:root {
    --primary-color: #4a90e2;
    --primary-hover-color: #357abd;
    --danger-color: #d0021b;
    --danger-hover-color: #a80015;
    --success-color: #4caf50;
    --light-gray-color: #f4f7f6;
    --border-color: #e0e0e0;
    --text-color: #333;
    --font-family: 'Sarabun', 'Arial', sans-serif;
    --box-shadow: 0 4px 8px rgba(0, 0, 0, 0.08);
}
@import url('https://fonts.googleapis.com/css2?family=Sarabun:wght@400;500;700&display=swap');
body {
    font-family: var(--font-family);
    background-color: var(--light-gray-color);
    color: var(--text-color);
    margin: 0;
    line-height: 1.6;
}
.input-group { display: flex; gap: 1rem; align-items: center; }
.form-control {
    width: 100%; padding: 0.75rem; font-size: 1rem;
    border: 1px solid var(--border-color); border-radius: 6px;
}
.btn {
    padding: 0.75rem 1.5rem; font-size: 1rem; border: none;
    border-radius: 6px; cursor: pointer; text-decoration: none;
    text-align: center; transition: background-color 0.2s; white-space: nowrap;
}
.btn-primary { background-color: var(--primary-color); color: #fff; }
.btn-primary:hover { background-color: var(--primary-hover-color); }
.btn-danger { background-color: var(--danger-color); color: #fff; }
.btn-danger:hover { background-color: var(--danger-hover-color); }
.btn-secondary { background-color: #6c757d; color: #fff; }
.btn-secondary:hover { background-color: #5a6268; }

.project-table { width: 100%; border-collapse: collapse; }
.project-table th, .project-table td { padding: 1rem; text-align: left; border-bottom: 1px solid var(--border-color); }
.project-table th { background-color: var(--light-gray-color); }

/* **FIX**: ทำให้ปุ่มในตารางสวยงามและขนาดเท่ากัน */
.action-buttons {
    display: flex;
    gap: 0.5rem;
    justify-content: flex-end;
    align-items: stretch;
}
.action-buttons .delete-form { display: flex; }
.action-buttons .btn, .action-buttons a.btn { flex-grow: 1; height: 100%; }

.form-section, .project-list-section {
    background: #fff; padding: 1.5rem; border-radius: 8px;
    box-shadow: var(--box-shadow); margin-bottom: 2rem;
}