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

:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: #16161f;
    --accent-cyan: #00f0ff;
    --accent-purple: #b347ff;
    --accent-pink: #ff2d7a;
    --text-primary: #e4e4e7;
    --text-secondary: #71717a;
    --border-color: rgba(255, 255, 255, 0.06);
}

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    position: relative;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(ellipse 80% 50% at 50% -20%, rgba(0, 240, 255, 0.08), transparent),
        radial-gradient(ellipse 60% 40% at 100% 100%, rgba(179, 71, 255, 0.06), transparent);
    pointer-events: none;
}

body::after {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    pointer-events: none;
}

.container {
    background: var(--bg-secondary);
    border-radius: 20px;
    border: 1px solid var(--border-color);
    padding: 48px 40px;
    max-width: 460px;
    width: 100%;
    position: relative;
    z-index: 1;
}

.container::before {
    content: '';
    position: absolute;
    top: -1px;
    left: 40px;
    right: 40px;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent-cyan), transparent);
    opacity: 0.6;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

.avatar{
    width: 72px;
    height: 72px;
    background: var(--bg-card);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: 700;
    color: var(--accent-cyan);
    margin: 0 auto 20px;
    position: relative;
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: inherit;
}

.avatar::after {
    content: '';
    position: absolute;
    inset: -2px;
    border-radius: 18px;
    background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
    z-index: -1;
    opacity: 0.4;
    filter: blur(8px);
}

h1 {
    color: var(--text-primary);
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.tagline {
    color: var(--text-secondary);
    font-size: 14px;
    margin-top: 6px;
}

.payment-tabs {
    display: flex;
    background: var(--bg-card);
    border-radius: 12px;
    padding: 4px;
    margin-bottom: 28px;
    border: 1px solid var(--border-color);
}

.tab-btn {
    flex: 1;
    padding: 14px 20px;
    border: none;
    border-radius: 10px;
    background: transparent;
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.25s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-family: 'Inter', sans-serif;
}

.tab-btn:hover {
    color: var(--text-primary);
}

.tab-btn.active {
    background: var(--bg-secondary);
    color: var(--accent-cyan);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.tab-icon {
    font-size: 18px;
}

.payment-section {
    display: none;
}

.payment-section.active {
    display: block;
    animation: slideUp 0.35s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.payment-section h2 {
    color: var(--text-primary);
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.instruction {
    color: var(--text-secondary);
    font-size: 13px;
    margin-bottom: 24px;
}

.qr-container {
    background: #ffffff;
    border-radius: 16px;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    max-width: 220px;
    margin: 0 auto;
    position: relative;
}

.qr-container::before {
    content: '';
    position: absolute;
    inset: -1px;
    border-radius: 17px;
    background: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-purple) 100%);
    z-index: -1;
}

.qr-code {
    width: 100%;
    max-width: 180px;
    height: auto;
    border-radius: 4px;
}

.crypto-tabs {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    margin-bottom: 20px;
}

.crypto-btn {
    padding: 12px 8px;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    background: var(--bg-card);
    color: var(--text-secondary);
    font-size: 11px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    font-family: 'Inter', sans-serif;
}

.crypto-btn img {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    filter: grayscale(0.3);
    transition: filter 0.2s ease;
}

.crypto-btn:hover {
    border-color: rgba(255, 255, 255, 0.12);
    color: var(--text-primary);
}

.crypto-btn:hover img {
    filter: grayscale(0);
}

.crypto-btn.active {
    border-color: var(--accent-cyan);
    background: rgba(0, 240, 255, 0.05);
    color: var(--accent-cyan);
}

.crypto-btn.active img {
    filter: grayscale(0);
}

.address-container {
    margin-top: 16px;
}

.address-box {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 14px 16px;
    display: flex;
    align-items: center;
    gap: 14px;
    border: 1px solid var(--border-color);
}

.address {
    flex: 1;
    color: var(--text-secondary);
    font-size: 11px;
    font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
    word-break: break-all;
    line-height: 1.6;
    letter-spacing: 0.02em;
}

.copy-btn {
    padding: 10px 18px;
    border: none;
    border-radius: 8px;
    background: var(--accent-cyan);
    color: var(--bg-primary);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
    font-family: 'Inter', sans-serif;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.copy-btn:hover {
    background: #00d4e0;
    box-shadow: 0 0 20px rgba(0, 240, 255, 0.3);
}

.copy-btn:active {
    transform: scale(0.96);
}

footer {
    margin-top: 36px;
    text-align: center;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

footer p {
    color: var(--text-secondary);
    font-size: 13px;
}

.toast {
    position: fixed;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    background: var(--bg-card);
    color: var(--accent-cyan);
    padding: 14px 28px;
    border-radius: 10px;
    font-weight: 500;
    font-size: 13px;
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1000;
    border: 1px solid var(--accent-cyan);
    box-shadow: 0 0 30px rgba(0, 240, 255, 0.15);
    pointer-events: none;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

@media (max-width: 480px) {
    .container {
        padding: 32px 24px;
        border-radius: 16px;
    }

    h1 {
        font-size: 20px;
    }

    .avatar {
        width: 64px;
        height: 64px;
        font-size: 20px;
        border-radius: 14px;
    }

    .tab-btn {
        padding: 12px 14px;
        font-size: 13px;
    }

    .crypto-tabs {
        grid-template-columns: repeat(2, 1fr);
    }

    .crypto-btn {
        padding: 10px 6px;
        font-size: 10px;
    }

    .crypto-btn img {
        width: 22px;
        height: 22px;
    }

    .address {
        font-size: 10px;
    }

    .copy-btn {
        padding: 8px 14px;
        font-size: 11px;
    }

    .qr-container {
        padding: 16px;
        max-width: 200px;
    }
}

@media (max-width: 360px) {
    .crypto-tabs {
        grid-template-columns: repeat(2, 1fr);
        gap: 6px;
    }
    
    .address-box {
        flex-direction: column;
        gap: 12px;
    }
    
    .copy-btn {
        width: 100%;
    }
}