/**
 * Responsive Design - Mobile-first approach
 * Optimized for all device sizes
 */

/* Base mobile styles are in main.css */

/* Small tablets and large phones (768px and up) */
@media (min-width: 768px) {
    .container {
        padding: 0 var(--space-8);
    }
    
    .hero-title {
        font-size: 3.5rem;
    }
    
    .form-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .results-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .steps-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Medium tablets and small desktops (1024px and up) */
@media (min-width: 1024px) {
    .container {
        padding: 0 var(--space-10);
    }
    
    .hero-title {
        font-size: 4rem;
    }
    
    .form-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .results-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .steps-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .faq-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Large desktops (1200px and up) */
@media (min-width: 1200px) {
    .container {
        max-width: 1200px;
    }
    
    .hero-title {
        font-size: 4.5rem;
    }
}

/* Mobile-specific optimizations */
@media (max-width: 767px) {
    /* Typography adjustments - simplified and efficient */
    h1 {
        font-size: 1.875rem;
        line-height: 1.2;
        margin-bottom: var(--space-3);
    }
    
    h2 {
        font-size: 1.5rem;
        line-height: 1.3;
        margin-bottom: var(--space-3);
    }
    
    h3 {
        font-size: 1.125rem;
        line-height: 1.4;
        margin-bottom: var(--space-2);
    }
    
    .hero-title {
        font-size: 2rem;
        line-height: 1.2;
        margin-bottom: var(--space-4);
    }
    
    .hero-subtitle {
        font-size: 1rem;
        line-height: 1.5;
    }
    
    /* Layout adjustments - streamlined */
    .hero {
        padding: var(--space-10) 0;
    }
    
    .hero-features {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-3);
        margin-top: var(--space-6);
    }
    
    .feature {
        padding: var(--space-2) var(--space-3);
        font-size: 0.8rem;
        border-radius: var(--rounded-md);
    }
    
    .feature-icon {
        font-size: 1rem;
    }
    
    /* Calculator form optimizations - cleaner and more efficient */
    .calculator-container {
        padding: var(--space-4);
        margin: var(--space-3) 0;
        border-radius: var(--rounded-lg);
        box-shadow: var(--shadow-md);
    }
    
    .form-grid {
        grid-template-columns: 1fr;
        gap: var(--space-3);
    }
    
    .form-section {
        margin-bottom: var(--space-6);
    }
    
    .section-title {
        font-size: 1.125rem;
        margin-bottom: var(--space-3);
        color: var(--gray-900);
        font-weight: 600;
    }
    
    .input-group label {
        font-size: 0.875rem;
        font-weight: 500;
        margin-bottom: var(--space-1);
        display: block;
    }
    
    .input-group input,
    .input-group select {
        padding: var(--space-3);
        font-size: 0.95rem;
        border: 1px solid var(--gray-300);
        border-radius: var(--rounded-md);
        width: 100%;
        transition: border-color var(--transition-base);
    }
    
    .input-group input:focus,
    .input-group select:focus {
        border-color: var(--primary-color);
        box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
    }
    
    /* Results optimizations - compact and efficient */
    .results-grid {
        grid-template-columns: 1fr;
        gap: var(--space-3);
    }
    
    .result-card {
        padding: var(--space-3);
        display: flex;
        align-items: center;
        gap: var(--space-3);
        background: white;
        border-radius: var(--rounded-lg);
        box-shadow: var(--shadow-sm);
        border: 1px solid var(--gray-200);
    }
    
    .result-icon {
        font-size: 1.5rem;
        flex-shrink: 0;
    }
    
    .result-content {
        flex: 1;
    }
    
    .result-label {
        font-size: 0.75rem;
        color: var(--gray-600);
        margin-bottom: var(--space-1);
        text-transform: uppercase;
        font-weight: 500;
        letter-spacing: 0.05em;
    }
    
    .result-value {
        font-size: 1.125rem;
        line-height: 1.2;
        font-weight: 700;
        color: var(--gray-900);
    }
    
    .result-description {
        font-size: 0.7rem;
        color: var(--gray-500);
        margin-top: var(--space-1);
    }
    
    .detailed-breakdown {
        padding: var(--space-6);
    }
    
    .calculation-step {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-1);
    }
    
    .calculation-step .value {
        align-self: flex-end;
        font-size: 0.9rem;
    }
    
    /* Button optimizations - streamlined */
    .results-actions {
        flex-direction: column;
        gap: var(--space-2);
        margin-top: var(--space-6);
    }
    
    .results-actions .btn {
        width: 100%;
        justify-content: center;
    }
    
    .btn {
        padding: var(--space-4) var(--space-4);
        font-size: 0.95rem;
        font-weight: 600;
        border-radius: var(--rounded-lg);
        min-height: 56px; /* 统一触摸友好尺寸 */
        display: flex;
        align-items: center;
        justify-content: center;
        line-height: 1.2;
    }
    
    .btn-primary {
        background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
        border: none;
        box-shadow: var(--shadow-sm);
    }
    
    .btn-primary:hover {
        transform: translateY(-1px);
        box-shadow: var(--shadow-md);
    }
    
    /* Navigation optimizations - improved mobile UX */
    .site-header {
        padding: var(--space-3) 0;
        box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    }
    
    .header-content {
        flex-direction: row;
        justify-content: space-between;
        align-items: center;
        gap: var(--space-2);
    }
    
    .logo h2 {
        font-size: 1.125rem !important;
        margin: 0;
    }
    
    .main-nav {
        display: none;
    }
    
    /* Show mobile nav when opened */
    .main-nav.mobile-open {
        display: block !important;
    }
    
    /* Mobile menu toggle */
    .mobile-menu-toggle {
        display: flex;
        flex-direction: column;
        cursor: pointer;
        padding: var(--space-2);
        border-radius: var(--rounded-md);
        background: rgba(255, 255, 255, 0.1);
        border: 1px solid rgba(255, 255, 255, 0.2);
    }
    
    .mobile-menu-toggle span {
        width: 20px;
        height: 2px;
        background: white;
        margin: 1px 0;
        transition: all var(--transition-base);
        border-radius: 1px;
    }
    
    .mobile-nav-overlay {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: rgba(0, 0, 0, 0.5);
        backdrop-filter: blur(4px);
        z-index: 1001;
        display: none;
    }
    
    .mobile-nav-menu {
        position: fixed;
        top: 0;
        right: -300px;
        width: 280px;
        height: 100vh;
        background: white;
        box-shadow: var(--shadow-2xl);
        padding: var(--space-6);
        z-index: 1002;
        transition: right var(--transition-base);
    }
    
    .mobile-nav-menu.open {
        right: 0;
    }
    
    .mobile-nav-menu ul {
        list-style: none;
        padding: 0;
        margin: var(--space-8) 0 0 0;
    }
    
    .mobile-nav-menu li {
        margin-bottom: var(--space-1);
    }
    
    .mobile-nav-menu a {
        display: block;
        padding: var(--space-3) var(--space-4);
        color: var(--gray-800);
        text-decoration: none;
        border-radius: var(--rounded-md);
        font-weight: 500;
        transition: all var(--transition-base);
    }
    
    .mobile-nav-menu a:hover,
    .mobile-nav-menu a.active {
        background: var(--primary-color);
        color: white;
    }
    
    /* Step cards mobile layout - more compact */
    .steps-grid {
        grid-template-columns: 1fr;
        gap: var(--space-4);
    }
    
    .step-card {
        padding: var(--space-4);
        display: flex;
        align-items: flex-start;
        gap: var(--space-3);
        text-align: left;
    }
    
    .step-number {
        width: 2rem;
        height: 2rem;
        font-size: 0.875rem;
        flex-shrink: 0;
        margin-bottom: 0;
    }
    
    .step-content {
        flex: 1;
    }
    
    .step-content h3 {
        font-size: 1rem;
        margin-bottom: var(--space-2);
    }
    
    .step-content p {
        font-size: 0.875rem;
        line-height: 1.5;
    }
    
    /* Feature cards mobile layout - simplified grid */
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-4);
    }
    
    .feature-card {
        padding: var(--space-4);
        text-align: center;
    }
    
    .feature-icon-large {
        font-size: 2rem;
        margin-bottom: var(--space-2);
    }
    
    .feature-card h3 {
        font-size: 0.95rem;
        margin-bottom: var(--space-2);
    }
    
    .feature-card p {
        font-size: 0.8rem;
        line-height: 1.4;
    }
    
    /* FAQ mobile layout - accordion style */
    .faq-grid {
        grid-template-columns: 1fr;
        gap: var(--space-3);
    }
    
    .faq-item {
        padding: var(--space-4);
        border: 1px solid var(--gray-200);
        border-radius: var(--rounded-lg);
        background: white;
    }
    
    .faq-item h3 {
        font-size: 1rem;
        margin-bottom: var(--space-3);
        padding-right: var(--space-6);
        position: relative;
    }
    
    .faq-item h3::after {
        content: '+';
        position: absolute;
        right: 0;
        top: 0;
        font-weight: normal;
        color: var(--primary-color);
    }
    
    .faq-item p {
        font-size: 0.875rem;
        line-height: 1.6;
    }
    
    /* Footer mobile layout - simplified */
    .site-footer {
        padding: var(--space-10) 0 var(--space-6);
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: var(--space-4);
    }
    
    .footer-section {
        margin-bottom: var(--space-4);
    }
    
    .footer-section h3,
    .footer-section h4 {
        font-size: 1rem;
        margin-bottom: var(--space-2);
    }
    
    .footer-section ul {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: var(--space-3) var(--space-4);
    }
    
    .footer-section ul a {
        font-size: 0.875rem;
    }
    
    .disclaimer-notice {
        padding: var(--space-3);
        margin-bottom: var(--space-3);
    }
    
    .disclaimer-notice p {
        font-size: 0.8rem;
        line-height: 1.5;
    }
    
    /* Progress steps mobile */
    .progress-steps {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-2);
    }
    
    .progress-line {
        display: none;
    }
    
    /* Error and success messages */
    .error-message,
    .success-message,
    .info-message {
        font-size: 0.875rem;
        padding: var(--space-3);
    }
    
    /* Input help text and validation */
    .input-help {
        font-size: 0.75rem;
        color: var(--gray-500);
        margin-top: var(--space-1);
        line-height: 1.3;
    }
    
    .input-wrapper {
        position: relative;
    }
    
    .input-prefix {
        position: absolute;
        left: var(--space-3);
        top: 50%;
        transform: translateY(-50%);
        color: var(--gray-500);
        font-size: 0.875rem;
        pointer-events: none;
        z-index: 1;
    }
    
    .input-wrapper input {
        padding-left: calc(var(--space-6) + 0.5rem);
    }
    
    .gain-preview {
        font-size: 0.75rem;
        color: var(--success-color);
        margin-top: var(--space-1);
        font-weight: 500;
    }
    
    /* Tooltips mobile adjustments */
    .tooltip::after {
        position: relative;
        transform: none;
        left: auto;
        bottom: auto;
        display: block;
        margin-top: var(--space-1);
        white-space: normal;
        opacity: 1;
        visibility: visible;
        background-color: var(--gray-100);
        color: var(--gray-700);
        border: 1px solid var(--gray-300);
    }
    
    /* Loading states mobile */
    .loading::after {
        width: 16px;
        height: 16px;
        margin: -8px 0 0 -8px;
    }
}

/* Extra small devices (less than 375px) - ultra-compact */
@media (max-width: 374px) {
    .container {
        padding: 0 var(--space-3);
    }
    
    .calculator-container {
        padding: var(--space-3);
        margin: var(--space-2) 0;
    }
    
    .hero {
        padding: var(--space-8) 0;
    }
    
    .hero-title {
        font-size: 1.75rem;
        line-height: 1.1;
    }
    
    .hero-features {
        grid-template-columns: 1fr;
        gap: var(--space-2);
    }
    
    .feature {
        padding: var(--space-2);
        font-size: 0.75rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
        gap: var(--space-3);
    }
    
    .feature-card {
        padding: var(--space-3);
    }
    
    .feature-icon-large {
        font-size: 1.5rem;
    }
    
    .result-card {
        padding: var(--space-2);
        gap: var(--space-2);
    }
    
    .result-value {
        font-size: 1rem;
    }
    
    .btn {
        padding: var(--space-2) var(--space-3);
        font-size: 0.8rem;
        min-height: 40px;
    }
    
    .section-title {
        font-size: 1rem;
    }
    
    .step-card {
        padding: var(--space-3);
        gap: var(--space-2);
    }
    
    .step-number {
        width: 1.75rem;
        height: 1.75rem;
        font-size: 0.75rem;
    }
}

/* Landscape phone optimization */
@media (max-width: 767px) and (orientation: landscape) {
    .hero {
        padding: var(--space-8) 0;
    }
    
    .hero-title {
        font-size: 2.25rem;
    }
    
    .calculator-section {
        padding: var(--space-8) 0;
    }
    
    .results-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* High DPI displays */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    /* Optimize for retina displays */
    .result-icon,
    .feature-icon,
    .feature-icon-large {
        image-rendering: crisp-edges;
    }
}

/* Print styles */
@media print {
    /* Hide unnecessary elements when printing */
    .site-header,
    .site-footer,
    .results-actions,
    button {
        display: none;
    }
    
    /* Optimize layout for print */
    .container {
        max-width: none;
        padding: 0;
    }
    
    .results-container {
        box-shadow: none;
        border: 1px solid var(--gray-300);
        background: white;
        color: var(--gray-900);
    }
    
    .result-card {
        border: 1px solid var(--gray-300);
        background: white;
        color: var(--gray-900);
    }
    
    .detailed-breakdown {
        background: white;
        border: 1px solid var(--gray-300);
        color: var(--gray-900);
    }
    
    /* Ensure good contrast for printing */
    .calculation-step .label,
    .calculation-step .value,
    .result-label,
    .result-value {
        color: var(--gray-900);
    }
    
    /* Page breaks */
    .detailed-breakdown {
        page-break-inside: avoid;
    }
    
    .breakdown-section {
        page-break-inside: avoid;
        margin-bottom: var(--space-6);
    }
}

/* Accessibility enhancements */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    
    .result-card:hover {
        transform: none;
    }
    
    .step-card:hover,
    .feature-card:hover {
        transform: none;
    }
}