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

html {
    -webkit-tap-highlight-color: transparent;
}

button, a, input, label, [role="button"] {
    -webkit-tap-highlight-color: transparent;
    tap-highlight-color: transparent;
}

body.install-page {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background: #1c1c1c;
    color: #d1d5db;
    margin: 0;
    min-height: 100vh;
    overflow-x: hidden;
}

.install-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 16px;
    border-bottom: 1px solid #2a2a2a;
    background: #1c1c1c;
    position: sticky;
    top: 0;
    z-index: 10;
}

.install-header h1 {
    margin: 0;
    font-size: 0.95rem;
    color: #ececec;
}

.install-header a {
    color: #4ade80;
    text-decoration: none;
    font-size: 0.85rem;
}

.install-main {
    max-width: 480px;
    margin: 0 auto;
    padding: 28px 20px 48px;
    text-align: center;
}

.install-logo {
    width: 88px;
    height: 88px;
    border-radius: 20px;
    margin-bottom: 16px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
}

.install-main h2 {
    margin: 0 0 8px;
    font-size: 1.45rem;
    color: #f0f0f0;
}

.install-sub {
    margin: 0 0 24px;
    font-size: 0.9rem;
    color: #94a3b8;
    line-height: 1.5;
}

.install-about {
    margin: 0 0 12px;
    font-size: 0.92rem;
    color: #b0b0b0;
    line-height: 1.55;
    max-width: 400px;
    margin-left: auto;
    margin-right: auto;
}

.install-lang {
    margin-bottom: 20px;
    font-size: 0.82rem;
}

.install-lang button {
    background: none;
    border: none;
    color: #64748b;
    cursor: pointer;
    font-family: inherit;
    font-size: inherit;
    padding: 0 4px;
}

.install-lang button.active {
    color: #4ade80;
    font-weight: 600;
}

.install-card {
    background: #242424;
    border: 1px solid #333;
    border-radius: 14px;
    padding: 20px;
    text-align: left;
    margin-bottom: 20px;
}

.install-card h3 {
    margin: 0 0 12px;
    font-size: 1rem;
    color: #e2e8f0;
}

.install-steps {
    margin: 0;
    padding-left: 1.2rem;
}

.install-steps li {
    margin-bottom: 10px;
    font-size: 0.9rem;
    line-height: 1.55;
    color: #94a3b8;
}

.install-steps li:last-child {
    margin-bottom: 0;
}

.install-note {
    margin: 14px 0 0;
    padding: 10px 12px;
    background: #1a1a1a;
    border-radius: 8px;
    font-size: 0.82rem;
    color: #888;
    line-height: 1.45;
}

.install-actions {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 8px;
}

#install-btn {
    background: #4ade80;
    color: #111;
    border: none;
    border-radius: 10px;
    padding: 14px 20px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
}

#install-btn:hover {
    background: #6ee8a0;
}

#install-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.install-continue {
    color: #64748b;
    text-decoration: none;
    font-size: 0.85rem;
}

.install-continue:hover {
    color: #94a3b8;
}

.install-done {
    color: #4ade80;
    font-size: 0.9rem;
    margin-top: 12px;
}

.install-guide[hidden] {
    display: none !important;
}

@media (min-width: 768px) {
    .install-main {
        padding-top: 40px;
    }
}