/* Reset */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: Arial, sans-serif; background: #f5f5f5; }

/* Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #fff;
    padding: 10px;
    border-bottom: 2px solid #ccc;
    position: fixed;
    top: 0; left: 0; right: 0;
    height: 140px;
    z-index: 1000;
}
header .puzzle { height: 100px; }
.header-center { text-align: center; }

/* Buttons im Header */
.header-left button, .header-right button {
    background: teal;
    color: white;
    border: none;
    padding: 10px;
    margin: 3px;
    cursor: pointer;
    border-radius: 5px;
    font-size: 14px;
}
.header-left, .header-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

/* Layout Container */
.container {
    display: flex;
    margin-top: 140px;
}

/* Sidebar links */
.sidebar-left {
    width: 200px;
    background: #d6f5f5;
    padding: 10px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.sidebar-left button {
    background: teal;
    color: white;
    border: none;
    padding: 12px;
    cursor: pointer;
    border-radius: 5px;
    font-size: 14px;
    width: 100%;
}
.sidebar-left button:hover { background: #008080; }

/* Content */
main#content {
    flex: 1;
    background: #eee;
    min-height: calc(100vh - 140px);
}
iframe#contentFrame {
    width: 100%;
    height: 100%;
    border: none;
}