/* ====== GLOBAL ====== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Arial', sans-serif;
}

body {
    background-color: #f0f2f5;
    color: #333;
    transition: background 0.3s, color 0.3s;
}

/* ====== HEADER ====== */
header {
    background: linear-gradient(90deg, #4a00e0, #8e2de2);
    color: #fff;
    padding: 20px 30px;
    text-align: center;
    font-size: 1.8em;
    font-weight: bold;
    letter-spacing: 1px;
}

/* ====== CONTAINER ====== */
.container {
    display: flex;
    min-height: 80vh;
}

/* ====== SIDEBAR ====== */
.sidebar {
    width: 220px;
    background-color: #2f2f2f;
    color: #fff;
    padding: 20px;
}

.sidebar h2 {
    margin-bottom: 20px;
    font-size: 1.4em;
    border-bottom: 2px solid #fff;
    padding-bottom: 5px;
}

.sidebar ul {
    list-style: none;
}

.sidebar ul li {
    margin-bottom: 10px;
}

.menu-btn {
    width: 100%;
    padding: 10px;
    border: none;
    background-color: #4a00e0;
    color: #fff;
    cursor: pointer;
    border-radius: 8px;
    font-size: 0.95em;
    transition: background 0.3s;
}

.menu-btn:hover {
    background-color: #8e2de2;
}

/* ====== MAIN CONTENT ====== */
.content {
    flex: 1;
    padding: 25px;
}

/* ====== SECTION ====== */
.exercise-section {
    display: none;
    margin-bottom: 30px;
}

.exercise-section h2 {
    margin-bottom: 20px;
    color: #4a00e0;
    font-size: 1.5em;
}

/* ====== PROFILE CARD ====== */
.profile-card {
    display: flex;
    align-items: center;
    background-color: #fff;
    padding: 15px;
    border-radius: 12px;
    box-shadow: 0 3px 8px rgba(0,0,0,0.2);
}

.profile-card img {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    object-fit: cover;
    margin-right: 20px;
}

.profile-info h3 {
    font-size: 1.3em;
    margin-bottom: 10px;
    text-transform: capitalize;
}

.profile-info p {
    margin-bottom: 5px;
}

/* ====== BUTTON ROW ====== */
.button-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.normal {
    padding: 10px 15px;
    background-color: #4a00e0;
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
}

.normal:hover {
    background-color: #8e2de2;
}

/* ====== TOOL BOX ====== */
.tool-box {
    background-color: #fff;
    padding: 15px;
    border-radius: 12px;
    box-shadow: 0 3px 8px rgba(0,0,0,0.2);
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.tool-box .tool-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.pro-btn {
    padding: 10px;
    border: none;
    background-color: #4a00e0;
    color: #fff;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
}

.pro-btn:hover {
    background-color: #8e2de2;
}

.danger-btn {
    padding: 10px;
    border: none;
    background-color: #e04a4a;
    color: #fff;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
}

.danger-btn:hover {
    background-color: #ff6b6b;
}

.tool-box input[type="text"],
.tool-box input[type="number"] {
    padding: 8px;
    border-radius: 6px;
    border: 1px solid #ccc;
}

/* ====== GRADE BOX ====== */
.grade-box {
    background-color: #fff;
    padding: 15px;
    border-radius: 12px;
    box-shadow: 0 3px 8px rgba(0,0,0,0.2);
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.grade-box input[type="number"] {
    padding: 8px;
    border-radius: 6px;
    border: 1px solid #ccc;
}

/* ====== FOOTER ====== */
footer {
    background-color: #2f2f2f;
    color: #fff;
    text-align: center;
    padding: 15px 0;
    font-size: 0.9em;
}

/* ====== DARK MODE ====== */
body.dark-mode {
    background-color: #121212;
    color: #fff;
}

body.dark-mode .sidebar {
    background-color: #1e1e1e;
}

body.dark-mode .exercise-section,
body.dark-mode .tool-box,
body.dark-mode .profile-card,
body.dark-mode .grade-box {
    background-color: #1e1e1e;
    color: #fff;
}

body.dark-mode input,
body.dark-mode button {
    color: #fff;
}

/* ====== RESPONSIVE ====== */
@media(max-width: 900px){
    .container {
        flex-direction: column;
    }
    .sidebar {
        width: 100%;
        display: flex;
        justify-content: space-around;
    }
    .sidebar ul {
        display: flex;
        gap: 10px;
    }
    .sidebar ul li {
        margin-bottom: 0;
    }
    .profile-card {
        flex-direction: column;
        align-items: center;
    }
    .profile-card img {
        margin-bottom: 10px;
    }
    .button-row {
        justify-content: center;
    }
}