.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgb(248, 249, 255);
    border-radius: 0px 0px 15px 15px;
    padding: 0;
    margin-bottom: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    width: 100%;
    box-sizing: border-box;
    z-index: 3000;
}
.header-content {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    box-sizing: border-box;
    padding: 30px 36px 30px 36px;
    position: relative;
}

/* 반응형: 모바일에서 nav-tabs 숨기고 햄버거 노출 */
@media (max-width: 900px) {
    .header-content .nav-tabs {
        display: none !important;
    }
    .hamburger-btn {
        display: flex;
    }
    .container {
        padding: 200px 10px 10px 10px;
    }
}
@media (min-width: 901px) {
    .nav-overlay {
        display: none !important;
    }
    .hamburger-btn {
        display: none !important;
    }
}

.header-content h1 {
    font-size: 2em;
    font-weight: 800;
    color: #764ba2;
    margin-bottom: 8px;
    margin-top: 8px;
    text-align: center;
}
.header p {
    color: #4a5568;
    font-size: 1.1em;
    margin-bottom: 18px;
    text-align: center;
}
.header .nav-tabs {
    margin-bottom: 0;
    margin-top: 18px;
    /* width: 100%; */
    display: flex;
    justify-content: center;
    gap: 12px;
    background: none;
    box-shadow: none;
}

.back-btn {
    position: absolute;
    top: 10px;
    left: 15px;
    z-index: 10;
    font-size: 1.08em;
    color: #764ba2;
    font-weight: 600;
    background: none;
    border: none;
    outline: none;
    padding: 6px 18px 6px 18px;
    min-width: 90px;
    min-height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 7px;
    cursor: pointer;
    transition: transform 0.15s, box-shadow 0.18s, background 0.18s;
    box-shadow: none;
    border-radius: 50px;
    text-decoration: none;
    line-height: 1.2;
}

.back-btn:hover {
    transform: scale(1.08);
    background: #eeeeee;
    text-decoration: none;
}

@media (max-width: 768px) {
    .back-btn {
        top: 10px;
        left: 20px;
        min-width: 90px;
        min-height: 36px;
        font-size: 1em;
        padding: 4px 10px 4px 10px;
    }

    .container {
        padding: 200px 10px 10px 10px;
    }
    .header h1 {
        font-size: 2em;
    }
    .comparison-grid {
        grid-template-columns: 1fr;
    }
    .nav-tabs {
        flex-direction: column;
    }
    .nav-tab {
        min-width: auto;
    }
    .generator-controls {
        grid-template-columns: 1fr;
    }
    .memo-list {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .header-content {
      padding: 25px 20px 12px 20px;
    }
    .header-content p {
      margin-bottom: 2px;
    }
    .back-btn {
      top: 8px;
      font-size: 1em;
      padding: 4px 10px;
      min-width: 60px;
      min-height: 28px;
    }
  }