/* ============================================
   老年用户友好样式 (现代化版本)
   大字体、高对比度、清晰易读
   ============================================ */

/* 字体大小控制 */
:root {
    --font-size-base: 18px;
    --font-size-large: 20px;
    --font-size-xlarge: 24px;
    --line-height: 1.8;
    --letter-spacing: 0.3px;
}

/* 特大字体模式 */
[data-font-size="xlarge"] {
    --font-size-base: 24px;
    --font-size-large: 28px;
    --font-size-xlarge: 32px;
    --line-height: 1.9;
}

/* 大字体模式（默认） */
[data-font-size="large"] {
    --font-size-base: 20px;
    --font-size-large: 24px;
    --font-size-xlarge: 28px;
    --line-height: 1.8;
}

/* 标准字体 */
[data-font-size="normal"] {
    --font-size-base: 16px;
    --font-size-large: 18px;
    --font-size-xlarge: 20px;
    --line-height: 1.6;
}

/* 全局字体设置 */
body {
    font-size: var(--font-size-base);
    line-height: var(--line-height);
    letter-spacing: var(--letter-spacing);
}

/* 字体大小控制按钮现代化 */
.font-size-controls {
    display: flex;
    gap: 6px;
    padding: 4px 6px;
    background: var(--bg-secondary);
    border-radius: 28px;
    border: 1px solid var(--border-color);
    align-items: center;
    height: 44px;
}

.font-btn {
    width: 36px;
    height: 36px;
    border: none;
    background: transparent;
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.25s cubic-bezier(0.34, 1.56, 0.64, 1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    padding: 0;
    line-height: 1;
}

.font-btn-icon {
    width: 26px;
    height: 26px;
}

.font-btn:hover {
    background: var(--bg-hover);
    color: var(--primary-color);
    transform: scale(1.1);
}

.font-btn.active {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

/* 图片与文字配合展示现代化 */
.image-with-caption {
    margin: 28px 0;
    background: var(--bg-primary);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    border: 2px solid var(--border-color);
    transition: all 0.3s ease;
}

.image-with-caption:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
}

.guide-image {
    width: 100%;
    height: auto;
    display: block;
    cursor: zoom-in;
    transition: transform 0.4s ease;
}

.guide-image:hover {
    transform: scale(1.02);
}

.image-caption {
    padding: 18px 24px;
    background: var(--bg-primary);
    font-size: var(--font-size-large);
    font-weight: 600;
    color: var(--text-primary);
    text-align: center;
    border-top: 2px solid var(--border-color);
}

/* 步骤说明样式现代化 */
.step-description {
    font-size: var(--font-size-large);
    color: var(--text-secondary);
    margin-bottom: 24px;
    padding: 20px 24px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.08) 0%, rgba(59, 130, 246, 0.03) 100%);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary-color);
}

/* 重点提示框现代化 */
.key-points {
    background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
    border: 2px solid #f59e0b;
    border-radius: var(--border-radius-lg);
    padding: 28px;
    margin-top: 28px;
    box-shadow: var(--shadow);
}

[data-theme="dark"] .key-points {
    background: linear-gradient(135deg, #451a03 0%, #78350f 100%);
    border-color: #f59e0b;
}

.key-points h5 {
    font-size: var(--font-size-large);
    color: #92400e;
    margin-bottom: 18px;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: 10px;
}

[data-theme="dark"] .key-points h5 {
    color: #fcd34d;
}

.key-points h5::before {
    content: "⚠️";
    font-size: 1.3em;
}

.key-points ul {
    list-style: none;
    padding: 0;
}

.key-points li {
    font-size: var(--font-size-base);
    padding: 14px 0;
    padding-left: 40px;
    position: relative;
    border-bottom: 1px dashed rgba(0,0,0,0.1);
}

.key-points li:last-child {
    border-bottom: none;
}

.key-points li::before {
    content: "✓";
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    color: var(--secondary-color);
    font-weight: 900;
    font-size: 1.4em;
    width: 32px;
    height: 32px;
    background: rgba(16, 185, 129, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* 操作步骤框现代化 */
.instruction-box {
    background: linear-gradient(135deg, #e0f2fe 0%, #f0f9ff 100%);
    border: 2px solid var(--primary-color);
    border-radius: var(--border-radius-lg);
    padding: 28px;
    margin-top: 28px;
    box-shadow: var(--shadow);
}

[data-theme="dark"] .instruction-box {
    background: linear-gradient(135deg, #0c4a6e 0%, #164e63 100%);
}

.instruction-title {
    font-size: var(--font-size-large);
    font-weight: 800;
    color: var(--primary-dark);
    margin-bottom: 18px;
    display: flex;
    align-items: center;
    gap: 10px;
}

[data-theme="dark"] .instruction-title {
    color: #93c5fd;
}

.instruction-title::before {
    content: "📋";
    font-size: 1.2em;
}

.instruction-box ol {
    padding-left: 32px;
}

.instruction-box li {
    font-size: var(--font-size-base);
    padding: 12px 0;
    line-height: 1.9;
}

.instruction-box strong {
    color: var(--primary-dark);
    font-weight: 700;
}

[data-theme="dark"] .instruction-box strong {
    color: #93c5fd;
}

/* 提示框现代化 */
.tip-box {
    background: linear-gradient(135deg, #d1fae5 0%, #ecfdf5 100%);
    border: 2px solid var(--secondary-color);
    border-radius: var(--border-radius-lg);
    padding: 24px 28px;
    margin-top: 28px;
    font-size: var(--font-size-base);
    box-shadow: var(--shadow);
}

[data-theme="dark"] .tip-box {
    background: linear-gradient(135deg, #064e3b 0%, #065f46 100%);
}

.tip-box strong {
    color: #065f46;
    font-size: var(--font-size-large);
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

[data-theme="dark"] .tip-box strong {
    color: #6ee7b7;
}

.tip-box strong::before {
    content: "💡";
}

/* 解锁方式卡片现代化 */
.unlock-methods {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin-top: 28px;
}

.method-card {
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: 28px;
    text-align: center;
    transition: all 0.3s ease;
    box-shadow: var(--shadow);
}

.method-card:hover {
    border-color: var(--primary-color);
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
}

.method-icon {
    font-size: 3.5rem;
    display: block;
    margin-bottom: 18px;
    filter: drop-shadow(0 4px 6px rgba(0,0,0,0.1));
}

.method-card h5 {
    font-size: var(--font-size-large);
    color: var(--text-primary);
    margin-bottom: 12px;
    font-weight: 700;
}

.method-card p {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    line-height: 1.7;
}

/* 手势指南现代化 */
.gesture-guide {
    background: var(--bg-secondary);
    border-radius: var(--border-radius-lg);
    padding: 28px;
    margin-top: 28px;
    border: 1px solid var(--border-color);
}

.gesture-guide h5 {
    font-size: var(--font-size-large);
    margin-bottom: 24px;
    color: var(--text-primary);
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 10px;
}

.gesture-guide h5::before {
    content: "👆";
}

.gesture-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 16px;
}

.gesture-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 18px;
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    border: 2px solid var(--border-color);
    transition: all 0.25s ease;
}

.gesture-item:hover {
    border-color: var(--primary-light);
    transform: translateX(6px);
}

.gesture-icon {
    font-size: 2.2rem;
    min-width: 56px;
    text-align: center;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.1));
}

.gesture-name {
    font-weight: 700;
    font-size: var(--font-size-base);
    color: var(--text-primary);
    min-width: 90px;
}

.gesture-desc {
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    line-height: 1.6;
}

/* 键盘指南现代化 */
.phone-keypad-guide {
    background: linear-gradient(145deg, #1e293b 0%, #0f172a 100%);
    border-radius: 24px;
    padding: 28px;
    max-width: 320px;
    margin: 24px auto;
    box-shadow: var(--shadow-xl);
    border: 1px solid rgba(255,255,255,0.1);
}

.keypad-row {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 16px;
}

.keypad-key {
    width: 76px;
    height: 76px;
    background: rgba(255,255,255,0.1);
    border: 2px solid rgba(255,255,255,0.15);
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.6rem;
    font-weight: 700;
    transition: all 0.2s ease;
}

.keypad-key:hover {
    background: var(--primary-color);
    transform: scale(1.08);
}

.keypad-key small {
    font-size: 0.75rem;
    font-weight: 400;
    opacity: 0.8;
    margin-top: 2px;
}

/* 通话按钮指南现代化 */
.call-buttons-guide {
    display: flex;
    justify-content: center;
    gap: 24px;
    margin: 28px 0;
    flex-wrap: wrap;
}

.call-btn-demo {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    padding: 24px 32px;
    border-radius: var(--border-radius-lg);
    border: 3px solid;
    min-width: 140px;
    transition: all 0.25s ease;
    box-shadow: var(--shadow);
}

.call-btn-demo.green {
    background: linear-gradient(135deg, #d1fae5 0%, #ecfdf5 100%);
    border-color: var(--secondary-color);
}

.call-btn-demo.green:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(16, 185, 129, 0.3);
}

.call-btn-demo.red {
    background: linear-gradient(135deg, #fee2e2 0%, #fef2f2 100%);
    border-color: var(--danger-color);
}

.call-btn-demo.red:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(239, 68, 68, 0.3);
}

.call-btn-demo .btn-icon {
    font-size: 2.8rem;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.1));
}

.call-btn-demo .btn-text {
    font-size: var(--font-size-base);
    font-weight: 700;
}

/* 短信表单指南现代化 */
.sms-form-guide {
    background: var(--bg-secondary);
    border-radius: var(--border-radius-lg);
    padding: 28px;
    margin-top: 24px;
    border: 1px solid var(--border-color);
}

.form-field {
    margin-bottom: 24px;
}

.form-field label {
    display: block;
    font-size: var(--font-size-large);
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.input-demo, .textarea-demo {
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    padding: 16px;
    font-size: var(--font-size-base);
    color: var(--text-muted);
    width: 100%;
}

.textarea-demo {
    min-height: 120px;
}

/* 发送按钮指南 */
.send-button-guide {
    display: flex;
    justify-content: center;
    margin: 28px 0;
}

.send-btn-demo {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 44px;
    background: var(--primary-gradient);
    color: white;
    border-radius: 32px;
    font-size: var(--font-size-large);
    font-weight: 700;
    box-shadow: var(--shadow-lg);
    transition: all 0.25s ease;
}

.send-btn-demo:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-xl), 0 0 20px rgba(59, 130, 246, 0.3);
}

/* 图片查看器优化现代化 */
.image-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(15, 23, 42, 0.95);
    z-index: 4000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    backdrop-filter: blur(8px);
}

.image-modal-content {
    position: relative;
    width: 100%;
    max-width: 1200px;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.image-modal-wrapper {
    overflow: hidden;
    max-height: 80vh;
    background: var(--bg-primary);
    border-radius: var(--border-radius-lg);
    padding: 12px;
    box-shadow: var(--shadow-xl);
    cursor: grab;
    position: relative;
}

.image-modal-wrapper:active {
    cursor: grabbing;
}

.image-modal-wrapper img {
    max-width: 100%;
    height: auto;
    display: block;
    border-radius: var(--border-radius-sm);
    user-select: none;
    -webkit-user-drag: none;
}

.image-modal-wrapper img {
    max-width: 100%;
    height: auto;
    display: block;
    border-radius: var(--border-radius-sm);
}

.image-modal-close,
.image-modal-zoom-in,
.image-modal-zoom-out {
    position: fixed;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    border: 2px solid rgba(255, 255, 255, 0.3);
    background: rgba(30, 41, 59, 0.9);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.25s ease;
    z-index: 4001;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4), 0 0 0 1px rgba(255, 255, 255, 0.1);
    padding: 0;
    line-height: 1;
}

.image-modal-close {
    top: 24px;
    right: 24px;
}

.image-modal-zoom-in {
    bottom: 100px;
    right: 24px;
}

.image-modal-zoom-out {
    bottom: 36px;
    right: 24px;
}

.image-modal-close svg,
.image-modal-zoom-in svg,
.image-modal-zoom-out svg {
    width: 28px;
    height: 28px;
    stroke: white;
    stroke-width: 2.5;
    filter: drop-shadow(0 1px 2px rgba(0, 0, 0, 0.3));
}

.image-modal-close:hover,
.image-modal-zoom-in:hover,
.image-modal-zoom-out:hover {
    background: var(--primary-color);
    border-color: rgba(255, 255, 255, 0.5);
    color: white;
    transform: scale(1.1);
    box-shadow: 0 6px 24px rgba(59, 130, 246, 0.5), 0 0 0 1px rgba(255, 255, 255, 0.2);
}

.image-modal-close:active,
.image-modal-zoom-in:active,
.image-modal-zoom-out:active {
    transform: scale(0.95);
    box-shadow: 0 2px 12px rgba(59, 130, 246, 0.4);
}

.image-modal-caption {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    padding: 12px 28px;
    background: rgba(15, 23, 42, 0.85);
    border-radius: 24px;
    color: white;
    font-size: var(--font-size-base);
    font-weight: 500;
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    max-width: 80%;
    text-align: center;
    z-index: 4001;
}

.image-modal-caption:empty {
    display: none;
}

/* 章节标题优化 */
.section-title {
    font-size: 2.4rem;
    font-weight: 900;
    letter-spacing: -0.02em;
}

/* 步骤标题优化 */
.step-header h4 {
    font-size: 1.7rem;
    font-weight: 800;
}

/* 导航菜单优化 */
.nav-link {
    font-size: var(--font-size-base);
    font-weight: 600;
    padding: 14px 18px;
}

/* FAQ样式优化 */
.faq-question {
    font-size: var(--font-size-large);
    font-weight: 700;
    padding: 22px;
}

.faq-answer {
    font-size: var(--font-size-base);
}

.faq-answer ol {
    padding-left: 32px;
}

.faq-answer li {
    padding: 12px 0;
    line-height: 1.9;
}

/* 技巧卡片优化 */
.tip-card {
    border: 2px solid var(--border-color);
    padding: 28px;
}

.tip-header h4 {
    font-size: 1.5rem;
}

.tip-card p {
    font-size: var(--font-size-base);
    line-height: 1.9;
}

/* 介绍图片区域 */
.intro-images {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
    margin: 24px 0;
}

/* 响应式优化 */
@media screen and (max-width: 768px) {
    .font-size-controls {
        display: none;
    }
    
    .image-modal-zoom-in,
    .image-modal-zoom-out {
        display: none;
    }
    
    .image-modal-close {
        top: 16px;
        right: 16px;
        width: 52px;
        height: 52px;
        font-size: 1.4rem;
        background: rgba(0, 0, 0, 0.7);
    }
    
    .image-modal-wrapper {
        padding: 8px;
    }
    
    .image-modal-caption {
        font-size: var(--font-size-base);
        padding: 14px 24px;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .step-header h4 {
        font-size: 1.4rem;
    }
    
    .key-points,
    .instruction-box,
    .tip-box {
        padding: 20px;
    }
    
    .gesture-list {
        grid-template-columns: 1fr;
    }
    
    .gesture-item {
        flex-direction: column;
        text-align: center;
        gap: 10px;
    }
    
    .gesture-name {
        min-width: auto;
    }
    
    .call-buttons-guide {
        flex-direction: column;
        align-items: center;
    }
    
    .call-btn-demo {
        width: 100%;
        max-width: 200px;
    }
    
    .unlock-methods {
        grid-template-columns: 1fr;
    }
}

/* 高对比度模式支持 */
@media (prefers-contrast: high) {
    .image-with-caption {
        border-width: 3px;
    }
    
    .key-points,
    .instruction-box,
    .tip-box {
        border-width: 3px;
    }
    
    .step-description {
        border-left-width: 6px;
    }
    
    .method-card,
    .gesture-item {
        border-width: 3px;
    }
    
    .font-btn.active {
        outline: 2px solid currentColor;
        outline-offset: 2px;
    }
}

/* 触摸设备优化 */
@media (hover: none) and (pointer: coarse) {
    .image-with-caption:hover {
        transform: none;
    }
    
    .guide-image:hover {
        transform: none;
    }
    
    .keypad-key:hover {
        transform: none;
    }
    
    .call-btn-demo:hover {
        transform: none;
    }
    
    .send-btn-demo:hover {
        transform: none;
    }
    
    .gesture-item:hover {
        transform: none;
    }
    
    .method-card:hover {
        transform: none;
    }
    
    /* 增大触摸目标 */
    .font-btn {
        min-width: 48px;
        min-height: 48px;
    }
    
    .keypad-key {
        min-width: 64px;
        min-height: 64px;
    }
}