:root {
    --primary: #2563eb;
    --primary-dark: #1e40af;
    --bg-color: #f8fafc;
    --surface: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --unread: #22c55e;
    --danger: #ef4444;
    --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
}

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

body {
    font-family: var(--font-sans);
    background: var(--bg-color);
    color: var(--text-main);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.app-container {
    max-width: 600px;
    margin: 0 auto;
    min-height: 100vh;
    background: var(--surface);
    box-shadow: 0 0 20px rgba(0,0,0,0.05);
    display: flex;
    flex-direction: column;
}

/* Header / Search Bar */
.top-bar {
    padding: 1rem;
    background: var(--surface);
    position: sticky;
    top: 0;
    z-index: 10;
    border-bottom: 1px solid var(--border);
}

.search-box-container {
    display: flex;
    gap: 0.5rem;
}

.search-input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border);
    border-radius: 12px;
    font-size: 1rem;
    background: var(--bg-color);
    transition: all 0.2s;
}

.search-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}

.btn {
    padding: 0 1.25rem;
    border: none;
    border-radius: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: opacity 0.2s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.btn:active { opacity: 0.8; }

.btn-primary { background: var(--primary); color: white; }
.btn-icon { padding: 0.75rem; background: var(--bg-color); color: var(--text-main); }
.btn-scan { background: var(--text-main); color: white; }

/* Board List */
.board-list {
    padding: 0.5rem;
}

.board-card {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    margin-bottom: 0.5rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    cursor: pointer;
    transition: transform 0.1s;
}

.board-card:active { transform: scale(0.98); }
.board-card.unread { border-left: 4px solid var(--unread); }

.board-info h3 { font-size: 1.1rem; font-weight: 600; }
.board-meta { font-size: 0.85rem; color: var(--text-muted); margin-top: 0.2rem; }

/* Board View */
.board-view {
    display: flex;
    flex-direction: column;
    height: 100vh;
}

.board-header {
    padding: 1.5rem 1rem;
    border-bottom: 1px solid var(--border);
}

.board-title { font-size: 1.5rem; font-weight: 800; letter-spacing: -0.02em; }

.board-content {
    flex: 1;
    padding: 1.5rem 1rem;
    overflow-y: auto;
    font-size: 1.1rem;
    white-space: pre-wrap;
    color: var(--text-main);
}

.board-footer {
    padding: 1rem;
    border-top: 1px solid var(--border);
    font-size: 0.8rem;
    color: var(--text-muted);
    text-align: center;
    background: var(--bg-color);
}

/* Utilities */
.hidden { display: none !important; }
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background: #333;
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 99px;
    font-size: 0.9rem;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    z-index: 100;
}