);
}

.btn-icon {
    transition: transform var(--transition-fast);
}

.btn-primary:hover .btn-icon {
    transform: translateX(4px);
}

/* Ripple Effect */
[data-ripple] {
    position: relative;
    overflow: hidden;
}

[data-ripple]::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

[data-ripple]:active::after {
    width: 300px;
    height: 300px;
}

/* Result Container */
.result {
    margin-top: 30px;
    padding: 25px;
    background: var(--bg-secondary);
    border-radius: 16px;
    display: none;
    border: 2px solid var(--border-color);
    transition: all var(--transition-normal);
}

.result.show {
    display: block;
    animation: resultAppear 0.6s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes resultAppear {
    0% {
        opacity: 0;
        transform: scale(0.8) rotateX(-90deg);
    }
    100% {
        opacity: 1;
        transform: scale(1) rotateX(0deg);
    }
}

.result-main {
    text-align: center;
    margin: 20px 0;
}

.result-value {
    font-size: 48px;
    font-weight: 900;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 8px;
    line-height: 1;
}

.result-label {
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Tip Options */
.tip-options {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
    margin-top: 10px;
}

.tip-btn {
    padding: 16px 8px;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    cursor: pointer;
    font-weight: 600;
    color: var(--text-primary);
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    position: relative;
}

.tip-percent {
    font-size: 16px;
    font-weight: 700;
}

.tip-emoji {
    font-size: 20px;
    filter: grayscale(1);
    transition: filter var(--transition-normal);
}

.tip-btn:hover {
    background: var(--bg-tertiary);
    transform: translateY(-3px);
    box-shadow: var(--shadow-sm);
}

.tip-btn:hover .tip-emoji {
    filter: grayscale(0);
    animation: wiggle 0.5s ease;
}

@keyframes wiggle {
    0%, 100% { transform: rotate(0deg); }
    25% { transform: rotate(-10deg); }
    75% { transform: rotate(10deg); }
}

.tip-btn.selected {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    border-color: var(--primary);
    transform: scale(1.05);
}

.tip-btn.selected .tip-emoji {
    filter: grayscale(0);
    animation: bounce 0.5s ease;
}

/* Donut Chart */
.chart-container {
    display: flex;
    justify-content: center;
    margin: 20px 0;
}

.donut-chart {
    width: 200px;
    height: 200px;
    transform: rotate(-90deg);
}

.donut-segment {
    fill: none;
    stroke-width: 20;
}

.donut-base {
    stroke: var(--bg-tertiary);
}

.donut-tip {
    stroke: var(--primary);
    stroke-dasharray: 502;
    stroke-dashoffset: 502;
    transition: stroke-dashoffset 1s ease;
    stroke-linecap: round;
}

.donut-text {
    transform: rotate(90deg);
    transform-origin: center;
    fill: var(--text-primary);
}

.donut-value {
    font-size: 32px;
    font-weight: 900;
}

.donut-label {
    font-size: 12px;
    fill: var(--text-secondary);
}

/* Breakdown */
.breakdown {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 2px dashed var(--border-color);
}

.breakdown-item {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
    padding: 12px;
    background: var(--bg-primary);
    border-radius: 10px;
    transition: all var(--transition-fast);
}

.breakdown-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-sm);
}

.breakdown-icon {
    font-size: 20px;
}

.breakdown-item span:nth-child(2) {
    flex: 1;
    color: var(--text-secondary);
    font-size: 14px;
}

.breakdown-item strong {
    color: var(--text-primary);
    font-weight: 700;
}

/* IMC Gauge */
.imc-gauge-container {
    position: relative;
    margin: 30px 0;
}

.imc-gauge {
    width: 100%;
    max-width: 320px;
    height: 150px;
    margin: 0 auto;
    display: block;
}

.gauge-segment {
    stroke-linecap: round;
}

.gauge-underweight {
    stroke: #3b82f6;
}

.gauge-normal {
    stroke: #4ade80;
}

.gauge-overweight {
    stroke: #fbbf24;
}

.gauge-obese {
    stroke: #ef4444;
}

#imc-needle {
    transition: transform 1.2s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

.gauge-labels {
    display: flex;
    justify-content: space-between;
    padding: 0 10px;
    margin-top: -15px;
    position: relative;
}

.gauge-label {
    font-size: 12px;
    color: var(--text-secondary);
    font-weight: 700;
    position: absolute;
}

.imc-category {
    margin-top: 20px;
    padding: 16px;
    border-radius: 12px;
    font-weight: 600;
    text-align: center;
    font-size: 16px;
    animation: slideIn 0.5s ease;
}

.imc-underweight {
    background: rgba(59, 130, 246, 0.15);
    color: #3b82f6;
    border: 2px solid rgba(59, 130, 246, 0.3);
}

.imc-normal {
    background: rgba(74, 222, 128, 0.15);
    color: #22c55e;
    border: 2px solid rgba(74, 222, 128, 0.3);
}

.imc-overweight {
    background: rgba(251, 191, 36, 0.15);
    color: #f59e0b;
    border: 2px solid rgba(251, 191, 36, 0.3);
}

.imc-obese {
    background: rgba(239, 68, 68, 0.15);
    color: #ef4444;
    border: 2px solid rgba(239, 68, 68, 0.3);
}

.imc-info {
    margin-top: 15px;
    padding: 15px;
    background: var(--bg-primary);
    border-radius: 10px;
    border-left: 4px solid var(--primary);
}

.imc-info p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.6;
}

/* Conversion */
.conversion-row {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 15px;
    align-items: end;
    margin-bottom: 25px;
}

.swap-btn {
    padding: 14px;
    width: 50px;
    height: 50px;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: 50%;
    cursor: pointer;
    font-size: 20px;
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    justify-content: center;
    align-self: center;
    margin-top: 28px;
}

.swap-btn:hover {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    border-color: var(--primary);
    transform: rotate(180deg) scale(1.1);
}

.conversion-animation {
    background: var(--bg-primary);
    padding: 20px;
    border-radius: 12px;
    margin-bottom: 20px;
}

.conversion-flow {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
}

.flow-arrow {
    color: var(--primary);
    font-size: 24px;
    animation: pulse 2s ease-in-out infinite;
}

/* History */
.history-controls {
    margin-bottom: 20px;
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.history-item {
    background: var(--bg-secondary);
    padding: 20px;
    border-radius: 12px;
    border: 2px solid var(--border-color);
    transition: all var(--transition-normal);
    animation: slideIn 0.3s ease;
}

.history-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-sm);
    border-color: var(--primary);
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.history-type {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.history-date {
    font-size: 12px;
    color: var(--text-secondary);
}

.history-details {
    color: var(--text-primary);
    font-size: 14px;
    line-height: 1.6;
}

.history-delete {
    margin-top: 12px;
    padding: 8px 16px;
    background: transparent;
    border: 1px solid var(--danger);
    color: var(--danger);
    border-radius: 8px;
    font-size: 12px;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.history-delete:hover {
    background: var(--danger);
    color: white;
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.empty-icon {
    font-size: 64px;
    margin-bottom: 20px;
    opacity: 0.5;
}

.empty-state p {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
}

.empty-state small {
    font-size: 14px;
}

/* Footer */
.footer {
    padding: 20px;
    text-align: center;
    border-top: 2px solid var(--border-color);
    background: var(--bg-secondary);
}

.footer p {
    color: var(--text-secondary);
    font-size: 13px;
    font-weight: 500;
}

/* Toast Notifications */
#toast-container {
    position: fixed;
    top: 100px;
    right: 20px;
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast {
    min-width: 300px;
    padding: 16px 20px;
    background: var(--bg-primary);
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    border-left: 4px solid var(--primary);
    display: flex;
    align-items: center;
    gap: 12px;
    animation: toastIn 0.3s ease;
}

@keyframes toastIn {
    from {
        opacity: 0;
        transform: translateX(100%);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.toast.success {
    border-left-color: var(--success);
}

.toast.error {
    border-left-color: var(--danger);
}

.toast-icon {
    font-size: 24px;
}

.toast-message {
    flex: 1;
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 500;
}

/* Responsive */
@media (max-width: 768px) {
    body {
        padding: 0;
    }

    .container {
        border-radius: 0;
        max-width: 100%;
    }

    .back-button,
    .theme-toggle {
        width: 50px;
        height: 50px;
        padding: 8px 16px;
        font-size: 14px;
    }

    .header-animated {
        padding: 20px 15px 15px;
    }

    .glitch {
        font-size: 24px;
    }

    .content {
        padding: 20px 15px;
    }

    .tab {
        min-width: 80px;
        padding: 12px 8px;
    }

    .tab-icon {
        font-size: 18px;
    }

    .tab-text {
        font-size: 10px;
    }

    .tip-options {
        grid-template-columns: repeat(2, 1fr);
    }

    .conversion-row {
        grid-template-columns: 1fr;
        gap: 15px;
    }

    .swap-btn {
        justify-self: center;
        margin: 10px auto;
    }

    .result-value {
        font-size: 36px;
    }

    #toast-container {
        right: 10px;
        left: 10px;
    }

    .toast {
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .glitch {
        font-size: 20px;
    }

    .subtitle {
        font-size: 12px;
    }

    h2 {
        font-size: 20px;
    }

    .result-value {
        font-size: 32px;
    }
}

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

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--primary);
    border-radius: 4px;
}

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

/* Print Styles */
@media print {
    body {
        background: white;
    }

    .back-button,
    .theme-toggle,
    .tabs,
    #particles {
        display: none;
    }

    .container {
        box-shadow: none;
    }
}