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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--tg-theme-bg-color, #ffffff);
    color: var(--tg-theme-text-color, #000000);
    min-height: 100vh;
    padding: 0;
    margin: 0;
}

.app-container {
    min-height: calc(100vh - 70px);
    padding-bottom: 20px;
}

/* ========== SCREENS ========== */
.screen {
    min-height: calc(100vh - 70px);
    padding: 20px;
    max-width: 600px;
    margin: 0 auto;
}

.screen-header {
    margin-bottom: 24px;
    position: relative;
}

.screen-header h1 {
    font-size: 28px;
    font-weight: 700;
    color: var(--tg-theme-text-color, #000000);
    text-align: center;
}

.back-button {
    position: absolute;
    left: 0;
    top: 0;
    background: transparent;
    border: none;
    color: var(--tg-theme-button-color, #3390ec);
    font-size: 16px;
    cursor: pointer;
    padding: 8px 0;
    display: flex;
    align-items: center;
    gap: 4px;
}

.back-button:active {
    opacity: 0.7;
}

.content {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* ========== WELCOME SCREEN ========== */
.welcome-screen {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 20px;
}

.welcome-container {
    text-align: center;
    width: 100%;
    max-width: 400px;
}

.welcome-avatar {
    margin-bottom: 24px;
}

.avatar-img {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    border: 4px solid var(--tg-theme-button-color, #3390ec);
    object-fit: cover;
}

.avatar-placeholder {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: var(--tg-theme-button-color, #3390ec);
    color: var(--tg-theme-button-text-color, #ffffff);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    font-weight: 700;
    margin: 0 auto;
}

.welcome-title {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--tg-theme-text-color, #000000);
}

.welcome-name {
    font-size: 18px;
    color: var(--tg-theme-hint-color, #999999);
    margin-bottom: 32px;
}

.welcome-buttons {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.btn-primary {
    width: 100%;
    padding: 16px 24px;
    background: var(--tg-theme-button-color, #3390ec);
    color: var(--tg-theme-button-text-color, #ffffff);
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s;
}

.btn-primary:active {
    opacity: 0.8;
}

.btn-secondary {
    width: 100%;
    padding: 16px 24px;
    background: var(--tg-theme-secondary-bg-color, #f1f1f1);
    color: var(--tg-theme-text-color, #000000);
    border: 2px solid var(--tg-theme-button-color, #3390ec);
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s;
}

.btn-secondary:active {
    opacity: 0.8;
}

/* ========== SHOWCASE SCREEN ========== */
.showcase-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 16px;
    margin-top: 16px;
}

.module-card {
    background: var(--tg-theme-secondary-bg-color, #f1f1f1);
    border-radius: 16px;
    padding: 20px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.module-card:active {
    transform: scale(0.98);
}

.module-icon {
    font-size: 48px;
    margin-bottom: 8px;
}

.module-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--tg-theme-text-color, #000000);
    margin: 0;
}

.btn-demo {
    width: 100%;
    padding: 10px 16px;
    background: var(--tg-theme-button-color, #3390ec);
    color: var(--tg-theme-button-text-color, #ffffff);
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s;
    margin-top: auto;
}

.btn-demo:active {
    opacity: 0.8;
}

/* ========== INFO CARDS ========== */
.info-card {
    background: var(--tg-theme-secondary-bg-color, #f1f1f1);
    border-radius: 16px;
    padding: 24px;
    text-align: center;
}

.info-card h2 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--tg-theme-text-color, #000000);
}

.info-card p {
    font-size: 14px;
    color: var(--tg-theme-hint-color, #666666);
    line-height: 1.6;
}

.stub-card {
    padding: 40px 24px;
}

.stub-icon {
    font-size: 64px;
    margin-bottom: 16px;
}

.stub-route {
    margin-top: 16px;
    padding-top: 16px;
    border-top: 1px solid var(--tg-theme-hint-color, #e0e0e0);
    font-size: 12px;
    color: var(--tg-theme-hint-color, #999999);
}

/* ========== BOTTOM NAVIGATION ========== */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--tg-theme-secondary-bg-color, #f1f1f1);
    border-top: 1px solid var(--tg-theme-hint-color, #e0e0e0);
    display: flex;
    justify-content: space-around;
    align-items: center;
    padding: 8px 0;
    z-index: 1000;
    max-width: 600px;
    margin: 0 auto;
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.1);
}

.nav-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 8px;
    text-decoration: none;
    color: var(--tg-theme-hint-color, #999999);
    transition: color 0.2s;
    cursor: pointer;
}

.nav-item.active {
    color: var(--tg-theme-button-color, #3390ec);
}

.nav-icon {
    font-size: 24px;
    margin-bottom: 4px;
}

.nav-label {
    font-size: 12px;
    font-weight: 500;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 480px) {
    .screen {
        padding: 16px;
    }
    
    .screen-header h1 {
        font-size: 24px;
    }
    
    .welcome-title {
        font-size: 28px;
    }
    
    .avatar-img,
    .avatar-placeholder {
        width: 100px;
        height: 100px;
    }
    
    .avatar-placeholder {
        font-size: 40px;
    }
    
    .showcase-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }
    
    .module-card {
        padding: 16px;
    }
    
    .module-icon {
        font-size: 40px;
    }
    
    .module-name {
        font-size: 14px;
    }
    
    .bottom-nav {
        padding: 6px 0;
    }
    
    .nav-icon {
        font-size: 22px;
    }
    
    .nav-label {
        font-size: 11px;
    }
}