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

:root {
    --color-bg: #ffffff;
    --color-bg-secondary: #f8fafc;
    --color-bg-tertiary: #f1f5f9;
    --color-dark: #0f172a;
    --color-text: #1e293b;
    --color-text-secondary: #64748b;
    --color-text-muted: #94a3b8;
    --color-accent: #2563eb;
    --color-accent-hover: #1d4ed8;
    --color-accent-light: #eff6ff;
    --color-success: #059669;
    --color-success-light: #ecfdf5;
    --color-error: #dc2626;
    --color-error-light: #fef2f2;
    --color-warning: #d97706;
    --color-warning-light: #fffbeb;
    --color-border: #e2e8f0;
    --color-border-focus: #2563eb;
    --color-card: #ffffff;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.06), 0 2px 4px -2px rgba(0, 0, 0, 0.04);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.06), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --transition: 0.2s ease;
    --max-width: 1280px;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

/* ========== HEADER ========== */
.site-header {
    background: var(--color-dark);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header-brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.brand-icon {
    flex-shrink: 0;
}

.brand-text {
    font-size: 1.125rem;
    font-weight: 600;
    color: #ffffff;
    letter-spacing: -0.02em;
}

.header-nav {
    display: flex;
    align-items: center;
    gap: 1rem;
}

/* Language Selector */
.lang-selector {
    position: relative;
}

.lang-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: var(--radius-sm);
    color: #e2e8f0;
    font-size: 0.8125rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition);
    font-family: inherit;
}

.lang-btn:hover {
    background: rgba(255, 255, 255, 0.14);
    border-color: rgba(255, 255, 255, 0.2);
}

.lang-dropdown {
    position: absolute;
    top: calc(100% + 6px);
    right: 0;
    min-width: 180px;
    background: var(--color-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-4px);
    transition: all var(--transition);
    z-index: 200;
    overflow: hidden;
}

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

.lang-option {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 16px;
    font-size: 0.875rem;
    color: var(--color-text);
    cursor: pointer;
    transition: background var(--transition);
    border: none;
    background: none;
    width: 100%;
    font-family: inherit;
    text-align: left;
}

.lang-option:hover {
    background: var(--color-bg-secondary);
}

.lang-option.active {
    color: var(--color-accent);
    font-weight: 500;
}

.lang-option .native-name {
    color: var(--color-text-secondary);
    font-size: 0.8125rem;
}

/* ========== HERO ========== */
.hero-section {
    background: linear-gradient(135deg, var(--color-dark) 0%, #1e3a5f 100%);
    padding: 4rem 2rem;
    text-align: center;
}

.hero-content {
    max-width: var(--max-width);
    margin: 0 auto;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: -0.03em;
    margin-bottom: 0.75rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: #94a3b8;
    font-weight: 400;
    max-width: 480px;
    margin: 0 auto;
}

/* ========== MAIN SECTION ========== */
.main-section {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 3rem 2rem;
    flex: 1;
}

.main-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
    align-items: start;
}

/* ========== INSTRUCTIONS PANEL ========== */
.instructions-panel {
    position: sticky;
    top: 96px;
}

.instructions-card {
    background: var(--color-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 2rem;
    box-shadow: var(--shadow-sm);
}

.section-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--color-dark);
    letter-spacing: -0.02em;
    margin-bottom: 1.5rem;
}

.step-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.step {
    display: flex;
    gap: 1rem;
}

.step-number {
    flex-shrink: 0;
    width: 36px;
    height: 36px;
    background: var(--color-accent-light);
    color: var(--color-accent);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.875rem;
    font-weight: 600;
}

.step-content h3 {
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--color-dark);
    margin-bottom: 0.25rem;
}

.step-content p {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    line-height: 1.5;
}

.info-box {
    display: flex;
    gap: 0.75rem;
    padding: 1rem;
    background: var(--color-accent-light);
    border: 1px solid rgba(37, 99, 235, 0.1);
    border-radius: var(--radius-sm);
}

.info-icon {
    flex-shrink: 0;
    color: var(--color-accent);
    margin-top: 2px;
}

.info-title {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--color-dark);
    margin-bottom: 0.25rem;
}

.info-text {
    font-size: 0.8125rem;
    color: var(--color-text-secondary);
    line-height: 1.5;
}

/* ========== FORM PANEL ========== */
.form-panel {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-card {
    background: var(--color-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 2rem;
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--transition);
}

.form-card:hover {
    box-shadow: var(--shadow-md);
}

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

.form-group:last-child {
    margin-bottom: 0;
}

.form-label {
    display: block;
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--color-text);
    margin-bottom: 0.5rem;
    letter-spacing: 0.01em;
}

.form-input {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 0.9375rem;
    font-family: inherit;
    color: var(--color-text);
    background: var(--color-bg);
    transition: all var(--transition);
    outline: none;
}

.form-input:focus {
    border-color: var(--color-border-focus);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

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

.form-textarea {
    width: 100%;
    padding: 12px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-family: 'Cascadia Code', 'Fira Code', 'JetBrains Mono', monospace;
    color: var(--color-text);
    background: var(--color-bg);
    transition: all var(--transition);
    outline: none;
    resize: vertical;
    min-height: 140px;
    line-height: 1.5;
}

.form-textarea:focus {
    border-color: var(--color-border-focus);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-textarea::placeholder {
    color: var(--color-text-muted);
    font-family: inherit;
}

.input-with-action {
    display: flex;
    gap: 0.75rem;
}

.input-with-action .form-input {
    flex: 1;
}

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

.flex-1 {
    flex: 1;
}

/* ========== TOGGLE SWITCH ========== */
.toggle-label {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    font-size: 0.875rem;
    color: var(--color-text);
    user-select: none;
    white-space: nowrap;
    height: 42px;
}

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

.toggle-switch {
    position: relative;
    width: 40px;
    height: 22px;
    background: var(--color-border);
    border-radius: 11px;
    transition: background var(--transition);
    flex-shrink: 0;
}

.toggle-switch::after {
    content: '';
    position: absolute;
    top: 3px;
    left: 3px;
    width: 16px;
    height: 16px;
    background: white;
    border-radius: 50%;
    transition: transform var(--transition);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15);
}

.toggle-input:checked + .toggle-switch {
    background: var(--color-accent);
}

.toggle-input:checked + .toggle-switch::after {
    transform: translateX(18px);
}

/* ========== BUTTONS ========== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 10px 20px;
    font-size: 0.875rem;
    font-weight: 500;
    font-family: inherit;
    border-radius: var(--radius-sm);
    border: 1px solid transparent;
    cursor: pointer;
    transition: all var(--transition);
    outline: none;
    text-decoration: none;
    white-space: nowrap;
}

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

.btn-primary {
    background: var(--color-accent);
    color: #ffffff;
    border-color: var(--color-accent);
}

.btn-primary:hover:not(:disabled) {
    background: var(--color-accent-hover);
    border-color: var(--color-accent-hover);
}

.btn-secondary {
    background: var(--color-bg);
    color: var(--color-text);
    border-color: var(--color-border);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--color-bg-secondary);
    border-color: #cbd5e1;
}

.btn-ghost {
    background: transparent;
    color: var(--color-text-secondary);
    border-color: transparent;
}

.btn-ghost:hover:not(:disabled) {
    background: var(--color-bg-secondary);
    color: var(--color-text);
}

.btn-full {
    width: 100%;
}

/* ========== STATUS MESSAGES ========== */
.status-message {
    margin-top: 0.75rem;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-sm);
    font-size: 0.8125rem;
    line-height: 1.5;
    display: flex;
    align-items: start;
    gap: 0.5rem;
}

.status-message.success {
    background: var(--color-success-light);
    color: var(--color-success);
    border: 1px solid rgba(5, 150, 105, 0.15);
}

.status-message.error {
    background: var(--color-error-light);
    color: var(--color-error);
    border: 1px solid rgba(220, 38, 38, 0.15);
}

.status-message.warning {
    background: var(--color-warning-light);
    color: var(--color-warning);
    border: 1px solid rgba(217, 119, 6, 0.15);
}

.status-message.info {
    background: var(--color-accent-light);
    color: var(--color-accent);
    border: 1px solid rgba(37, 99, 235, 0.1);
}

.validation-hint {
    margin-top: 0.5rem;
    font-size: 0.8125rem;
}

.validation-hint.valid {
    color: var(--color-success);
}

.validation-hint.invalid {
    color: var(--color-error);
}

/* ========== RESULT SECTION ========== */
.result-content {
    margin-bottom: 1.5rem;
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--color-border);
    font-size: 0.875rem;
}

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

.result-label {
    color: var(--color-text-secondary);
    font-weight: 400;
}

.result-value {
    color: var(--color-text);
    font-weight: 500;
    text-align: right;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}

.status-badge.processing,
.status-badge.pending,
.status-badge.submitted {
    background: var(--color-warning-light);
    color: var(--color-warning);
}

.status-badge.completed {
    background: var(--color-success-light);
    color: var(--color-success);
}

.status-badge.failed {
    background: var(--color-error-light);
    color: var(--color-error);
}

.status-badge.available {
    background: var(--color-accent-light);
    color: var(--color-accent);
}

.status-badge::before {
    content: '';
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: currentColor;
}

/* ========== LOADING SPINNER ========== */
.spinner {
    display: inline-block;
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: #ffffff;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

.spinner.dark {
    border-color: rgba(0, 0, 0, 0.1);
    border-top-color: var(--color-accent);
}

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

/* ========== ERROR PAGE ========== */
.error-section {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 60vh;
    padding: 2rem;
    text-align: center;
}

.error-title {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-dark);
    margin-bottom: 0.75rem;
}

.error-text {
    color: var(--color-text-secondary);
    margin-bottom: 2rem;
}

/* ========== FOOTER ========== */
.site-footer {
    background: var(--color-dark);
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    margin-top: auto;
}

.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 1.5rem 2rem;
    text-align: center;
    font-size: 0.8125rem;
    color: #64748b;
}

/* ========== HIDDEN UTILITY ========== */
.hidden {
    display: none !important;
}

/* ========== PULSE ANIMATION for processing ========== */
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

.pulse {
    animation: pulse 2s ease-in-out infinite;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 900px) {
    .main-grid {
        grid-template-columns: 1fr;
    }

    .instructions-panel {
        position: static;
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .hero-section {
        padding: 2.5rem 1.5rem;
    }

    .main-section {
        padding: 2rem 1rem;
    }

    .form-row {
        flex-direction: column;
    }
}

@media (max-width: 600px) {
    .header-inner {
        padding: 0 1rem;
    }

    .hero-title {
        font-size: 1.5rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .instructions-card,
    .form-card {
        padding: 1.25rem;
    }

    .input-with-action {
        flex-direction: column;
    }
}