/* ============================================
   Text Case Converter Styles
   Clean, split-pane developer aesthetic
============================================ */
:root {
    --bg: #0f0f1a;
    --surface: rgba(255, 255, 255, 0.04);
    --border: rgba(255, 255, 255, 0.08);
    --text: #f1f5f9;
    --text-muted: #64748b;
    --accent: #a855f7;
    --accent-glow: rgba(168, 85, 247, 0.3);
    --radius: 12px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Outfit', sans-serif;
}

body {
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    background-image:
        radial-gradient(ellipse at 20% 10%, rgba(168, 85, 247, 0.1) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 90%, rgba(99, 102, 241, 0.07) 0%, transparent 50%);
}

.tool-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 2rem;
    border-bottom: 1px solid var(--border);
}

.back-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

.back-link:hover {
    color: var(--text);
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 700;
    color: var(--accent);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 2rem;
}

.tool-header {
    text-align: center;
    margin-bottom: 2.5rem;
}

.header-badge {
    display: inline-block;
    padding: 0.35rem 1rem;
    background: rgba(168, 85, 247, 0.12);
    color: var(--accent);
    border: 1px solid rgba(168, 85, 247, 0.25);
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    margin-bottom: 1rem;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    background: linear-gradient(135deg, #f1f5f9, var(--accent));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.tool-header p {
    color: var(--text-muted);
    font-size: 1rem;
    max-width: 520px;
    margin: 0 auto;
    line-height: 1.65;
}

/* Case Grid */
.case-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 0.75rem;
    margin-bottom: 2rem;
}

.case-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.4rem;
    padding: 1rem 0.5rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.2s;
    color: var(--text-muted);
}

.case-btn:hover {
    border-color: rgba(168, 85, 247, 0.4);
    color: var(--text);
}

.case-btn.active {
    border-color: var(--accent);
    color: var(--accent);
    background: rgba(168, 85, 247, 0.08);
    box-shadow: 0 0 20px rgba(168, 85, 247, 0.15);
}

.case-example {
    font-family: 'Fira Code', monospace;
    font-size: 1.2rem;
    font-weight: 700;
    line-height: 1;
    color: inherit;
}

.case-name {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    text-align: center;
}

/* Editor Layout */
.editor-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
}

.pane {
    display: flex;
    flex-direction: column;
}

.pane-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.active-label {
    color: var(--accent);
}

.sm-btn {
    background: var(--surface);
    border: 1px solid var(--border);
    color: var(--text-muted);
    border-radius: 7px;
    padding: 0.35rem 0.75rem;
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.3rem;
    transition: all 0.2s;
}

.sm-btn:hover {
    color: var(--text);
    border-color: rgba(255, 255, 255, 0.15);
}

.pane textarea {
    flex: 1;
    min-height: 400px;
    resize: none;
    background: rgba(0, 0, 0, 0.25);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text);
    padding: 1.25rem;
    font-size: 1rem;
    line-height: 1.7;
    font-family: 'Outfit', sans-serif;
    transition: border-color 0.2s;
}

.pane textarea:focus {
    outline: none;
    border-color: var(--accent);
}

.pane textarea::placeholder {
    color: var(--text-muted);
    opacity: 0.5;
}

.pane textarea[readonly] {
    opacity: 0.85;
    cursor: default;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: #10b981;
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    box-shadow: 0 10px 15px rgba(16, 185, 129, 0.3);
    transform: translateY(150%);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 9999;
}

.toast.show {
    transform: translateY(0);
}

@media (max-width:800px) {
    .case-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .editor-layout {
        grid-template-columns: 1fr;
    }

    h1 {
        font-size: 2rem;
    }
}