/* Matte Midnight Blue Theme */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;600&display=swap');

:root {
    --midnight: #0b0c0e;        /* deep neutral with cold undertone */
    --matte-blue: #161a20;      /* graphite with blue whisper */
    --soft-blue: #222831;       /* smoky blue-grey */
    --text: #e6ecf3;            /* icy light grey */
    --accent: #627b94;          /* cold steel accent */
    --hover: #2c3440;           /* slate blue hover */
}

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

body {
    background: var(--midnight);
    color: var(--text);
    height: 100vh;
    overflow: hidden;
}

/* Layout */
.dashboard-container {
    display: flex;
    height: 100vh;
}

/* 1️⃣ Expandable Tab */
.expandable-tab {
    background: var(--matte-blue);
    width: 240px;
    transition: width 0.35s ease;
    overflow: hidden;
    position: relative;
    box-shadow: 2px 0 6px rgba(0, 0, 0, 0.25);
    display: flex;
    flex-direction: column;
    align-items: stretch;
}


/* Add Button - hidden until hover */
#add-btn {
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 6px;
    width: 32px;
    height: 32px;
    font-size: 22px;
    cursor: pointer;
    transition: background 0.2s ease, opacity 0.3s ease;
    margin: 10px auto;
    display: block;
}

#add-btn:hover {
    background: #2563eb;
}

/* Tab Header */
.tab-header {
    text-align: center;
    padding-top: 15px;
}

/* Tab List */
#tab-list {
    list-style: none;
    margin-top: 10px;
    padding: 0 10px;
    transition: opacity 0.4s ease;
}


#tab-list li {
    background: var(--hover);
    border-radius: 6px;
    padding: 10px;
    margin: 8px 0;
    cursor: pointer;
    transition: background 0.2s ease;
}


/* 2️⃣ Sidebar */
.sidebar {
    background: var(--soft-blue);
    width: 220px;
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: start;
    box-shadow: 2px 0 6px rgba(0, 0, 0, 0.3);
}

.sidebar h2 {
    margin-bottom: 15px;
    font-weight: 600;
    color: var(--accent);
}

.sidebar ul {
    list-style: none;
}

.sidebar li {
    padding: 10px;
    margin-bottom: 8px;
    background: var(--matte-blue);
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.2s ease;
}

.sidebar li:hover {
    background: var(--hover);
}

/* 3️⃣ Main Field */
main {
    flex: 1;
    background: var(--midnight);
    padding: 40px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

main h1 {
    font-size: 2rem;
    margin-bottom: 10px;
}

main p {
    color: #cbd5e1;
    font-size: 1rem;
}

.tab-item a {
    color: var(--text);
    text-decoration: none;
}