/* ============================================
   VARIABLES & RESET
   ============================================ */
:root {
    /* Colors */
    --primary: #667eea;
    --primary-dark: #5568d3;
    --primary-light: #764ba2;
    --secondary: #f093fb;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #3b82f6;
    
    /* Grays */
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 0.75rem;
    --spacing-lg: 1rem;
    --spacing-xl: 1.25rem;
    --spacing-2xl: 1.5rem;
    
    /* Typography */
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, 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;
    
    /* 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);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
}

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

body {
    font-family: var(--font-family);
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    min-height: 100vh;
    color: var(--gray-800);
    line-height: 1.6;
}

/* ============================================
   APP CONTAINER
   ============================================ */
.app-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    min-height: 100vh;
}

/* ============================================
   HEADER
   ============================================ */
.app-header {
    background: linear-gradient(135deg, #ffffff 0%, #f8f9ff 100%);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl) var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    box-shadow: 0 10px 40px rgba(102, 126, 234, 0.15), 0 2px 8px rgba(0, 0, 0, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.8);
    position: relative;
    overflow: hidden;
    width: 100%;
    box-sizing: border-box;
}

.app-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary) 0%, var(--primary-light) 50%, var(--primary) 100%);
}

.header-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-lg);
    width: 100%;
    max-width: 100%;
}

.header-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-lg);
    text-align: center;
    width: 100%;
    flex-wrap: wrap;
}

.logo-icon {
    width: 140px;
    height: 140px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.logo-image {
    width: 100%;
    height: 100%;
    object-fit: contain;
    filter: drop-shadow(0 2px 8px rgba(102, 126, 234, 0.2));
}

.logo-text {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    text-align: center;
    flex: 1;
    min-width: 0;
}

.app-title {
    font-size: 2.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin: 0;
    letter-spacing: -0.02em;
    line-height: 1.1;
}

.app-subtitle {
    font-size: var(--font-size-base);
    color: var(--gray-600);
    font-weight: 500;
    margin: 0;
    letter-spacing: 0.01em;
}

.header-badge {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    justify-content: center;
}

.badge-text {
    display: inline-flex;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-lg);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
    border: 1px solid rgba(102, 126, 234, 0.2);
    border-radius: 50px;
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--primary);
    white-space: nowrap;
}

@media (max-width: 768px) {
    .header-logo {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-md);
    }
    
    .logo-icon {
        width: 105px;
        height: 105px;
    }
    
    .app-title {
        font-size: 2rem;
    }
    
    .header-badge {
        gap: var(--spacing-sm);
    }
    
    .badge-text {
        font-size: var(--font-size-xs);
        padding: var(--spacing-xs) var(--spacing-md);
    }
}

/* ============================================
   TABS NAVIGATION
   ============================================ */
.tabs-nav {
    display: flex;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-lg);
    padding: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    gap: var(--spacing-sm);
}

.tab-btn {
    flex: 1;
    padding: var(--spacing-md) var(--spacing-lg);
    background: transparent;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--gray-600);
    transition: all var(--transition-base);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.tab-btn:hover {
    background: var(--gray-100);
    color: var(--gray-800);
}

.tab-btn.active {
    background: white;
    color: var(--primary);
    box-shadow: var(--shadow-sm);
}

.tab-icon {
    font-size: 1.25rem;
}

/* ============================================
   MAIN CONTENT
   ============================================ */
.main-content {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-xl);
    min-height: 500px;
}

.tab-panel {
    display: none;
    animation: fadeIn var(--transition-slow);
}

.tab-panel.active {
    display: block;
}

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

.panel-header {
    margin-bottom: var(--spacing-lg);
}

.panel-header h2 {
    font-size: var(--font-size-2xl);
    color: var(--gray-900);
    margin-bottom: var(--spacing-sm);
}

.panel-description {
    color: var(--gray-600);
    font-size: var(--font-size-base);
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
    .app-container {
        padding: var(--spacing-md);
    }
    
    .tabs-nav {
        flex-direction: column;
    }
    
    .app-title {
        font-size: var(--font-size-2xl);
        flex-direction: column;
    }
    
    .app-title .icon {
        font-size: 2rem;
    }
}