:root {
    --bg: #f4f5f7;
    --bg-alt: #ffffff;
    --text: #111827;
    --muted: #6b7280;
    --accent: #2563eb;
    --accent-soft: #dbeafe;
    --border: #e5e7eb;
    --danger: #dc2626;
    --radius-lg: 18px;
    --radius-md: 12px;
    --shadow-soft: 0 18px 40px rgba(15, 23, 42, 0.08);
    --transition: 0.25s ease;
    --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", sans-serif;
}

[data-theme="dark"] {
    --bg: #020617;
    --bg-alt: #020617;
    --text: #e5e7eb;
    --muted: #9ca3af;
    --accent: #38bdf8;
    --accent-soft: #0b1120;
    --border: #1f2933;
    --shadow-soft: 0 18px 40px rgba(0, 0, 0, 0.7);
}

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

body {
    margin: 0;
    padding: 0;
    font-family: var(--font-sans);
    background: radial-gradient(circle at top, #e0f2fe 0, var(--bg) 45%, var(--bg) 100%);
    color: var(--text);
    min-height: 100vh;
}

[data-theme="dark"] body {
    background: radial-gradient(circle at top, #082f49 0, #020617 45%, #020617 100%);
}

.app {
    max-width: 1180px;
    margin: 32px auto;
    padding: 0 16px 32px;
}

.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 14px;
}

.logo-circle {
    width: 40px;
    height: 40px;
    border-radius: 999px;
    background: linear-gradient(135deg, #3b82f6, #38bdf8);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #f9fafb;
    font-weight: 700;
    letter-spacing: 0.03em;
    box-shadow: 0 12px 30px rgba(37, 99, 235, 0.45);
}

.logo-text h1 {
    font-size: 1.35rem;
    margin: 0;
}

.logo-text p {
    margin: 2px 0 0;
    font-size: 0.86rem;
    color: var(--muted);
}

.theme-toggle {
    border: none;
    background: var(--bg-alt);
    color: var(--muted);
    border-radius: 999px;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-soft);
    cursor: pointer;
    transition: transform var(--transition), background var(--transition), color var(--transition);
}

.theme-toggle:hover {
    transform: translateY(-1px);
}

.app-main {
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1.1fr);
    gap: 18px;
}

@media (max-width: 900px) {
    .app-main {
        grid-template-columns: minmax(0, 1fr);
    }
}

.panel,
.output {
    background: rgba(255, 255, 255, 0.88);
    border-radius: 24px;
    padding: 20px 20px 18px;
    box-shadow: var(--shadow-soft);
    backdrop-filter: blur(18px);
    border: 1px solid rgba(148, 163, 184, 0.25);
}

[data-theme="dark"] .panel,
[data-theme="dark"] .output {
    background: rgba(15, 23, 42, 0.95);
}

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

.form-row {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.form-row label {
    font-size: 0.86rem;
    font-weight: 600;
}

.form-row input[type="text"],
.form-row input[type="url"],
.form-row select,
.form-row textarea {
    border-radius: 999px;
    border: 1px solid var(--border);
    padding: 10px 13px;
    font-size: 0.9rem;
    background: var(--bg-alt);
    color: var(--text);
    outline: none;
    transition: border var(--transition), box-shadow var(--transition), background var(--transition);
}

.form-row textarea {
    border-radius: 18px;
    resize: vertical;
    min-height: 130px;
}

.form-row input:focus,
.form-row select:focus,
.form-row textarea:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 1px var(--accent-soft);
}

.hint {
    margin: 2px 0 0;
    font-size: 0.78rem;
    color: var(--muted);
}

.checkbox-row {
    font-size: 0.86rem;
    color: var(--muted);
    display: flex;
    align-items: center;
    gap: 6px;
}

.checkbox-row input[type='checkbox'] {
    transform: scale(0.96);
}

.form-actions {
    display: flex;
    gap: 10px;
    margin-top: 10px;
}

.btn-primary,
.btn-secondary,
.btn-mini {
    border-radius: 999px;
    border: none;
    padding: 9px 16px;
    font-size: 0.86rem;
    font-weight: 600;
    cursor: pointer;
    transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, #3b82f6, #1d4ed8);
    color: #f9fafb;
    box-shadow: 0 12px 25px rgba(37, 99, 235, 0.55);
}

.btn-primary:hover {
    transform: translateY(-1px);
}

.btn-secondary {
    background: var(--bg-alt);
    color: var(--muted);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    transform: translateY(-1px);
}

.btn-mini {
    padding: 5px 10px;
    font-size: 0.78rem;
    background: var(--bg-alt);
    color: var(--muted);
    border: 1px solid var(--border);
}

.btn-mini:hover {
    transform: translateY(-1px);
}

.form-message {
    margin-top: 8px;
    font-size: 0.8rem;
    padding: 7px 10px;
    border-radius: 999px;
    border: 1px solid var(--border);
}

.form-message.error {
    border-color: var(--danger);
    color: var(--danger);
    background: #fee2e2;
}

.form-message.success {
    border-color: var(--accent);
    color: var(--accent);
    background: var(--accent-soft);
}

.output-header h2 {
    margin: 0 0 4px;
    font-size: 1.1rem;
}

.output-header p {
    margin: 0;
    font-size: 0.8rem;
    color: var(--muted);
}

.output-container {
    margin-top: 14px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.output-block {
    border-radius: 18px;
    padding: 10px 12px 9px;
    background: rgba(248, 250, 252, 0.9);
    border: 1px solid rgba(148, 163, 184, 0.3);
}

[data-theme="dark"] .output-block {
    background: rgba(15, 23, 42, 0.9);
}

.output-block-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    margin-bottom: 4px;
}

.output-block-header h3 {
    margin: 0;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--muted);
}

.output-text {
    margin: 0;
    font-size: 0.9rem;
}

.output-html {
    font-size: 0.9rem;
}

.output-html p {
    margin-top: 0.25rem;
    margin-bottom: 0.25rem;
}

.output-html h2,
.output-html h3 {
    margin: 0.4rem 0 0.2rem;
}

.output-html ul {
    margin: 0.25rem 0 0.25rem 1.1rem;
}

.loading {
    margin-top: 16px;
    padding: 10px 12px;
    border-radius: 999px;
    background: rgba(15, 23, 42, 0.03);
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.86rem;
}

.spinner {
    width: 16px;
    height: 16px;
    border-radius: 999px;
    border: 2px solid var(--accent-soft);
    border-top-color: var(--accent);
    animation: spin 0.8s linear infinite;
}

.app-footer {
    margin-top: 18px;
    text-align: center;
    font-size: 0.78rem;
    color: var(--muted);
}

.hidden {
    display: none !important;
}

.mode-field.hidden {
    display: none !important;
}

.output-block-actions {
    display: flex;
    gap: 6px;
    align-items: center;
}

textarea.hidden {
    display: none;
}

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