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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 20px;
}

body.mobile-landing {
    background: #fff;
    padding: 0;
}

.mobile-container {
    max-width: 640px;
}

body.mobile-landing .container.mobile-container {
    max-width: 100%;
    margin: 0;
    border-radius: 0;
    box-shadow: none;
    min-height: 100vh;
}

.mobile-hero {
    background: linear-gradient(135deg, #0f8bff 0%, #6b73ff 100%);
    color: #fff;
    padding: 50px 30px;
    text-align: left;
}

.mobile-hero h1 {
    font-size: 2.4em;
    margin-bottom: 10px;
}

body.mobile-landing .mobile-hero {
    padding: 32px 20px;
}

body.mobile-landing .mobile-hero h1 {
    font-size: 1.85em;
}

.hero-badge {
    display: inline-block;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.4);
    border-radius: 999px;
    padding: 6px 16px;
    font-size: 0.9em;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-bottom: 15px;
}

.mobile-content {
    padding: 30px;
}

body.mobile-landing .mobile-content {
    padding: 22px 20px;
}

.mobile-section {
    border-bottom: 1px solid #eee;
    padding-bottom: 30px;
    margin-bottom: 30px;
}

body.mobile-landing .mobile-section {
    margin-bottom: 20px;
    padding-bottom: 20px;
}

.mobile-section:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.mobile-section h2 {
    color: #0f8bff;
    font-size: 1.6em;
    margin-bottom: 10px;
}

body.mobile-landing .mobile-section h2 {
    font-size: 1.35em;
}

.apk-btn {
    display: inline-block;
    width: 100%;
    text-align: center;
    background: #0f8bff;
    color: #fff;
    padding: 15px;
    border-radius: 10px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1em;
    margin: 20px 0 10px;
    box-shadow: 0 12px 20px rgba(15, 139, 255, 0.25);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

body.mobile-landing .apk-btn {
    padding: 12px;
    font-size: 1em;
    box-shadow: 0 8px 14px rgba(15, 139, 255, 0.2);
}

.apk-btn:active {
    transform: translateY(1px);
    box-shadow: 0 8px 12px rgba(15, 139, 255, 0.2);
}

.apk-meta {
    font-size: 0.9em;
    color: #666;
}

.instruction-list {
    margin-left: 20px;
    color: #444;
}

.instruction-list li {
    margin-bottom: 12px;
}

body.mobile-landing .instruction-list {
    margin-left: 0;
}

body.mobile-landing .instruction-list li {
    margin-bottom: 16px;
}

body.mobile-landing .substep-list {
    list-style: none;
    padding-left: 0;
    counter-reset: substep;
}

body.mobile-landing .substep-list li {
    position: relative;
    padding-left: 52px;
    margin-bottom: 18px;
}

body.mobile-landing .substep-list li::before {
    counter-increment: substep;
    content: counter(substep);
    position: absolute;
    left: 0;
    top: 0.15em;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: #1a73e8;
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
}

body.mobile-landing .substep-list span {
    font-weight: 600;
    color: #12263f;
    display: block;
    margin-bottom: 4px;
}

body.mobile-landing .substep-list p {
    margin: 0;
    color: #4b5d73;
}

body.mobile-landing .launcher-note {
    color: #4b5d73;
    font-size: 0.95em;
    margin-top: 6px;
}

.tip-card,
.important-card {
    background: #f5faff;
    border: 1px solid #d5e7ff;
    padding: 15px;
    border-radius: 10px;
    margin-top: 15px;
    color: #22527a;
}

body.mobile-landing .tip-card,
body.mobile-landing .important-card {
    margin-top: 12px;
    padding: 12px 14px;
}

.usage-list {
    list-style: none;
    padding-left: 0;
}

.usage-list li {
    display: flex;
    gap: 15px;
    margin-bottom: 18px;
    align-items: flex-start;
}

.usage-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: #0f8bff;
    color: #fff;
    font-weight: bold;
    flex-shrink: 0;
}

.mobile-questions .question-card {
    border: 1px solid #e4e9f2;
    border-radius: 12px;
    padding: 18px;
    margin-bottom: 16px;
    background: #fdfdff;
}

.question-text {
    font-weight: 600;
    margin-bottom: 10px;
}

.question-actions {
    display: flex;
    gap: 10px;
}

.question-actions button {
    flex: 1;
    padding: 10px;
    border-radius: 20px;
    border: 1px solid #cfd8ff;
    background: #fff;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.question-actions button.selected {
    background: #0f8bff;
    color: #fff;
    border-color: #0f8bff;
}

.question-followup {
    margin-top: 12px;
    color: #3d4a5c;
    font-size: 0.95em;
    display: none;
}

.question-followup.visible {
    display: block;
}

.mobile-help p {
    color: #4b5d73;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: white;
    border-radius: 12px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    overflow: hidden;
}

.header {
    background: linear-gradient(135deg, #1a73e8 0%, #1557b0 100%);
    color: white;
    padding: 40px;
    text-align: center;
}

.header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
}

.header p {
    font-size: 1.2em;
    opacity: 0.9;
}

.content {
    padding: 40px;
}

.download-section {
    background: #f0f7ff;
    border: 2px solid #1a73e8;
    border-radius: 8px;
    padding: 30px;
    margin-bottom: 40px;
    text-align: center;
}

.download-btn {
    display: inline-block;
    background: #1a73e8;
    color: white;
    padding: 15px 40px;
    border-radius: 6px;
    text-decoration: none;
    font-size: 1.2em;
    font-weight: 600;
    transition: background 0.3s;
    margin-top: 15px;
}

.download-btn:hover {
    background: #1557b0;
}

.extensions-btn {
    display: inline-block;
    background: #28a745;
    color: white;
    padding: 12px 30px;
    border-radius: 6px;
    text-decoration: none;
    font-size: 1.1em;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all 0.3s;
    margin: 10px 0;
}

.extensions-btn:hover {
    background: #218838;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.extensions-btn:active {
    transform: translateY(0);
}

.extensions-btn.copied {
    background: #007bff;
    animation: pulse 0.3s;
}

@keyframes pulse {

    0%,
    100% {
        transform: scale(1);
    }

    50% {
        transform: scale(1.05);
    }
}

.section {
    margin-bottom: 40px;
}

.section h2 {
    color: #1a73e8;
    font-size: 1.8em;
    margin-bottom: 20px;
    border-bottom: 2px solid #e0e0e0;
    padding-bottom: 10px;
}

.section h3 {
    color: #333;
    font-size: 1.3em;
    margin-top: 25px;
    margin-bottom: 15px;
}

.step {
    background: #f8f9fa;
    border-left: 4px solid #1a73e8;
    padding: 20px;
    margin-bottom: 20px;
    border-radius: 4px;
}

.step-number {
    display: inline-block;
    background: #1a73e8;
    color: white;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    text-align: center;
    line-height: 30px;
    font-weight: bold;
    margin-right: 10px;
}

.step-title {
    font-weight: 600;
    font-size: 1.1em;
    margin-bottom: 10px;
}

.step-detail {
    margin-left: 40px;
    color: #555;
}

code {
    background: #f4f4f4;
    padding: 2px 6px;
    border-radius: 3px;
    font-family: 'Courier New', monospace;
    color: #e83e8c;
}

.important {
    background: #fff3cd;
    border-left: 4px solid #ffc107;
    padding: 15px;
    margin: 20px 0;
    border-radius: 4px;
}

.tip {
    background: #d4edda;
    border-left: 4px solid #28a745;
    padding: 15px;
    margin: 20px 0;
    border-radius: 4px;
}

details {
    margin: 20px 0;
}

details summary {
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

ul {
    margin-left: 40px;
    margin-top: 10px;
    margin-bottom: 10px;
}

li {
    margin-bottom: 8px;
}

.footer {
    background: #f8f9fa;
    padding: 20px 40px;
    text-align: center;
    color: #666;
    border-top: 1px solid #e0e0e0;
}