/* ============================================
   TOML/YAML/JSON Converter — Styles
   Theme: Dark with gradient accents
   ============================================ */

:root {
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'SF Mono', monospace;

    --bg: #0C1222;
    --bg-card: #141D30;
    --bg-input: #0C1222;
    --bg-hover: #1A2842;

    --border: rgba(99, 102, 241, 0.12);
    --border-hover: rgba(99, 102, 241, 0.28);
    --border-focus: #6366F1;

    --text: #E2E8F0;
    --text-secondary: #94A3B8;
    --text-muted: #475569;

    --primary: #6366F1;
    --primary-glow: rgba(99, 102, 241, 0.2);
    --secondary: #818CF8;
    --green: #34D399;
    --red: #F87171;

    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 2px 16px rgba(0, 0, 0, 0.4);
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
    font-family: var(--font-sans);
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

.app {
    max-width: 960px;
    margin: 0 auto;
    padding: 24px 16px 40px;
}

.header {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-bottom: 24px;
}

.header-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius);
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    box-shadow: 0 0 20px var(--primary-glow);
}

.header-title {
    font-size: 1.3rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.header-sub {
    font-size: 0.82rem;
    color: var(--text-secondary);
}

/* Converter Layout */
.converter-layout {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 12px;
    align-items: stretch;
}

.panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 16px;
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    animation: fadeIn 0.35s ease-out;
}

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

.format-select {
    padding: 7px 12px;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--primary);
    font-family: var(--font-sans);
    font-size: 0.85rem;
    font-weight: 700;
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.format-select option {
    background: var(--bg-card);
    text-transform: none;
}

.format-select:focus {
    outline: none;
    border-color: var(--primary);
}

.panel-actions {
    display: flex;
    gap: 4px;
}

.btn-sm {
    padding: 5px 10px;
    background: transparent;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-size: 0.72rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition);
}

.btn-sm:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.code-area {
    flex: 1;
    min-height: 400px;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 14px;
    font-family: var(--font-mono);
    font-size: 0.82rem;
    color: var(--text);
    resize: none;
    line-height: 1.6;
    tab-size: 2;
    transition: border-color var(--transition);
}

.code-area:focus {
    outline: none;
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px var(--primary-glow);
}

.code-area::placeholder {
    color: var(--text-muted);
}

.output-area {
    color: var(--green);
    background: rgba(52, 211, 153, 0.03);
}

.validation-msg {
    margin-top: 6px;
    font-size: 0.75rem;
    min-height: 20px;
}

.validation-msg.valid {
    color: var(--green);
}

.validation-msg.error {
    color: var(--red);
}

/* Convert Controls */
.convert-controls {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.btn-convert {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border: none;
    color: #fff;
    font-size: 1.4rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 12px var(--primary-glow);
    transition: all var(--transition);
}

.btn-convert:hover {
    transform: scale(1.08);
    box-shadow: 0 4px 20px var(--primary-glow);
}

.btn-swap {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    font-size: 1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
}

.btn-swap:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.shortcuts-hint {
    text-align: center;
    margin-top: 14px;
    font-size: 0.72rem;
    color: var(--text-muted);
}

.shortcuts-hint kbd {
    padding: 2px 6px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.68rem;
}

.footer {
    text-align: center;
    margin-top: 16px;
    font-size: 0.75rem;
    color: var(--text-muted);
}

.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(80px);
    background: var(--bg-card);
    border: 1px solid var(--green);
    border-radius: var(--radius-sm);
    padding: 10px 20px;
    font-size: 0.82rem;
    color: var(--green);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
    opacity: 0;
    transition: transform 0.3s ease, opacity 0.3s ease;
    pointer-events: none;
    z-index: 100;
}

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

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(8px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 700px) {
    .converter-layout {
        grid-template-columns: 1fr;
    }

    .convert-controls {
        flex-direction: row;
        padding: 6px 0;
    }

    .code-area {
        min-height: 200px;
    }
}