/**
 * Scientific Calculator Tool - Optimized Styles v2.0
 * Modern UI with GPU-accelerated animations
 */

:root {
    /* Core Colors */
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --primary-light: rgba(59, 130, 246, 0.12);
    --primary-glow: rgba(59, 130, 246, 0.35);
    --secondary-color: #8b5cf6;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --info-color: #0ea5e9;
    
    /* Theme Colors */
    --dark-bg: #0f172a;
    --dark-card: #1e293b;
    --dark-text: #f1f5f9;
    --light-bg: #f8fafc;
    --light-card: #ffffff;
    --light-text: #1e293b;
    
    /* Enhanced Layout */
    --border-radius: 10px;
    --border-radius-sm: 6px;
    --border-radius-lg: 16px;
    --box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
    --box-shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
    
    /* GPU-Optimized Transitions */
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Glass Effect */
    --glass-blur: blur(12px);
    --glass-bg: rgba(255, 255, 255, 0.85);
    --glass-border: rgba(255, 255, 255, 0.3);
    
    /* Borders */
    --border-color: #e2e8f0;
}

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

html {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
    background: linear-gradient(135deg, #f8fafc 0%, #e0f2fe 50%, #f0f9ff 100%);
    color: var(--light-text);
    transition: background var(--transition), color var(--transition-fast);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

body.dark-mode {
    background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #1e1b4b 100%);
    color: var(--dark-text);
    --glass-bg: rgba(30, 41, 59, 0.85);
    --glass-border: rgba(255, 255, 255, 0.08);
    --border-color: #334155;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 24px;
    flex: 1;
}

/* Header Styles - Glass Effect */
header {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    border-bottom: 1px solid var(--glass-border);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: all var(--transition-fast);
}

.dark-mode header {
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 14px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-container {
    display: flex;
    align-items: center;
}

.logo-container a {
    display: flex;
    align-items: center;
    text-decoration: none;
    gap: 12px;
}

.logo {
    height: 38px;
    transition: transform var(--transition);
}

.logo-container a:hover .logo {
    transform: scale(1.05) translateZ(0);
}

.site-title {
    font-size: 22px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
}

.nav-actions {
    display: flex;
    gap: 12px;
}

#theme-btn {
    background: var(--light-card);
    border: 1px solid var(--border-color);
    font-size: 16px;
    cursor: pointer;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
    color: var(--light-text);
    box-shadow: var(--box-shadow);
}

.dark-mode #theme-btn {
    color: var(--dark-text);
    background: var(--dark-card);
    border-color: #475569;
}

#theme-btn:hover {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-color: transparent;
    transform: rotate(20deg) scale(1.1) translateZ(0);
    box-shadow: 0 4px 14px var(--primary-glow);
}

/* Page Title - Enhanced */
.page-title {
    text-align: center;
    margin: 32px 0;
    animation: slideUp 0.5s ease-out;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

.page-title h1 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 8px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.03em;
}

.page-title p {
    font-size: 16px;
    color: #64748b;
}

.dark-mode .page-title p {
    color: #94a3b8;
}

/* Calculator Container - Enhanced */
.calculator-container {
    display: flex;
    flex-wrap: wrap;
    gap: 32px;
    justify-content: center;
    margin: 40px auto;
    max-width: 1000px;
}

.calculator {
    background: var(--light-card);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--box-shadow-lg);
    border: 1px solid var(--border-color);
    padding: 24px;
    width: 100%;
    max-width: 520px;
    transition: all var(--transition);
}

.calculator:hover {
    transform: translateY(-4px) translateZ(0);
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.15);
}

.dark-mode .calculator {
    background: var(--dark-card);
}

.display-container {
    background: linear-gradient(135deg, #f8fafc, #f1f5f9);
    border-radius: var(--border-radius);
    margin-bottom: 24px;
    padding: 20px;
    text-align: right;
    box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.06);
    border: 1px solid var(--border-color);
}

.dark-mode .display-container {
    background: linear-gradient(135deg, #0f172a, #1e293b);
    box-shadow: inset 0 2px 6px rgba(0, 0, 0, 0.3);
}

.history {
    color: #64748b;
    font-size: 14px;
    min-height: 22px;
    margin-bottom: 8px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-family: 'JetBrains Mono', 'Consolas', monospace;
}

.dark-mode .history {
    color: #94a3b8;
}

.display {
    font-size: 42px;
    font-weight: 700;
    overflow: hidden;
    text-overflow: ellipsis;
    min-height: 54px;
    font-family: 'JetBrains Mono', 'Consolas', monospace;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.dark-mode .display {
    background: linear-gradient(135deg, #93c5fd, #c4b5fd);
    -webkit-background-clip: text;
    background-clip: text;
}

.button-container {
    display: grid;
    gap: 10px;
}

.button-row {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 10px;
}

.btn {
    background: var(--light-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    color: var(--light-text);
    cursor: pointer;
    font-size: 17px;
    font-weight: 600;
    padding: 16px 12px;
    transition: all var(--transition-fast);
    user-select: none;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle, var(--primary-color) 0%, transparent 70%);
    opacity: 0;
    transform: scale(0.5);
    transition: opacity var(--transition-fast), transform var(--transition-fast);
}

.btn:active::before {
    opacity: 0.15;
    transform: scale(1.5);
}

.dark-mode .btn {
    background: #334155;
    color: var(--dark-text);
    border-color: #475569;
}

.btn:hover {
    transform: translateY(-3px) translateZ(0);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
}

.btn:active {
    transform: translateY(0) translateZ(0);
    box-shadow: none;
}

.function {
    background: linear-gradient(135deg, #e2e8f0, #f1f5f9);
    font-weight: 600;
}

.dark-mode .function {
    background: linear-gradient(135deg, #475569, #334155);
}

.number {
    background: var(--light-card);
}

.dark-mode .number {
    background: #1e293b;
}

.operator {
    background: linear-gradient(135deg, #dbeafe, #e0f2fe);
    color: var(--primary-color);
    font-weight: 700;
    border-color: #bfdbfe;
}

.dark-mode .operator {
    background: linear-gradient(135deg, #1e3a8a, #1e40af);
    color: #93c5fd;
    border-color: #1d4ed8;
}

.equals {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    font-weight: 700;
    border: none;
    box-shadow: 0 4px 14px var(--primary-glow);
}

.equals:hover {
    box-shadow: 0 6px 20px var(--primary-glow);
}

.memory {
    background: linear-gradient(135deg, #ede9fe, #f5f3ff);
    color: var(--secondary-color);
    font-size: 13px;
    font-weight: 600;
}

.dark-mode .memory {
    background: linear-gradient(135deg, #4c1d95, #5b21b6);
    color: #ddd6fe;
}

.calculator-info {
    background: var(--light-card);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--box-shadow);
    border: 1px solid var(--border-color);
    padding: 24px;
    width: 100%;
    max-width: 400px;
}

.dark-mode .calculator-info {
    background: var(--dark-card);
}

.calculator-info h3 {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 14px;
    font-size: 17px;
    font-weight: 700;
}

.calculator-info ul {
    list-style-type: none;
    margin-bottom: 20px;
}

.calculator-info li {
    margin-bottom: 8px;
    font-size: 14px;
    color: #64748b;
    padding-left: 16px;
    position: relative;
}

.calculator-info li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

.dark-mode .calculator-info li {
    color: #94a3b8;
}

.calculator-info strong {
    color: var(--light-text);
    font-weight: 600;
}

.dark-mode .calculator-info strong {
    color: var(--dark-text);
}

/* Footer - Glassmorphism */
.footer {
    margin-top: 50px;
    padding: 24px 0;
    text-align: center;
    border-top: 1px solid rgba(226, 232, 240, 0.5);
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transition: all var(--transition);
}

.dark-mode .footer {
    background: rgba(31, 41, 55, 0.85);
    border-top-color: rgba(75, 85, 99, 0.5);
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.footer p {
    margin: 10px 0;
    font-size: 14px;
    color: #64748b;
}

.dark-mode .footer p {
    color: #94a3b8;
}

.footer-links {
    line-height: 1.8;
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
    transition: all var(--transition-fast);
    position: relative;
}

.footer a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transition: width var(--transition);
}

.footer a:hover::after {
    width: 100%;
}

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

/* Responsive - Enhanced */
@media (max-width: 768px) {
    .calculator-container {
        flex-direction: column;
        align-items: center;
        gap: 24px;
        margin: 24px auto;
        padding: 0 16px;
    }
    
    .calculator {
        padding: 20px;
    }
    
    .button-row {
        gap: 8px;
    }
    
    .btn {
        font-size: 15px;
        padding: 14px 10px;
    }
    
    .display {
        font-size: 32px;
    }
    
    .calculator-info {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .button-row {
        gap: 6px;
    }
    
    .btn {
        font-size: 14px;
        padding: 12px 6px;
        border-radius: 8px;
    }
    
    .memory {
        font-size: 11px;
    }
    
    .display {
        font-size: 26px;
    }
    
    .display-container {
        padding: 16px;
    }
    
    .page-title {
        font-size: 1.5rem;
    }
}

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