:root {
    /* Telegram theme colors (fallbacks) */
    --tg-theme-bg-color: #1a1a2e;
    --tg-theme-text-color: #ffffff;
    --tg-theme-hint-color: #94a3b8;
    --tg-theme-link-color: #00d4ff;
    --tg-theme-button-color: #7c3aed;
    --tg-theme-button-text-color: #ffffff;
    --tg-theme-secondary-bg-color: #16213e;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--tg-theme-bg-color);
    min-height: 100vh;
    color: var(--tg-theme-text-color);
    padding: 16px;
    padding-bottom: 100px; /* Space for Telegram MainButton */
}

.container {
    max-width: 600px;
    margin: 0 auto;
    width: 100%;
}

@media (min-width: 640px) {
    .container {
        max-width: 100%;
    }
    body {
        max-width: 900px;
        margin: 0 auto;
    }
}

header {
    text-align: center;
    margin-bottom: 24px;
}

header h1 {
    font-size: 1.5rem;
    margin-bottom: 6px;
    background: linear-gradient(90deg, var(--tg-theme-link-color), var(--tg-theme-button-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

header p {
    color: var(--tg-theme-hint-color);
    font-size: 0.9rem;
}

.user-greeting {
    text-align: center;
    margin-bottom: 20px;
    padding: 12px;
    background: var(--tg-theme-secondary-bg-color);
    border-radius: 12px;
    font-size: 0.9rem;
    color: var(--tg-theme-hint-color);
}

.user-greeting strong {
    color: var(--tg-theme-text-color);
}

.currency-display {
    background: var(--tg-theme-secondary-bg-color);
    border-radius: 12px;
    padding: 14px 16px;
    margin-bottom: 20px;
}

.rates-grid {
    display: flex;
    gap: 16px;
    margin-bottom: 10px;
}

.rate-item {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.rate-item .rate-currency {
    font-size: 0.72rem;
    color: var(--tg-theme-hint-color);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

.rate-item .rate-value {
    font-size: 1rem;
    font-weight: 600;
    color: var(--tg-theme-link-color);
}

.rate-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.rate-footer .rate-meta {
    font-size: 0.75rem;
    color: var(--tg-theme-hint-color);
}

.btn-refresh {
    padding: 8px 14px;
    border: none;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.1);
    color: var(--tg-theme-hint-color);
    cursor: pointer;
    font-size: 0.85rem;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 6px;
}

.btn-refresh:active {
    transform: scale(0.95);
}

.btn-refresh.loading .refresh-icon {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.manual-rate-section {
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.manual-rate-toggle {
    display: flex;
    align-items: center;
    gap: 10px;
}

.toggle-switch {
    position: relative;
    width: 44px;
    height: 24px;
}

.toggle-switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.toggle-slider {
    position: absolute;
    cursor: pointer;
    inset: 0;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 24px;
    transition: 0.3s;
}

.toggle-slider:before {
    position: absolute;
    content: "";
    height: 18px;
    width: 18px;
    left: 3px;
    bottom: 3px;
    background: white;
    border-radius: 50%;
    transition: 0.3s;
}

.toggle-switch input:checked + .toggle-slider {
    background: var(--tg-theme-button-color);
}

.toggle-switch input:checked + .toggle-slider:before {
    transform: translateX(20px);
}

.manual-rate-toggle label {
    color: var(--tg-theme-hint-color);
    font-size: 0.85rem;
}

.manual-rate-input {
    display: none;
    margin-top: 12px;
}

.manual-rate-input.visible {
    display: flex;
    align-items: center;
    gap: 10px;
}

.manual-rate-input input {
    width: 100px;
    padding: 10px 12px;
    border: none;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.1);
    color: var(--tg-theme-text-color);
    font-size: 1rem;
}

.manual-rate-input span {
    color: var(--tg-theme-hint-color);
    font-size: 0.85rem;
}

.tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
}

.tab-btn {
    flex: 1;
    padding: 12px 16px;
    border: none;
    border-radius: 10px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    background: var(--tg-theme-secondary-bg-color);
    color: var(--tg-theme-hint-color);
}

.tab-btn:active {
    transform: scale(0.98);
}

.tab-btn.active {
    background: var(--tg-theme-button-color);
    color: var(--tg-theme-button-text-color);
}

.form-container {
    background: var(--tg-theme-secondary-bg-color);
    border-radius: 16px;
    padding: 20px;
}

.form-section {
    display: none;
}

.form-section.active {
    display: block;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--tg-theme-hint-color);
    font-size: 0.85rem;
}

.form-group input {
    width: 100%;
    padding: 14px 16px;
    border: none;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.08);
    color: var(--tg-theme-text-color);
    font-size: 1rem;
    transition: all 0.2s ease;
}

.form-group input:focus {
    outline: none;
    background: rgba(255, 255, 255, 0.12);
}

.form-group input::placeholder {
    color: var(--tg-theme-hint-color);
    opacity: 0.6;
}

.radio-group {
    display: flex;
    gap: 10px;
}

.radio-option {
    flex: 1;
}

.radio-option input {
    display: none;
}

.radio-option label {
    display: block;
    padding: 12px 14px;
    border-radius: 10px;
    cursor: pointer;
    text-align: center;
    transition: all 0.2s ease;
    color: var(--tg-theme-text-color);
    font-size: 0.9rem;
    background: rgba(255, 255, 255, 0.08);
}

.radio-option input:checked + label {
    background: var(--tg-theme-button-color);
    color: var(--tg-theme-button-text-color);
}

.radio-option label:active {
    transform: scale(0.98);
}

.freight-japan-input {
    display: none;
    margin-top: 12px;
}

.freight-japan-input.visible {
    display: block;
}

.btn-calculate {
    width: 100%;
    padding: 14px;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    background: var(--tg-theme-button-color);
    color: var(--tg-theme-button-text-color);
    margin-top: 8px;
    transition: all 0.2s ease;
}

.btn-calculate:active {
    transform: scale(0.98);
}

.result-container {
    display: none;
    margin-top: 20px;
    background: var(--tg-theme-secondary-bg-color);
    border-radius: 16px;
    padding: 20px;
}

.result-container.visible {
    display: block;
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.result-header h2 {
    font-size: 1.1rem;
    color: var(--tg-theme-link-color);
}

.result-date {
    color: var(--tg-theme-hint-color);
    font-size: 0.85rem;
}

.result-section {
    margin-bottom: 20px;
}

.result-section h3 {
    font-size: 0.9rem;
    color: var(--tg-theme-button-color);
    margin-bottom: 12px;
}

.result-row {
    display: flex;
    justify-content: space-between;
    padding: 8px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    font-size: 0.9rem;
}

.result-row:last-child {
    border-bottom: none;
}

.result-row--highlight {
    background: rgba(0, 212, 255, 0.1);
    margin: -8px;
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 0;
}

.result-row .label {
    color: var(--tg-theme-hint-color);
}

.result-row .value {
    font-weight: 600;
    color: var(--tg-theme-text-color);
}

.result-total {
    background: rgba(124, 58, 237, 0.15);
    border-radius: 12px;
    padding: 16px;
    margin-top: 16px;
}

.result-total .result-row .value {
    color: var(--tg-theme-link-color);
}

.final-amount {
    background: linear-gradient(135deg, rgba(0, 212, 255, 0.15), rgba(124, 58, 237, 0.15));
    border-radius: 12px;
    padding: 16px;
    margin-top: 16px;
    text-align: center;
}

.final-amount .label {
    color: var(--tg-theme-hint-color);
    margin-bottom: 8px;
    font-size: 0.9rem;
}

.final-amount .value {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--tg-theme-link-color);
}

.action-buttons {
    display: flex;
    gap: 10px;
    margin-top: 16px;
}

.btn-action {
    flex: 1;
    padding: 12px;
    border: none;
    border-radius: 10px;
    font-size: 0.9rem;
    cursor: pointer;
    background: rgba(255, 255, 255, 0.1);
    color: var(--tg-theme-hint-color);
    transition: all 0.2s ease;
}

.btn-action:active {
    transform: scale(0.98);
}

.btn-action.primary {
    background: var(--tg-theme-button-color);
    color: var(--tg-theme-button-text-color);
}

.fixed-costs-info {
    margin-top: 24px;
    padding: 16px;
    background: var(--tg-theme-secondary-bg-color);
    border-radius: 12px;
    opacity: 0.7;
}

.fixed-costs-info h3 {
    font-size: 0.8rem;
    color: var(--tg-theme-hint-color);
    margin-bottom: 12px;
}

.fixed-costs-info .cost-item {
    display: flex;
    justify-content: space-between;
    padding: 6px 0;
    font-size: 0.8rem;
    color: var(--tg-theme-hint-color);
}

.error-message {
    background: rgba(239, 68, 68, 0.2);
    border-radius: 10px;
    padding: 12px 16px;
    color: #fca5a5;
    margin-bottom: 16px;
    display: none;
    font-size: 0.9rem;
}

.error-message.visible {
    display: block;
}

.toast {
    position: fixed;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--tg-theme-text-color);
    color: var(--tg-theme-bg-color);
    padding: 12px 24px;
    border-radius: 10px;
    font-size: 0.9rem;
    font-weight: 500;
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 1000;
}

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