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

:root {
    --bg-primary: #0d0d12;
    --bg-secondary: #16161f;
    --bg-tertiary: #1e1e2a;
    --accent: #f2a900;
    --accent-hover: #ffc107;
    --text-primary: #ffffff;
    --text-secondary: #a0a0b0;
    --text-muted: #606070;
    --error: #e94560;
    --success: #4ade80;
    --border: #2a2a3a;
    --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    line-height: 1.6;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(13, 13, 18, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
}

.logo-icon {
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, var(--accent), #ff6b00);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
}

/* Language Menu */
.lang-menu {
    position: relative;
}

.lang-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-primary);
    cursor: pointer;
    font-size: 0.875rem;
    transition: var(--transition);
}

.lang-btn:hover {
    background: var(--bg-secondary);
    border-color: var(--accent);
}

.lang-btn svg {
    width: 16px;
    height: 16px;
    transition: var(--transition);
}

.lang-dropdown {
    position: absolute;
    top: calc(100% + 0.5rem);
    right: 0;
    min-width: 150px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 0.5rem;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: var(--transition);
}

.lang-dropdown.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.lang-option {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    border-radius: 8px;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
}

.lang-option:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.lang-option.active {
    background: var(--accent);
    color: var(--bg-primary);
}

/* Main */
.main {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 2rem 2rem;
}

/* Container */
.container {
    width: 100%;
    max-width: 440px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 2.5rem;
    box-shadow: var(--card-shadow);
}

.title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--text-primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 0.9375rem;
}

/* Form */
.form-group {
    margin-bottom: 1.25rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
}

.form-input {
    width: 100%;
    padding: 1rem 1.25rem;
    background: var(--bg-tertiary);
    border: 2px solid var(--border);
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 1rem;
    outline: none;
    transition: var(--transition);
}

.form-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 4px rgba(242, 169, 0, 0.1);
}

.form-input::placeholder {
    color: var(--text-muted);
}

/* Button */
.btn {
    width: 100%;
    padding: 1rem 1.5rem;
    background: linear-gradient(135deg, var(--accent), #e6a800);
    border: none;
    border-radius: 12px;
    color: var(--bg-primary);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    margin-top: 0.5rem;
}

.btn:hover {
    background: linear-gradient(135deg, var(--accent-hover), var(--accent));
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(242, 169, 0, 0.3);
}

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

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

/* Result */
.result {
    margin-top: 1.5rem;
    padding: 1.5rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 16px;
    display: none;
    animation: slideUp 0.4s ease;
}

.result.show {
    display: block;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-field {
    margin-bottom: 1.25rem;
}

.result-field:last-child {
    margin-bottom: 0;
}

.result-label {
    color: var(--text-muted);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
}

.result-value {
    background: var(--bg-primary);
    padding: 1rem;
    border-radius: 10px;
    word-break: break-all;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 0.8125rem;
    color: var(--accent);
    border: 1px solid var(--border);
}

.btn-copy {
    margin-top: 0.75rem;
    padding: 0.625rem 1rem;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-secondary);
    font-size: 0.8125rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.btn-copy:hover {
    background: var(--bg-secondary);
    border-color: var(--accent);
    color: var(--accent);
}

/* Alert */
.alert {
    padding: 1rem 1.25rem;
    border-radius: 12px;
    margin-top: 1rem;
    font-size: 0.875rem;
    display: none;
}

.alert.show {
    display: block;
    animation: shake 0.4s ease;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

.alert-error {
    background: rgba(233, 69, 96, 0.15);
    border: 1px solid rgba(233, 69, 96, 0.3);
    color: #ff6b7a;
}

/* Footer */
.footer {
    padding: 1.5rem 2rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.8125rem;
    border-top: 1px solid var(--border);
}

/* Responsive */
@media (max-width: 480px) {
    .header {
        padding: 1rem;
    }
    
    .container {
        padding: 1.5rem;
        border-radius: 20px;
    }
    
    .title {
        font-size: 1.5rem;
    }
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Nav */
.nav-menu {
    display: flex;
    gap: 0.5rem;
}

.nav-btn {
    padding: 0.5rem 1rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 0.8125rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.nav-btn:hover {
    background: var(--bg-secondary);
    border-color: var(--accent);
    color: var(--accent);
}

.nav-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: var(--bg-primary);
}

/* Balance */
.balance-display {
    text-align: center;
    padding: 2rem 0;
}

.balance-amount {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.balance-usd {
    color: var(--text-secondary);
    font-size: 1rem;
}

.balance-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

.balance-actions .btn {
    flex: 1;
    margin-top: 0;
}

/* Send Form */
.send-form {
    margin-top: 1rem;
}

.form-row {
    display: flex;
    gap: 1rem;
}

.form-row .form-group {
    flex: 1;
}

/* QR Code */
.qr-section {
    text-align: center;
    padding: 1.5rem 0;
}

.qr-code {
    background: white;
    padding: 1rem;
    border-radius: 12px;
    display: inline-block;
    margin: 1rem 0;
}

.container {
    animation: fadeIn 0.6s ease;
}