:root {
    --bg-color: #0b0f19;
    --surface-color: #131a2a;
    --surface-hover: #1e293b;
    --border-color: #1e293b;
    --border-light: rgba(255, 255, 255, 0.05);

    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-tertiary: #64748b;

    --color-1xx: #94a3b8;
    --color-1xx-bg: rgba(148, 163, 184, 0.1);

    --color-2xx: #10b981;
    --color-2xx-bg: rgba(16, 185, 129, 0.1);

    --color-3xx: #3b82f6;
    --color-3xx-bg: rgba(59, 130, 246, 0.1);

    --color-4xx: #f59e0b;
    --color-4xx-bg: rgba(245, 158, 11, 0.1);

    --color-5xx: #ef4444;
    --color-5xx-bg: rgba(239, 68, 68, 0.1);

    --font-ui: 'Inter', system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-ui);
    line-height: 1.6;
    height: 100vh;
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
}

.hidden {
    display: none !important;
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-width: 1400px;
    margin: 0 auto;
}

/* Header & Search */
.search-header {
    padding: 1.5rem 2rem;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-color);
    position: relative;
    z-index: 10;
}

.search-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    max-width: 800px;
    margin: 0 auto;
}

.search-icon {
    position: absolute;
    left: 1.5rem;
    color: var(--text-tertiary);
}

#search-input {
    width: 100%;
    padding: 1.25rem 1.25rem 1.25rem 3.5rem;
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-primary);
    font-family: var(--font-ui);
    font-size: 1.1rem;
    outline: none;
    transition: all 0.2s;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

#search-input:focus {
    border-color: rgba(255, 255, 255, 0.2);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.4);
}

#search-input::placeholder {
    color: var(--text-tertiary);
}

.keyboard-hint {
    position: absolute;
    right: 1.5rem;
    color: var(--text-tertiary);
    font-size: 0.8rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    pointer-events: none;
}

.keyboard-hint span {
    display: inline-block;
    background: var(--border-color);
    padding: 0.1rem 0.4rem;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Main Content Split */
.main-content {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* Sidebar List */
.status-list-container {
    width: 350px;
    border-right: 1px solid var(--border-color);
    overflow-y: auto;
    background: var(--surface-color);
}

.status-list {
    list-style: none;
    padding: 1rem;
}

.status-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.1s;
    margin-bottom: 0.25rem;
    border: 1px solid transparent;
}

.status-item:hover {
    background: var(--surface-hover);
}

.status-item.active {
    background: var(--border-color);
    border-color: var(--border-light);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.status-item .code-badge {
    font-family: var(--font-mono);
    font-weight: 700;
    font-size: 1.1rem;
    padding: 0.25rem 0.5rem;
    border-radius: 6px;
    min-width: 55px;
    text-align: center;
}

.status-item .phrase {
    font-weight: 500;
    font-size: 0.95rem;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Detail Panel */
.detail-panel {
    flex: 1;
    overflow-y: auto;
    padding: 3rem 4rem;
    background: var(--bg-color);
    position: relative;
}

.empty-state {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    color: var(--text-tertiary);
}

.empty-state svg {
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state h2 {
    color: var(--text-secondary);
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.detail-content {
    max-width: 800px;
    margin: 0 auto;
    animation: fadeIn 0.2s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

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

.detail-header {
    margin-bottom: 3rem;
    display: flex;
    align-items: baseline;
    gap: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.detail-header h1 {
    font-family: var(--font-mono);
    font-size: 5rem;
    font-weight: 800;
    line-height: 1;
    letter-spacing: -2px;
}

.detail-header h2 {
    font-size: 2.5rem;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -1px;
}

.section-block {
    margin-bottom: 3rem;
}

.section-block h3 {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-tertiary);
    margin-bottom: 1rem;
    font-weight: 600;
}

.spec-text {
    font-size: 1.2rem;
    line-height: 1.7;
    color: var(--text-secondary);
}

.best-practices-box {
    background: rgba(255, 255, 255, 0.03);
    border-left: 4px solid var(--border-color);
    /* Updated dynamically */
    padding: 1.5rem;
    border-radius: 4px;
    font-size: 1.05rem;
    line-height: 1.6;
    color: var(--text-primary);
}

.best-practices-box p {
    margin-bottom: 0.75rem;
}

.best-practices-box p:last-child {
    margin-bottom: 0;
}

.best-practices-box strong {
    color: #fff;
}

/* Framework Tabs */
.framework-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1rem;
}

.tab-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    padding: 0.75rem 1.5rem;
    font-family: var(--font-ui);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
}

.tab-btn:hover {
    color: var(--text-primary);
}

.tab-btn.active {
    color: var(--text-primary);
    border-bottom-color: var(--text-primary);
    /* Dynamically colored in JS usually, or keep white */
}

.snippet-content {
    background: #000;
    border-radius: 8px;
    padding: 1.5rem;
    border: 1px solid var(--border-light);
}

.snippet-pane {
    display: none;
    margin: 0;
    font-family: var(--font-mono);
    font-size: 0.95rem;
    color: #e2e8f0;
    overflow-x: auto;
}

.snippet-pane.active {
    display: block;
}

/* Color Classes applied dynamically */
.code-1xx .detail-header h1 {
    color: var(--color-1xx);
}

.code-2xx .detail-header h1 {
    color: var(--color-2xx);
}

.code-3xx .detail-header h1 {
    color: var(--color-3xx);
}

.code-4xx .detail-header h1 {
    color: var(--color-4xx);
}

.code-5xx .detail-header h1 {
    color: var(--color-5xx);
}

.code-1xx .best-practices-box {
    border-left-color: var(--color-1xx);
}

.code-2xx .best-practices-box {
    border-left-color: var(--color-2xx);
}

.code-3xx .best-practices-box {
    border-left-color: var(--color-3xx);
}

.code-4xx .best-practices-box {
    border-left-color: var(--color-4xx);
}

.code-5xx .best-practices-box {
    border-left-color: var(--color-5xx);
}

.bg-1xx {
    background: var(--color-1xx-bg);
    color: var(--color-1xx);
}

.bg-2xx {
    background: var(--color-2xx-bg);
    color: var(--color-2xx);
}

.bg-3xx {
    background: var(--color-3xx-bg);
    color: var(--color-3xx);
}

.bg-4xx {
    background: var(--color-4xx-bg);
    color: var(--color-4xx);
}

.bg-5xx {
    background: var(--color-5xx-bg);
    color: var(--color-5xx);
}

@media (max-width: 768px) {
    .main-content {
        flex-direction: column;
    }

    .status-list-container {
        width: 100%;
        height: 40vh;
        border-right: none;
        border-bottom: 1px solid var(--border-color);
    }

    .detail-panel {
        height: 60vh;
        padding: 2rem;
    }

    .detail-header h1 {
        font-size: 3.5rem;
    }

    .detail-header h2 {
        font-size: 1.75rem;
    }
}